King Tides: How this event has risen into our vocabulary
Brian Caufield, CDM Smith
Those living in the coastal floodplain are hearing about ‘King Tides’ in the media and local agencies are looking to crowd source flooding information during these events. While a King Tide, or perigean spring tide, is an especially high tide, it is not that unusual in that we can predict its occurrence and elevation. This presentation will look at tidal observations at the NOAA Tide Gage in Boston Harbor and looking at the past occurrences of King tide and evaluate how much the tide has changed in height through time. This presentation looks to answer the question about is flooding getting worse with each occurrence of a King tide.
Presenter Bio: Mr. Caufield is a Senior Coastal Engineer with CDM Smith. He has over 20 years of experience in coastal and coastal floodplain issues.
Assessing Coastal Flooding Vulnerability Case Study: City of Delray Beach Intracoastal Waterway
Douglas Mann, Aptim Environmental & Infrastructure LLC
Co Authors: Tara Brenner, Jeff Needle
In recent years, several coastal Florida communities have been experiencing more frequent and increased flooding within streets, parks, and other facilities that border the Intracoastal Waterway (ICW). In the City of Delray Beach, in southeast Florida, coastal flooding is primarily due to seasonal high tide events, commonly referred to as King Tides, but is also affected by storm surges in the Atlantic Ocean. After nuisance flooding events in 2017, the City sought to assess its vulnerability to future seasonal flooding and to identify potential options to protect its infrastructure and citizen’s property. This abstract is submitted to provide a case study for how vulnerability to coastal flooding was assessed in Delray Beach with the 2018 Intracoastal Waterway Water Level & Infrastructure Vulnerability Study, and the next steps to improving the City’s coastal resiliency.
In support of the City’s goals for this study, APTIM reviewed available water level data, analyzed return periods of extreme events, and considered sea level rise guidance to determine water level projections for the City’s requested 30-year and 75-year planning horizons. Based on the water level analyses performed, elevation standards were proposed for infrastructure improvements for the 30-year and 75-year planning horizons.
Field investigations were performed to catalogue existing conditions of seawalls, stormwater inlets and outlets, and backflow prevention devices along approximately 4 miles of the ICW and the adjoining canals within the City’s study area in early 2018. Analyses of the collected field data were performed to support the City in assessing its vulnerability to future seasonal flooding and to identify options to protect its infrastructure and citizen’s property.
It was determined that the City is primarily vulnerable to coastal flooding due to low or unmaintained seawalls, and low or unprotected stormwater inlets under both private and public ownership. Through analyses of current conditions and in consultation with City staff, the following recommendations for improving resilience to coastal flooding have been concluded from this study:
To guide implementation of seawall and stormwater system improvements by private residents, the City may develop ordinances to mandate elevations and timing of improvements to improve resiliency to coastal flooding City-wide. In pursuing a City guided implementation method, the City will weigh the benefits of implementing a time specific resiliency goal versus allowing for ongoing sea level rise and recurring storms to trigger improvements.
Presenter Bio: Mr. Mann is currently the Lead Coastal Engineer with Aptim Environmental & Infrastructure, LLC He holds a bachelors in civil engineering from the University of Delaware and a master of science degree in coastal engineering from the University of Florida.
Mr. Mann is a licensed engineer in five states and is recognized by ASCE as a diplomate in coastal engineering. His current interests include shoreline protection, inlet management, coastal structures, and mitigating the effects of sea level rise on our built infrastructure.
Taking That First Step: Flooding & Vulnerability Study for Carolina Beach, NC
Adam Priest, APTIM
Co Authors: Kenneth Willson
In recent years, the Town of Carolina Beach has experienced more frequent and increased flooding of the public and private infrastructure located along Canal Drive and Florida Avenue that borders the Carolina Beach Yacht Basin. Flooding is primarily due to seasonal high tide events (commonly referred to as King Tides), storm related high tides, and rainfall events. Faced with existing flooding challenges and recognizing the reality of rising sea levels, the Town commissioned a study to: 1) determine a recommended bulkhead elevation to mitigate overtopping over a 30-year time horizon; 2) evaluate the elevation and conditions of the bulkheads along Canal Drive and Florida Avenue; and 3) to implement a long-term monitoring program aimed at better understanding tidal fluctuations and rainfall totals driving flooding events.
Recommendations to mitigate flooding within the project area far exceed the Town’s capability to implement at one time. The study ended up producing a recommended multi-year system to implement flood mitigation strategies specifically intended to allow for an iterative implementation process and allow the Town to prioritize its resources in those areas that demonstrate the most effective flood risk reduction.
Through this presentation, we will provide an overview of the study approach and explain the novel implementation approach, which is geared toward a multi-year adaptive management cycle. This approach allows finite public resources to be spent on the most effective strategies in the highest priority areas and provides a metric by which implementation can be clearly measured and assessed.
Presenter Bio: Adam Priest is a coastal engineer for APTIM. Since 2000, he has managed and monitored civil and coastal engineering projects in North Carolina, Virginia, Florida, Louisiana, Texas, and the Caribbean. The projects have ranged from geotechnical design and construction inspection for civil infrastructure projects to shoreline stabilization projects that include beach nourishment, dune restoration, coastal structures, and dredging operations. Mr. Priest is also a licensed FAA Part 107 Drone Pilot with over 20 hours of flight time and 200+ flights. Mr. Priest currently resides in Carolina Beach, North Carolina.
Money Matters: Funding for Texas Coastal Restoration Projects
Jane Sarosdy, Sarosdy Consulting
Implementing projects to restore, protect, and enhance the many resources of the Texas coast has always been a financial challenge. Fortunately, an unprecedented influx of funding is becoming available for Texas coastal projects. Legislative actions by Congress and the Texas legislature and legal actions stemming from the Deepwater Horizon incident (DWH) will generate millions of dollars for coastal restoration over the coming years.
This presentation will summarize the key features of the following state and federal funding sources for Texas coastal restoration: (1) Texas Coastal Management Program (CMP) Grant Program; (2) Texas Coastal Erosion Planning & Response Act (CEPRA) Grant Program; (3) Gulf of Mexico Energy Security Act of 2006 (GOMESA) funding for Texas; (4) Deepwater Horizon (DWH) National Fish & Wildlife (NFWF) Gulf Environmental Benefit Fund; (5) DWH Natural Resource Damage Assessment (NRDA) Trustee Council and Trustee Implementation Group (TIG) Restoration Plans; and (6) RESTORE Act grant programs.
The Texas CMP was authorized in 1997. It passes through most of the federal funds it receives as a participant in the National Coastal Zone Management Program as subgrants. The Texas CMP grant program is administered by the Texas General Land Office (GLO), a state agency with broad authority over a number of coastal matters. The Texas CMP grant program provides funding on an annual basis for activities authorized by the Coastal Zone Management Act.
The need to respond to coastal degradation caused by tropical weather systems, relative sea level rise, and the effects of development and navigation has prompted federal and state legislative action to support restoration efforts.
The Texas legislature established the CEPRA program in the Texas General Land Office (GLO) to address alarming rates of coastal erosion. The CEPRA program provides biennial grant funding for a variety of erosion response projects.
Congress passed GOMESA to address coastal damage caused by activities related to offshore energy development. The GOMESA program allocates to the four Gulf states that permit offshore energy development and their coastal counties an annual portion of Outer Continental Shelf (OCS) revenues for coastal restoration. Texas received over $40 million in GOMESA funds for FY 2017, and may receive up to $90 million annually. The GLO administers the Texas GOMESA funding, and it has indicated that the funds will be used to implement top tier projects in the GLO’s 2019 Coastal Resiliency Master Plan.
The settlement of criminal charges and civil legal claims arising from DWH resulted in several large restoration funding allocations to Texas. The NFWF GEBF awards restoration grants from the criminal penalties from the DWH case. Texas also receives DWH allocations to compensate for natural resource injuries through the NRDA Trustee Council and the Texas TIG. Finally, Texas receives restoration funding through the RESTORE Act, which allocates billions to the Gulf states from the DWH civil penalties. Each of these funding sources provides millions in coastal restoration funding in Texas.
Presenter Bio: Jane Sarosdy is the president of Sarosdy Consulting. She previously served as director of the Coastal Law Team, then as director of the NRDA Trustee Program, at the Texas General Land Office. She participated in the early restoration efforts of the Deepwater Horizon NRDA Trustee Council and worked with state officials to set up RESTORE Act processes in Texas. She works with clients on a variety of coastal matters including obtaining grant funding, working with government agencies, and developing planning and policy initiatives. Jane received a B.A. in English from Tulane University and a J.D. from Stanford Law School.
Wetland restoration along the Southern California coast – meeting the challenges of future?
Cindy Kinkade, AECOM
Co Authors: Dick Rol, Aaron Andrews
Coastal wetlands in Southern California represent highly valuable and limited resources. In the context of climate change and sea level rise, coastal wetland restoration projects must meet short term habitat goals while providing long-term benefits and consider unique climate change challenges at each site. This presentation will focus on lessons learned for coastal wetland restoration/enhancements efforts in 3 locations: San Elijo Lagoon, San Dieguito Lagoon, and South San Diego Bay. We will describe the purpose of each project and design solutions to address future climate change scenarios. One is currently in the planning phase, one is underway, and one has been implemented.
San Elijo Lagoon: The San Elijo Lagoon Restoration Project is currently under construction, and sand placed at Cardiff State Beach as part of material disposal was awarded the “Best Restored Beach” by ASBPA in 2018. Restoration within the lagoon focuses on improving water quality by removal of high-nutrient sediments, and increasing the ability to drain storm flows entering the lagoon, particularly given the potential increase in severity/frequency of storm events due to climate change. Sea level rise is also addressed by inclusion of transitional habitat for short-term refugia and long term wetland habitat. The lagoon extends inland and includes gradual rises in elevation to provide for wetland habitat transgression during sea level rise. Both the construction approach and inlet maintenance allow for placement of sand on area beaches, a more short-term, but critical, strategy for shoreline protection in the region’s urbanized coastline.
San Dieguito Lagoon W-19: This project has completed the 65% design phase and environmental review. In anticipation of sea level rise, a large transitional area has been incorporated into the project. Sediment delivery to the beach is another issue for downstream coastal cities. In California much of the river sediment delivery process is impeded by dams and historic quarries, and further reductions in delivery are a concern. A primary focus of design on this site is minimizing the reduction in sediment delivery to the coastline, minimizing impacts to beach width. Beach sand placement and inlet maintenance at the river are critical project components to help provide short-term protection from wave action along the coastline.
South Bay Wetland Restoration: This project has been constructed within the Sweetwater Marsh Unit of the San Diego Bay National Wildlife Refuge which supports several federally listed plant and wildlife species including California least tern (Sterna antillarum browni).
This project restored intertidal mudflat, salt marsh, and open water, and included considerations for sea level rise. In addition to wetland design components, the project balanced soil disposal needs through on-site placement of excavated material within an established California least tern colony. This solution raised the elevation of the known colony, protecting it from future sea level rise conditions. The surface of the nesting area was restored to suitable nesting conditions and during the nesting season following construction, more California least terns nested on the site than in previous years. The project is now 3 years post-construction and tern usage remains high.
Presenter Bio: Cindy Kinkade is a Senior Project Manager at AECOM and focuses on management of coastal restoration projects in the San Diego region. With over 20 years of professional experience in both the private and public sectors, she has a broad knowledge of environmental compliance requirements for projects, from planning and design review through construction and post-construction monitoring. Cindy received Masters in Environmental Management and Public Policy from Duke University in 1999. She coordinates environmental compliance for projects and has expertise in CEQA/NEPA document preparation; agency and permitting coordination; and mitigation implementation and reporting requirements.
Sea Turtle Conservation: A Changing Landscape
Kelly Thorvalson, South Carolina Aquarium
Co Authors: Kelly Thorvalson, Albert George, Susan Hill Smith
The South Carolina Aquarium uses its facilities to aid sick and injured sea turtles found along the eastern seaboard. These efforts in combination with additional sea turtle conservation strategies such as nest protection, in-water research, and fisheries regulations has helped sea turtle populations begin to show signs of recovery. However, persistent and pervasive plastic litter in the marine environment is increasingly responsible for unintended yet often fatal consequences for sea turtles and other wild species, and rising sea levels threaten sea turtle nesting grounds and all coastal inhabitants. These rapid environmental changes pose a significant threat to sea turtles across the globe and traditional conservation strategies alone may not be sufficient to save these threatened and endangered species.
In collaboration with ROK Technologies and MDI Biological Laboratory, the South Carolina Aquarium is working to proactively mitigate plastic pollution and understand rising seas by crowdsourcing meaningful, actionable data to conserve sea turtles and other marine life, ultimately improving the health and safety of our shared physical environment. Learn how citizen science aided by app technology has helped coastal South Carolina communities craft solutions including reducing single-use plastics in businesses and creating laws restricting point-of-sale plastic packaging. Litter data has helped defend plastic reduction ordinances as the issue spilled over to the state Legislature. Partners include the grassroots group Isle of Palms Cleanup Crew which looked to the Aquarium’s conservation team for guidance in documenting 23,000-plus pieces of beach trash collected over the summer 2018.
Presenter Bio: Kelly Thorvalson received a Bachelor of Science degree in Marine Biology from the College of Charleston and began working with the South Carolina Aquarium in 1999, a year before the Aquarium opened its doors. In addition to helping build the initial animal collection and caring for offshore reef exhibits, Kelly helped with the first sea turtles admitted for rehabilitation just after opening. For 12 years, Kelly managed the Sea Turtle Care Center, greatly developing the program including a major expansion that opened in 2017. In Kelly’s current position as Conservation Programs Manager, she is helping to advance sea turtle conservation initiatives in relation to plastic pollution, sea level rise, climate change and sustainable seafood.
Habitat Mapping and Modeling for the Management of Wildlife, Land, and Infrastructure on a Barrier Island
Liliana Velasquez-Montoya, US Naval Academy
Co Authors: Elizabeth J. Sciaudone, Ayse Karanci, Rebecca Harrison
Barrier islands are evolving coastal environments driven by natural and anthropogenic processes. Management of these dynamic regions requires long-term monitoring that allows identifying evolutional trends of habitat, morphology, and physical conditions that could potentially affect wildlife and infrastructure. Such a monitoring program has been implemented at the Pea Island National Wildlife Refuge (PINWR) with 23.6 km2 of land and 104 km2 of Proclamation Boundary waters that hosts birds, mammals, reptiles, and amphibians, including endangered species. As a part of the careful balance between maintaining a transportation corridor along the barrier island and continuing to support the PINWR aims to protect and conserve migratory birds and other wildlife resources, the North Carolina Department of Transportation (NC DOT) funds a multi-purpose Coastal Monitoring Program. This program, ongoing since 2011, provides critical information to the NC DOT as it makes decisions about future transportation planning and works closely with the U.S. Fish and Wildlife Service on habitat monitoring.
The aim of this study is to identify and model habitat changes from 2012 until present at PINWR, based on annual high-resolution (0.5 ft) Color Infrared (CIR) imagery and orthophotography collected under auspices of the Coastal Monitoring Program. Initial phases of the analysis were devoted to identifying habitat classes that could help answers relevant management issues in the Refuge. Testing and validation of supervised classification methods in GIS led to a final set of 13 habitat classes that can be accurately classified from the CIR imagery. Annual habitat maps are a combination of semi-automated classification methods. Results indicate that marshes are the predominant habitat in the island, followed by managed wetlands. General trends indicate that marshes tend to prevail over shrubs and salt flats. Effects of storms and recovery periods are also captured through the semi-automated classification of bare sand, maritime brush, vegetated and unvegetated dunes, and beaches. Color-coded matrices and spatial visualizations of habitat changes are currently being used to inform management decisions and transportation planning within the refuge. Future work will focus on modeling and predicting habitat evolution using historical trends via environmental modeling tools and geospatial techniques.
Presenter Bio: Liliana holds a Ph.D. in Civil Engineering and a M.Sc. in Earth Sciences with focus on oceanography. She is currently an assistant professor at the US Naval Academy. Her research interests include tidal inlet morphodynamics, GIS-based spatial and temporal analysis applied to assess morphological evolution of coastal landforms, numerical modeling of sediment transport, estuarine dynamics and coastal morphology.
Riverbank Stabilization Design to Protect Critical Infrastructure along a Tidal River in Northeast Massachusetts
Brandon Raymond, Geosyntec Consultants
Co Authors: Dan Bourdeau, Paul Tschirky, Marisa Zelmer
The Merrimack Valley Regional Transit Authority (MVRTA) maintains an Operating Facility in Haverhill, Massachusetts along the tidal portion of the Merrimack River. Since 2016, significant bank erosion has been taking place over an approximately 500-linear-foot stretch of shoreline along the northwest corner of the MVRTA Operating Facility parking garage. The bank erosion has been observed to have caused damage to an MVRTA-owned stormwater outfall, and potentially to the parking garage, itself.
Geosyntec has been retained by MVRTA to design, permit, and supervise the construction of a riverbank stabilization project. The project must mitigate future erosion, protect MVRTA property from damage, and include a re-design and re-construction of the MVRTA outfall. The final remedy for the bank stabilization project is expected to be a combination of compacted structural fill, armored stone revetment, and vegetative stabilization practices. The presentation will examine the benefits and design process of integrating nature-based solutions with traditional erosion protection strategies.
The primary challenge to design and construction of the final remedy will be proximity to Essential Fish Habitat. The Site is directly adjacent to critical spawning habitat of the shortnose sturgeon. Pre-application coordination with Massachusetts Division of Fisheries and Wildlife (MassDFW) and the Natural History and Endangered Species Program (NHESP) is currently underway.
Presenter Bio: Brandon Raymond is a Coastal Engineer based in Massachusetts with over eight years of experience focused on modeling, designing, and constructing coastal engineering and sediment remediation projects.
His experience includes the analysis and numerical modeling of coastal processes, including wave transformation, beach morphology and nearshore circulation; design for both hard and soft shore protection projects; and modeling of hydrodynamics, waves, and sediment transport in rivers, lakes, open coasts, and estuarine systems.
Post-Storm Beach-Dune Recovery on a Meso-Tidal Barrier Island
Jean Ellis, University of South Carolina
Co Authors: Mayra Roman-Rivera, Michelle Harris, Peter Tereszkiewicz
The short-term impact of storms along barrier islands have been intensively studied. However, understanding the meso-scale post-storm recovery is more challenging because it requires a longitudinal data set and/or pre-storm data collection to quantify the necessary energetics and/or forcing agents. This paper therefore investigates the recovery of a beach-dune system located in the Southeast United States, specifically the Isle of Palms, South Carolina. The Isle of Palms is a drumstick barrier island located 24 km NNE from Charleston. Two sections of the island are considered for this analysis: the ‘anthropogenic’ site that is adjacent to the largest public parking area on the island and susceptible to substantial beachgoer traffic, and the ‘control’ site that experiences scant human foot traffic and a wide beach. Two temporal durations are considered: 1) post-Hurricane Matthew (2016) to pre-Hurricane Irma (2017) and 2) post-Hurricane Irma to pre-Hurricane Florence (2018). We assume Hurricanes Irma and Florence were substantial enough storms that that force the beach-dune system to restart the recovery process. The morphological impact of the storms is compared using the Storm Impact Scale (Sallenger, 2000) and by comparing digital elevation models (DEMs). The DEMs were generated from in situ topographic surveys that occurred every 3-4 weeks. There was differential recovery of the anthropogenic and control beach-dune sites post-Hurricanes Matthew and Irma. The recovery was inhibited by mid-latitude cyclones impacting the region during the winter seasons. This research considered two year-long data sets. However, given that the South Carolina coast has been impacted by substantial tropical cyclones on an annual basis since 2015, investigating recovery within this temporal window is appropriate and supported. Results from this study that quantify the recovery of a natural beach-dune system post-hurricane will assist coastal managers with future vulnerability assessments regarding heavily trafficked coastlines and with policy enactment and changes regarding coastal conservation measures. This is especially important along the coast of South Carolina because it is common to create mechanical (scraped) dunes post-storms and this work may dissuade this action.
Presenter Bio: Dr. Jean Taylor Ellis is an Associate Professor of Geography at the University of South Carolina. She received her Ph.D. from Texas A&M University. She was a Fulbright Scholar, held a position at NASA’s Applied Science Program at Stennis Space Center, and was a NOAA Knauss Fellow. Dr. Ellis is the director of the WINDlab where she and her students investigate coastal and aeolian geomorphology and the impact of humans on the coastal environment. They also work with community members to bridge the gap between science and the publics.
Geomorphic Response of the Beach-Dune System to the 2017 and 2018 Hurricane Seasons at the Isle of Palms, SC
Co Authors: Jean Ellis, Mayra Roman-Rivera, Michelle Harris
Barrier islands are the coastlines first defense to tropical cyclones and can receive the brunt force of these storm systems. Wind, wave, and rainfall events play a significant role in the way that the barrier island system responds to storms. When major storms impact the same area more frequently, the ability for the system to respond and provide natural defense is potentially diminished. Isle of Palms (IOP) is a barrier island located approximately 24 km NNE of Charleston, South Carolina. According to the National Oceanic and Atmospheric Administration, this area has been affected by named storms every year since 2011, and each year since 2016 has been a major hurricane. Hurricane Irma was a major hurricane in 2017. It was a Category 5 on the Saffir-Simpson Scale at its most intense that weakened to a tropical storm by the time it reached IOP. Peak wind gusts were 55 miles per hour, and IOP received between six and seven inches of rainfall from September 10-12, 2017. During the 2018 season, Hurricane Florence was a major named storm that was a Category 4 at its most intense. This storm also weakened to a tropical storm before it reached the Isle of Palms. Maximum wind gusts were around 40 miles per hour, and IOP received approximately two inches of rain from September 14-17, 2018. Though neither of these storms made direct landfall at Isle of Palms, the island experienced impacts from both. This study compares digital elevation models (DEMs) from two sites at Isle of Palms before and after Hurricanes Irma and Florence. One site is located near Breach Inlet at 1st Avenue, where there is a scraped mechanical dune next to a natural dune system. The other is between 53rd and 54th Avenues, where there is a natural incipient foredune zone. We evaluate the volume loss, considering new spatio-temporal baselines from both of the storms. Cross-sectional beach-dune system data highlights the regions of erosion or accretion. Even though the storms impacted the Isle of Palms as tropical storms, they had drastically different characteristics, therefore the morphologic response was very different. This paper will discuss these variabilities in detail. Furthermore, these data provide a baseline that future studies of this area can consider when evaluating the potential damage of or planning for future hurricanes.
Presenter Bio: J. Brianna Ferguson is a M.S. student in the Department of Geography at the University of South Carolina. She is primarily interested in the surface roughness element of vegetation and its effects on the depositional patterns of aeolian sediment within incipient foredune zones. She is a member of the Wind-Induced Nearshore Dynamics Lab (WINDlab), where she also studies sea level rise and stormwater ponds. She completed her undergraduate degree in GIS and Geology at Texas A&M University where she also conducted research on coastal geomorphology at Padre Island National Seashore.
Application of Storm Erosion Index (SEI) to Hurricane Michael
Matthew Janssen, Stevens Institute of Technology
Co Authors: Laura Lemke, Jon Miller
Hurricane Michael made landfall as a Category 5 Hurricane on October 10, 2018 between Mexico Beach, Florida and Tyndall Air Force Base in Panama City, Florida. The storm caused damages totaling $25 billion (National Centers for Environmental Information, 2019). Hurricane Michael is unique in that it is the first Category 5 hurricane to make landfall since 1992 and only the fourth on record (National Oceanic and Atmospheric Administration, 2019). Additionally, the damage was concentrated in the immediate vicinity of Mexico Beach, with damages attenuating significantly to the west in Panama City Beach and east in Port Saint Joe (Kennedy et al., unpublished). The authors will assess the application of the Storm Erosion Index (SEI) developed by Miller and Livermont (2008) to explain the spatial variation in damages. SEI has been previously shown to accurately represent the impact of different coastal storms (Wehof et al., 2014, Herrington and Miller, 2010). The application herein, will demonstrate the ability of SEI to represent the spatial impacts within a single event.
Here, the WAVEWATCH III production hindcast (NOAA, 2019) and USGS water level measurements (2018) will be used quantify the SEI at intermediate locations throughout the Florida panhandle. At minimum, these locations will include Port Saint Joe, Cape San Blas, Mexico Beach, Tyndall AFB and Panama City Beach. The spatial variation in SEI will be compared to inventoried structural damages, erosion volumes and watermarks.
Presenter Bio: Matthew is a doctoral candidate at Stevens Institute of Technology working under the guidance of Jon K Miller, PhD. His primary research interests are in littoral processes and in the design and assessment of coastal protection projects. Prior to returning to graduate school, Matthew worked as professional engineer with a focus on the design, inspection and repair of coastal structures.
Coastal Plants in NC and their Response to Hurricane Florence
Steve Mercer, Coastal Transplants Inc
Vegetation along the coast is diverse in its species and unique in its composition. Dominant plant species occurring along the North Carolina coast include: Salt Meadow Hay, Sea Oats, Bitter Panicum, Sea Shore Elder, Sea Rocket, Beach Croaton, American Beach Grass, and Dollar Weed. Southeastern, Eastern, and the Outerbanks regions of North Carolina experience different vegetative compositions with American Beach Grass having a stronger presence in northern coastal areas.
Each region experienced different types of damage based on issues resulting from Hurricane Florence. The Southeastern region saw mainly issues of over wash with areas of total dune and vegetation loss closer to the boundary with the Eastern region. The Eastern region had dune and vegetation loss near the boundary with the Southeastern region which phased into water inundation. The Outerbanks had water inundation with scattered erosion, but no loss of dune or vegetation.
The presentation will focus on introducing the plant species dominant in NC; define regions and their specific issues post-Florence; and explore how the different vegetation fared in response to the storm conditions.
Presenter Bio: Steve Mercer, President, Coastal Transplants
Steve is President of Coastal Transplants, Inc. located in Bolivia, North Carolina. His many years of experience in growing and installing coastal vegetation has allowed him to expand his business along the Atlantic coast and in the state of Texas. The company currently grows and installs 500-700,000 warm season plants every year.
Regional sediment transport study in Poole and Christchurch Bays, UK
Jonathan Simm, HR Wallingford
Co Authors: Richard Lewis, James Sutherland, Michiel Knaapen
The beaches of Poole and Christchurch Bays in the south of England are important to their local communities for protection against erosion and flooding as well as the recreational space they provide. These beaches are extensively managed through beach nourishment or recycling, combined with construction and maintenance of groynes and seawalls. Three local councils are jointly considering the management of beaches between Swanage and Hurst Spit as a whole. They recognise the complexity of sediment transport within their shared area and the benefits in identifying how that resource could be managed holistically to optimise beach management. The councils have commissioned a detailed numerical model of sediment transport in Poole & Christchurch bays to facilitate a joined approach.
Previous studies of sediment transport and erosion along this frontage have tended to use one-line models of wave-driven beach plan-shape elevation (such as Beachplan or Genesis). These models allow the user to run a long time series of wave conditions from an established hindcast simulation. The use of a long time series allows seasonality and inter-annual variations in longshore transport and sediment budget to be determined. However these models only simulate wave-driven longshore transport along gently-curved beaches.
The bathymetry here is too complicated for such an approach to cover the entire region. Moreover, offshore sediment transport pathways and sinks are of interest as potential sources of sand for beach nourishment. Therefore the model developed is a fully-coupled coastal area model of wind, tide, waves and sediment transport, created using the open source, finite element TELEMAC modelling suite. It has a high resolution of 5m in the surf zone, expanding out to 5,000m outside the bays. The model has been set up using the latest data on bathymetry and seabed composition. It has been calibrated and validated against different periods of deployment of nine measurement frames, which recorded waves, currents and suspended sediment concentrations over periods of two months. A representative year and a 20-year simulation have been run and provide information on sediment pathways and transport rates. A morphological speed-up factor was used for the 20-year simulation.
This approach simulates many more processes than a one-line modelling approach and is much more computationally demanding. The model was run on 108 cores and took several weeks to run. A hugh amount of information is available from the model at each timestep, but shorter durations can be simulated than with a one-line model.
This presentation will discuss the model set-up and calibration, the simulations undertaken the and information from them (including contributions to a regional sediment budget). It will then discuss the advantages and disadvantages of such a modelling approach, compared to a one-line model.
Presenter Bio: Dr Jonathan Simm is Chief Technical Director for Resilience at UK-based research and consultancy organisation HR Wallingford. Jonathan leads research programmes in flood and coastal risk management. He was Technical Lead for the International Levee Handbook and is currently working on the International Guidelines for the use of Natural and Nature-Based Features. Jonathan chairs national and international committees and visits the US regularly. His passion is translating research and innovation into policy and practice.
Conditions Assessment and Asset Management Tool
Nina Reins, Freese and Nichols, Inc.
Co Authors: Juan Moya, Emily Shelton, Mathew Mahoney
The Texas Gulf Intracoastal Waterways (GIWW-T) main channel is a 379-mile-long, shallow-draft, man-made, protected waterway that connects 16 economically important ports along the Gulf of Mexico from the Sabine River to Brownsville, Texas. The U.S. Army Corps of Engineers (USACE) Galveston District has the responsibility of maintaining the GIWW-T to authorized depths and widths. From 1998 through 2012, an average of 6.2 million cubic yards was dredged annually from the GIWW-T (TTI, 2014) and either placed in authorized DMPAs or used beneficially. Most of this dredged material was placed in unconfined open water bay disposal sites and confined disposal facilities.
Since the construction of the GIWW-T in the early 1940s, the Dredge Material Placement Areas (DMPAs) along the GIWW-T have served a wide range of purposes including providing navigation efficiencies, shoreline stabilization for coastal communities, and support of diverse coastal habitats. However, after 60 years of dredging, some of the DMPAs have deteriorated to a point of instability, are submerged, out of capacity, or were never developed. The Texas Department of Transportation – Maritime Division (TxDOT-MD) selected Freese and Nichols, Inc., and Moffatt & Nichol, Inc. Joint Venture (FNI-MN-JV) to develop an inventory of the DMPA’s along the GIWW and an assessment logic to evaluate DMPAs based on various conditions criteria. The developed database and assessment criteria will serve as a new management tool for future coordination of beneficial use of dredged material. The assessment inventory also included obtaining ownership data, which was collected by Crouch Environmental Services, Inc. (CESI). Gathering ownership and available lease information was a key component of the data collection. Property ownership research included the collection of available data from each respective county’s Central Appraisal District (CAD); identifying the current property owner, parcel geometry; and lease information where available.
GIWW-T DMPAs can be categorized as upland (confined) disposal sites, which can be designated for containment dredged material, open water (unconfined) disposal sites, or partially confined sites. TxDOT-MD identified the need for a GIWW-T DMPA Conditions Assessment to be used as a DMPA asset management inventory tool. The developed methodology included an approach that comprised an analysis of DMPAs site conditions, ownership, available capacity evaluations, and infrastructure assessment. Another critical component for the assessment was the current capacity. Capacity calculations were based on an analysis of the current topography, which was determined through an analysis of the most recent LiDAR data and aerial photographs.
With the data collected, subsequent analysis, the team develop the described Asset Management Tool, which will help TxDOT-MD and USACE to maintain available information on the GIWW-T DMPAs. This presentation shows the details of the Asset Management Tool and how the data has been processed and scored to identify issues of concern or opportunities for DMPAs beneficial use of dredge material projects that are of priority to TxDOT and the USACE or their partners.
Texas A&M Transportation Institute (TTI). 2014. Texas Gulf Intracoastal Waterway Master Plan Technical Report.
Presenter Bio: Dr. Nina Reins is an engineer that works as the Technical Lead in the New Orleans office of Freese and Nichols. She has experience in the program and project management aspects of sediment management, coastal restoration and flooding mitigation infrastructure.
Using Regional Sediment Management (RSM) to Improve Galveston Island’s Beaches
Reuben Trevino, Galveston Park Board
Co Authors: Reuben Trevino
Galveston Island is a relatively flat, barrier island on the upper Texas coast, and is easily one of Texas’ most urbanized beach areas. Due to its proximity to the greater Houston metro area, the fourth (4th) largest population center in the nation approximately 50 miles to the north, Galveston’s beaches are under an ever increasing pressure to provide the desired beach experience to visitors. Located only 50 miles from the Texas / Louisiana state line Galveston is often referred to as the city “Where the Texas coast begins.” Galveston is the second most visited tourist destination in Texas (only behind the Alamo) and Galveston Island’s beaches are its biggest tourist attraction, drawing over 7,000,000 visitors annually. But, Galveston Island is a sediment deficit system with mostly erosional narrow beaches along the central and western portions of the Island experiencing erosion rates exceeding 8ft – 10ft per year in some areas, while locations at the eastern and western ends of the Island are rapidly accreting.
Residents of Galveston Island have sought to manage the eroding coastline and provide protection from an encroaching Gulf of Mexico through the development of a series manmade engineering marvels including: the paired North and South Jetties, Galveston Seawall, and the Seawall groin field. These activities sought to provide surge protection, and more specifically in the case of the Jetty’s and Groinfield, control the natural flow of sediment in the littoral system. Of the 7,000,000 annual visitors approximately 60% are “day trippers” whose intention it is to spend a day on the sand. Providing that on-demand beach user experience requires a long term and comprehensive plan that incorporates financing, endangered species “windows,” public procurement process, partnering/teaming opportunities, and real-world construction phase considerations. Beach nourishment/dune restoration projects are typically very large public infrastructure projects similar in scope to building a bridge or stormwater management system. If not managed correctly equipment and work zones can be spread over a wide area, potentially rendering sections of the beach unavailable during the critical summer tourism season.
This presentation will provide an overview of the Galveston Park Board’s approach to adaptively managing a dynamic sediment deficit coastal system, include a review of the Park Board’s recent research projects to update the “Galveston Island, Texas, Sand Management Strategies-2016” report, cooperatively developed by the Park Board and the U.S. Army Corp of Engineer (USACE), Engineer Research and Development Center (ERDC), in Vicksburg. This presentation will update recent efforts to fund research through grant applications and strategic partnerships, also included in the presentation will be a review of completed, current, and planned beach nourishment projects detailing planning considerations, implementation difficulties, potential unintended consequences and their relationship/impact to other beach and research projects. The presentation will give an in-depth look at the process followed by the Park Board to determine project and grant priorities and highlight other restoration projects apart from beach nourishment that also contribute to the health of the Island’s beaches.
Presenter Bio: Reuben has been an Eagle Scout since age 15, where his experiences led to his drive to preserve the Tx coast. Trevino has a MS Biology and is a certified TX Master & Coastal Naturalist. He has worked along the Tx Coast for over a decade managing their Coastal Resources at the Local Government level. In February 2016 he joined the Galveston Park Board of Trustees as the Director of Operations where he oversees numerous research and construction project related to improving RSM on the island while also overseeing the maintenance and upkeep of the Islands tourism assets.
Large Scale Coastal Restoration Concepts for the Texas Upper Coast Barrier Islands and the Present Availability of Sediment Sources: How Much Sediment is Needed?
Juan Moya, Freese and Nichols, Inc.
Co Authors: Juan Moya, Carla Kartman, Joshua Oyer
In November of 2015, the Texas General Land Office (GLO) and the U.S. Army Corps of Engineers (USACE) started a study on the actions that could be taken to ensure the Texas coast remains resilient for future generations. The main goal has been a study that: Protects lives, Property, jobs and the environment; Replenishes eroding sand dunes and beaches; Helps restore coastal wildlife habitats; And does so with minimal disruption of what makes the Galveston Bay area community so unique. The Project was called the Coastal Texas Protection and Restoration Feasibility Study, also known as the Coastal Texas Study. Under this study, USACE and GLO initiated an Environmental Impact Statement for the Texas Coastal Study. One of the main objectives of this study is to develop risk reduction (protection) measures to the Texas coastal barrier islands (TBIs) and the infrastructure, communities and habitats that live on them.
The TBIs are considered the first line of defense during storms and hurricanes protecting bays and Gulf shorelines and watersheds. Geomorphologically speaking, TBIs include barrier shorelines, islands, and headlands; inlets, beaches, dunes, wetlands and marshes among others. From the ecological point of view, these geomorphological features are the substrate of bird rookery islands, oyster reefs, marshes and seagrass beds. In conclusion: TBIs provide important, essential and critical substrate habitats for a wide variety of terrestrial and aquatic species on the Gulf and bays sides for marine and the fresher estuarine ecosystems.
In order to restore these TBIs and their geomorphic features, USACE and GLO need to identify at least 170,000,000 cubic yards of sediment to restore and develop sustainable alternatives to protect the TBIs. This presentation shows the steps GLO is taking to identify the geological units that have availability of sediment sources for coastal restoration on the areas recommended by the Texas Coastal Study. As the result of this effort, the Texas coastal geology is being reclassified with a non-traditional approach on the availability of sand by reclassifying the Beaumont Formation and the Holocene deposits on the coast for the sediments needed for coastal restoration. The results are being compared with the analysis of the TBIs considering their sustainability. Some key geomorphic features were compared to understand the trends of the TBIs and determine which specific features and sub-features have the potential for fast changes or potential disappearance though breaching or any other similar process. The comparison factors included: Age, geologic migration rates, shoreline migration rates, dune and ridge elevation, washover dynamics, geologic thickness, probability of rollback, navigation influence, engineering structural influence, magnitude of aeolian processes, availability of sediments for restoration, relative subsidence, flood potential and the probability of breaching. The main question is: how much sediment will be needed to sustain these features?
This presentation plays with different variables of physical conditions of the TBIs vs the sediments needed and the sediments available in the geological formations of the region. It finally presents several scenarios on the future steps that must be taken to complete these needed restoration projects.
Presenter Bio: Juan Moya is a Senior Geoscientist with Freese and Nichols. He works on the geological and geomorphological aspects of regional sediment management and coastal restoration in the Gulf of Mexico. For more than 35 years he has worked on coastal geomorphological issues in the Gulf of Mexico coast (in Mexico and the US) and the Caribbean.
Modeling fish distributions to inform offshore sand dredging impacts to Essential Fish Habitat
Bradley Pickens, CSS and Affiliate of NOAA National Centers for Coastal Ocean Science, Beaufort Laboratory
Co Authors: J. Christopher Taylor, Mark Finkbeiner, Deena Hansen
Multiple uses of the Outer Continental Shelf increase pressure on fish and their habitats. Sand dredging for beach nourishment and coastal restoration often targets shoals, which often function as ‘Essential Fish Habitat’ for federally managed species. In managing offshore sand dredging, the Bureau of Ocean Energy Management (BOEM) consults with the National Marine Fisheries Service regarding Essential Fish Habitat and potential dredging impacts. Yet, the spatial distribution and habitat relationships of fish are often unknown at the scales needed to assess the effects of management. Our objectives were to 1) identify shoal locations for the Atlantic and Gulf of Mexico, 2) model the distribution of fish based on habitat associations, and 3) streamline the assessment process by synthesizing biological and geological information into a geospatial tool. We first identified shoals using predictor variables of depth, heterogeneity of depth, slope, distance to shoreline, and the benthic position index. Then, we used fish monitoring data to model the distribution of variety of trophic levels and fish guilds, including shrimp, soft-bottom demersal fish, juvenile reef-associated fish, and shark species. We developed predictors of fish distribution aimed at untangling the role of geomorphology, wetlands/estuaries, prey species, and oceanographic conditions in shaping species’ distributions. Our results demonstrate that important habitat relationships and spatial patterns can be revealed by using a wide range of predictors that characterize multiple scales of marine ecosystems. Oceanographic conditions, such chlorophyll-a and temperature, often dictate the broad distribution of species, while variables such as sediment grain size and the benthic position index characterize a finer scale. Resulting maps further highlight patterns of fish distribution and associations with shoals. To support consultations, modeling data were integrated into a map-based tool, which includes information on past dredging events, shoals, known fish habitat associations, and a semi-automated report is the result. The geospatial tool will improve the consistency and accuracy of BOEM’s sand dredging assessments. As ocean uses continue to expand, a better understanding of spatial patterns, potential impacts, and improved communication, will be integral to successful marine resource management.
Presenter Bio: Brad Pickens is an applied ecologist and spatial modeler. He has expertise in predictive analyses, conservation planning, and using science to inform management applications.
Sorting of Offshore Sediment Sources by Hopper Dredging and Placement Operations
Jarrell Smith, US Army Engineer Research and Development Center
Co Authors: Doug Piatkowski, Leighann Brandt, Clay McCoy
Beach nourishment projects using dredged material must often meet sediment compatibility requirements including: sediment size, sediment sorting, mineral content, sediment color, and fine-sediment (< 63 µm) content. In most instances, the application of these regulations does not factor changes in these sediment characteristics from borrow areas to beach placement sites. Hopper dredging operations for beach and nearshore placement typically include periods of overflow, which is recognized to produce some degree of separation between the size fractions of the dredged sediment. The degree of separation and the controlling factors are the subject of this research. This work reviews prior research of sediment separation by hopper dredges, describes a field sampling campaign in which collected samples are used to define the fines content at the varying stages of the dredging process, and describes ongoing work to quantify the controlling factors of the observed sediment sorting.
The recent field study, conducted onboard the dredge Liberty Island at the Ship Island Restoration Project near Biloxi, Mississippi, found the fines content reduced sequentially from the borrow area, hopper, and beach. Hopper overflow removed 61% of the fine-sediment mass contained in the borrow area, and beach outwash removed 67% of the fines contained in the hopper. These two losses combined accounted for a removal of 87% of the fines dredged from the borrow area. Of the fine-sediment mass removed, 70% was removed by the overflow process and 30% was removed by beach outwash. These findings are consistent with other research (Coor and Ousley 2019) of change in fine-sediment content from more than 100 beach nourishment projects on the Florida coast.
The continuing study aims to extend the existing dataset to borrow areas with greater than 10% fine sediment content. The present study concludes that beach compatibility evaluations involving hopper overflow and pumpout should include quantitative accounting of changes in sediment properties between borrow area and beach. This study recommends several approaches for implementing the research findings in hopper dredging and beach nourishment planning and operations.
Presenter Bio: Dr. Jarrell Smith is a Research Civil Engineer with the Coastal & Hydraulics Lab of the Engineer Research & Development Center. He has been engaged in sediment transport and dredging-related research for more than 25 years. Much of the focus of his research involves the implications of small-scale physical transport phenomena on dredged material management. He earned a BS and MS in Civil Engineering in 1992 and 1994 from Clemson University and a PhD in Marine Science-Physical Oceanography from William and Mary in 2010.
MARINE MINERALS INFORMATION SYSTEM “A DATA MANAGEMENT PILLAR OF THE NATIONAL SAND INVENTORY”
Lora Turner, Bureau of Ocean Energy Management
Co Authors: Kerby Dobbs, Alexa Ramirez
Lora Turner1, Kerby Dobbs2, Alexa Ramirez3
1Bureau of Ocean Energy Management, Sterling, VA, USA
2Bureau of Ocean Energy Management, Sterling, VA, USA
3Quantum Spatial, St Petersburg, FL USA
Sediment resources, such as sand or gravel, located on the Outer Continental Shelf (OCS) are leased to local communities or Federal agencies to assist with restoration of shorelines or coastal wetlands. The Bureau of Ocean Energy Management’s (BOEM) Marine Minerals Program holds geospatial data obtained from our partners and aims to maximize the potential use of sediment resources. The Marine Minerals Information System (MMIS) is an ongoing initiative that BOEM started in 2014 with our State and Federal partners to better understand the scope of our National Sand Inventory and provide an information resource for our partners to use. BOEM’s approach is to manage marine minerals data as a national resource with the MMIS as one of the main tools to help us do this.
On a national scale, little is known about the character, quantity, and location of sediment resources on the OCS or the habitat this offers marine biological communities. To inform, support and enable multi-use ocean planning, coastal protection and restoration projects, it is crucial to know the location and extent of compatible sediment resources on the OCS. As a steward of offshore sediment resources, it is critical that we have our sand resources organized and that we allow easy access to this information. Making this data available through the MMIS is a step forward for coastal resilience and disaster relief planning. It is being enabled by closely collaborating with local municipalities, State and Federal agencies, and other stakeholders to understand, and assess our offshore sand resource: MMIS allows analysis and greater understanding of the National Sand Inventory.
The Marine Minerals Information System (MMIS) has an interactive viewer that contains information on past leases; environmental studies, cooperative agreements, as well as existing and potential sediment resources. MMIS is primarily compiled from derived information and is combined into a uniform data model to support the National Sand Inventory. The MMIS investment now holds more than 30 years of BOEM-funded geological and geophysical research data, data from more than 40 partners in federal, state and local government, academia and other entities. It includes offshore 18 coastal State’s, links to environmental studies and data from State cooperative agreements. The MMIS viewer allows the public to interactively access the data and information relevant to the offshore mineral resources throughout the U.S. Atlantic, Gulf and Pacific OCS. The viewer also utilizes publicly available web services (discovery via MarineCadastre.gov Web-based Tools) that are critical to identifying multi-use conflicts.
Presenter Bio: Lora Turner is a physical oceanographer within the Bureau of Ocean Energy Management’s Marine Minerals Program. Lora has over 26 years of experience in maritime operations serving in a variety of roles in the U.S. Navy serving as a naval oceanographer and meteorologist. Lora earned a master’s degree in Meteorology and Oceanography from the U.S. Naval Postgraduate School and holds a Bachelor’s degree in Physical Geography from University of Arizona. Currently, the focus of her work is leading and developing the Marine Minerals Program data holdings into a geospatial database: the Marine Minerals Information System (MMIS).
Coordination with Undersea Cable Owners
Robert Wargo, North American Submarine Cable Association
Co Authors: Susannah Larson, Kent Bressie
The presentation will provide recommendations for coordination with undersea cables, including contact information, recommended steps, and industry recommendations for separation between undersea cables and conflicting uses of the seabed.
Presenter Bio: Bob Wargo is the President of the North American Submarine Cable Association and an Executive Board member of the International Cable Protection Committee. He has 28 year of experience in the undersea cable industry.
Shoveling Sand Against the Tide?
Anders Bjarngard, GZA GeoEnvironmental, Inc.
The presentation will focus on observed and modeled shoreline change as compared to historical storm data and engineered modifications to the shoreline in the vicinity of the North Point of Plum Island in Newburyport, Massachusetts approximately 40 miles north of Boston. In the past 5 years, erosion rates approaching 100 feet per year have resulted in the current shoreline landing on the doorstep of homes and infrastructure. Two recent emergency dune nourishment projects have been successful in protecting the homes and infrastructure to date.
Numerical modeling including ADCIRC hydrodynamic/tidal current, SWAN wave modeling and XBeach erosion models were compared to historical observations as well as large scale physical model tests performed by USACE in the 1970’s. The results were used to help understand the dynamics of this complex river outlet with open exposure to the Atlantic Ocean and to develop the short-term dune nourishment projects as well as evaluate long term mitigating measures.
Permitting challenges, funding limitations and how the collaboration between municipal, state and federal government agencies with regulators and the community have been successful in preventing loss of homes to date. The construction of the dune nourishment projects and their performance will be reviewed. Current long-term considerations including large scale on-beach, and nearshore, nourishment with beneficial use of dredged material from local USACE projects will also be presented.
Presenter Bio: Anders Bjarngard is a licensed Professional Engineer and a Principal/Office Manager for GZA GeoEnvironmental’s coastal office in Amesbury, Massachusetts. He holds a BSCE from the University of Massachusetts Amherst and an MSCE from Tufts University. He is a geotechnical engineer with over 30 years of experience including: marine and coastal engineering; dam and flood control engineering; subsurface and bathymetric investigation; foundations, lateral earth support, bulkheads, revetments, sea walls and living shorelines; dune and beach nourishment, dredging; construction; slope stability, seepage, and settlement analyses; and preparation of associated permits, plans, specifications, and contract documents.
A SHORELINE MORPHOLOGY MODEL USING REPRESENTATIVE WAVES METHOD FOR SHORELINE STABILIZATION
Michael Kabiling, Taylor Engineering, Inc.
Co Authors: Michael E. Trudnak, Richard Bouchard
The Fort Pierce Shore Protection Project nourishes a 1.3-mi Atlantic Ocean shoreline south of Fort Pierce Inlet in St. Lucie County, Florida. The beach fill erodes nonuniformly with a hotspot along the northernmost 0.4 mi requiring nourishment after about two years of normal wave regime. This study validated a shoreline morphology model to evaluate designs and combinations of coastal structures to stabilize shoreline and increase the nourishment interval.
REPRESENTATIVE WAVES METHOD
Hydrodynamic and spectral wave models quasi-stationary time formulations allowed faster computation of long-term model validation. A littoral process model generated the equivalent effective waves to represent long-term wave climate and water levels at the offshore boundary. The littoral process model results show good agreement in the calculated cross-shore variations of the longshore transports for the full time series of waves and the selected representative waves for the one-year calibration period. The good agreement indicates the selected representative waves produce comparable net longshore transport as the full time series of waves and therefore can substitute for the full time series of waves to shorten the model computation time.
Comparison of the shoreline morphology model calculated and measured onshore (negative) and offshore (positive) shoreline net movement one year after beach nourishment provided good estimates of the erosion (shoreline recession) at monuments R-35, T-36, T-37, R-38, and T-40 where model results are within 22 ft of measurements. The shoreline morphology model overestimated erosion at monument R-34 and provided small accretion instead of erosion at monuments R-39 and T-41. The model results are generally consistent with the observed erosion pattern from monuments R-34 to R-38. Best agreement with measurement is from monuments R-35 to R-38—the specific area where the model was used to evaluate beach stabilization.
RESULTS OF ANALYSIS AND CONCLUSIONS
Simulations of long-term normal tides, waves, and storm conditions show (a) a shoreline movement pattern similar to the general historical pattern observed in the project area, including accurately indicating the largest erosion rate and shoreline retreat along the first 0.4 mi south of the jetty; (b) the coastal structures alternative will retain beach fill longer, resulting in lower erosion rates from 0.5 to 4.0 mi south of the jetty; and (c) the coastal structures alternative feasibly extends the normal beach nourishment interval from the current two years to four years.
Presenter Bio: Dr. Kabiling has more than 25 years of experience with advanced expertise in water resources, hydraulic and coastal engineering, numerical modeling, and climate change resiliency. His project experience includes the application of one-, two-, and three-dimensional hydrodynamic, advection-dispersion, sediment transport, morphology models. He has applied these models on more than 25 hydraulics and scour studies in Florida, South Carolina, and Louisiana and more than 65 numerical modeling projects in hydrology, hydrodynamics, waves, riverine and coastal flood, dam break, water quality, contaminant transport, sediment transport, morphology, and sea level rise.
Refined Coastal Modeling and Engineering Analysis for the Carolina Beach Coastal Storm Damage Reduction Project
Zhanxian Wang, Moffatt & Nichol
Co Authors: Nicole Vanderbeke, Brandon Grant, Layton Bedsole
The Carolina Beach (CB) Coastal Storm Damage Reduction (CSDR) project has been successful under the US Army Corps of Engineers (USACE) management; however, improvements to the shoreline and project performances may be feasible. In an effort to assess the CSDR project, New Hanover County and the Town of Carolina Beach authorized a Refined Coastal Modeling study to evaluate potential alterations in the design template. The analysis evaluates the project performance to provide guidance on future management options in the event the County must solely design, manage and implement future maintenance events.
The refined modeling analysis utilizes a set of state-of-art coastal engineering modeling platforms including GenCade, Delft3D and SBEACH to evaluate the respective shoreline evolution, longshore transport, morphological change, and cross-shore storm impacts. The GenCade model is used to estimate the shoreline position, while the Delft3D model aids in estimating the annual volumetric change for each alternative. The SBEACH numeric model provides the assistance necessary for the cross-shore storm impacts analysis.
The modeling analysis reviews the performance of seven design alternatives, including the template utilized by the USACE in the 2016 maintenance event. The alternatives adjusted the fill placement volumes and locations to evaluate the resulting sediment transport and shoreline migration using the Delft3D and GenCade models. The analysis also estimated the Level of Storm Protection provided by each alternative. The analysis compares the multiple design alternatives against the current management strategy (USACE template) to estimate potential betterments available in the volumetric trends and shoreline migration benefits as well as the potential economic risk should routine maintenance events falter.
Presenter Bio: Dr. Wang has over 15 years of experience in coastal hydrodynamics, sediment transport, shoreline change, beach nourishment, coastal structures, and numerical modeling techniques. He is currently working at Moffatt & Nichol’s Raleigh Office.
Coastal Processes Study and Structure Design for Bay Breeze Park
Long Xu, McLaren Engineering Group
Co Authors: Stephen Famularo, Olabisi Kenku, Nathaniel Harrisr
Coastal Processes Study and Structure Design for Bay Breeze Park
Long Xu, P.E., CFM, McLaren Engineering Group
Stephen Famularo, P.E., D.PE, McLaren Engineering Group
Olabisi Kenku, McLaren Engineering Group
Alison Shipley, Quennell Rothschild & Partners
Nathaniel Harris, RLA, Quennell Rothschild & Partners
The Rockaway Parks Conceptual Plan by the New York City Department of Parks and Recreation (NYCDPR) was created post Hurricane Sandy to “create a long-term vision that integrates resiliency and enhances community protection” through the replacement of facilities that were destroyed, and improvement of existing parks within the Rockaway Peninsula and Broad Channel. Bay Breeze Park was identified as one of the Bay Side Parks in the conceptual plan. The site is located within Jamaica Bay on the north shore of Rockaway Beach along Beach Channel Drive between Beach 89th Street and Old Beach 88th Street. The project site spans approximately 700 feet along the Jamaica Bay.
To support the intent of the shoreline design which is to incorporate “…resilient design features that will protect the community against frequent flooding from Jamaica Bay”, the coastal processes which result in beach erosion in the area must be studied firstly. Wave and sediment transport models were developed for the waterfront of Bay Breeze Park to characterize littoral transport processes. Simulations of average conditions and storm events were run for these models in order to gain a good understanding of the existing conditions. Riprap structure design along the beach was provided to protect the beach and park from wave and flooding damage. Cross-shore sediment transport model was set up and applied to understand the impacts of storms and sea level rise (SLR) and evaluate restoration alternatives to improve the stability of the shoreline protection system. The final conceptual design which comprises of a proposed riprap and beach nourishment profile will aid in the stabilization of the beach shoreline and the protection of the park amenities.
Presenter Bio: Mr. Long Xu, PE, CFM, is a Senior Coastal Engineer of Marine Division at McLaren Engineering Group. He received a Master’s degree in Coastal Engineering from the University of Delaware’s Center for Applied Coastal Research. Mr. Xu has 13 years of diverse professional experience in the fields of coastal science and engineering, coastal processes, coastal structure design, and FEMA coastal flood hazard study. His areas of expertise include numerical modeling of tide, wave, current, storm surge, and sediment transport.
Land use above sea level rise: The importance of floodplain management
Paxton Ramsdell, Environmental Defense Fund
Co Authors: Will McDow
The nation’s coasts are fundamentally connected to and influenced by inland land uses, communities and the freshwater rivers that flow through them as they meander to the ocean. Nowhere is this more apparent than on coastal plain geographies. These landscapes are often wet, including rivers, marsh and wetland ecosystems, and their flat geography and rich soils make them ideal for agricultural production. Often overlooked as a key influencer of coastal health, the management of coastal plain landscapes has important implications for sea level rise, near-shore water quality and for addressing impacts from extreme weather. In North Carolina, this was seen most recently during Hurricane Florence where both riverine and tidal flooding had significant impacts to inland and coastal communities, landowners and ecosystems.
Using Hurricane Florence’s impacts to North Carolina’s coastal plain and coastal areas as a backdrop, this discussion will bring together on-farm practices and nature-based applications that connect inland floodplain management with coastal and marine ecosystem health.
Presenter Bio: Paxton has spent his career working with individuals and businesses on issues related to sustainability and land and species conservation. He began his career at the Brandywine Conservancy in Chadds Ford, Pennsylvania before spending almost five years at The Nature Conservancy working with multinational businesses. During graduate school, Paxton co-taught an online course for working forestland owners through Virginia’s Cooperate Extension, interviewed ranchers in central Texas about land management practices, and evaluated landowner participation in a ground-nesting bird conservation program. After graduate school, Paxton worked for the Virginia Cooperative Extension to boost landowner awareness of, support for, and adoption of agroforestry practices in the Chesapeake Bay watershed. Paxton also has non-profit governance experience working with the Board of Directors of WWF-US. Today Paxton advances EDF’s working lands and resilience initiatives in the southeast.
Planning for sea level rise in estuaries – experiences from the UK
Nigel Pontee, Jacobs
The UK coastline is dissected by over 170 estuaries that differ markedly in their physical characteristics and management issues. In physical terms, some of these estuaries cover spatial areas as small as 40 acres, whilst a few exceed 125,000 acres. In terms of plan-shape, some estuaries are ‘trumpet-shaped’, some are more like open embayments and others resemble small fluvial inlets. Variation also exists in the physical processes that operate within these estuaries, including the waves, tides, surges and sediment transport. A range of management issues arise since the low-lying estuarine shores, as well as the estuarine waters themselves, are subject to the often disparate requirements of commerce, habitation, recreation and conservation. Over the last few centuries, the presence of high value agricultural land, urban development and critical infrastructure such as ports, roads, railways and power stations, has led to the development of extensive flood defence systems. Increasing urbanization of estuary flood plains, coupled with sea level rise means that flood risk is a critical issue in many UK estuaries.
This presentation will illustrate the UK approach that has been developed over the last 3 decades. The presentation will explain the broader national framework that exists for managing flood and coastal erosion risk over the next century. It will explain how shoreline management plans and strategies have been applied at national and regional scales. The presentation will demonstrate how these approaches help develop sustainable approaches to flood risk management by considering large spatial scales and temporal scales.
The presentation will give examples from two of the largest estuaries in the UK – the Thames and the Humber – where strategic approaches have been developed and applied. It will show how the risks to both the built and the natural environment are being managed and the challenges that typically arise, particularly when trying to implement more adaptive approaches to managing flood risk such as managed realignment. The presentation will show how flood risks are assessed, both now and in the future, and how management interventions are selected. It will show how compensation habitat targets are typically set and how mitigation measures delivered. The presentation will conclude with some thoughts on some of the knowledge gaps that need to be filled to develop improved management of estuaries in the future.
Presenter Bio: Nigel has over 27 years’ experience in coastal geomorphology and management. The majority of his work has been in estuaries and has involved the development of strategic flood and erosion risk management plans, strategic habitat compensation plans, habitat restoration project design and assessment, feasibility assessment of surge barriers and flood storage areas, and geomorphological assessments of future behavior. He is currently working on a review of the Humber Estuary Flood Risk Management Strategy and the implementation of the first 10 year phase of the Thames Estuary Risk Management Strategy. Nigel is the Global Technology leader for Coastal Planning and Engineering in Jacobs and a Visiting Professor at the Natural Oceanography Centre, Southampton.
Next Steps for Urban Flooding- A Report of the ASFPM Foundation Forum
Douglas Plasencia, Moffatt & Nichol
The Association of State Floodplain Managers Foundation funds scholarships, projects, books, events, international collaboratives all centered around the issue of flooding and floodplains. The areas of focus are inclusive of upland and coastal floodplains, and consider both the built and natural environment. In March 2019 the Foundation hosted its 6th Gilbert F. White Policy Forum on the topic of urban flooding and resiliency. The GFW Forum is an invitation only two day meeting that draws on the nation’s top policy thinkers across a broad range of disciplines. As such the findings of the Forum benefit from a cross section of perspectives. Urban flooding is a problem that is going to exponentially increase due to climate and shifts in demographics. What is different about urban flooding as compared to other types of flooding is the urban environment. This presentation will at a high level discuss the work of the Foundation but will then share the findings of the Forum.
Presenter Bio: Doug Is the Chief Operating Officer for Moffatt & Nichol. He has been an industry leader in flooding and floodplain management policy for over 35-years. He has served on several National Academies of Sciences panels on flooding, was a past member of the FEMA Advisory Board to the Director, and has testified before Congress on issues of Flood Policy. He is a past Chair of the (ASFPM) Association of State Floodplain Managers and is the current President of the ASFPM Foundation.
Attracting Impact Investing Capital to Floodplain Management Through Environmental Impact Bonds (EIBs)
Todd Appel, Quantified Ventures
A Convergence of Trends: Today’s water sector is shaped by a number of prominent and concurrent trends. First, changes in climates have brought increasing episodes of catastrophic weather across the world. According to the National Climate Assessment, heavy downpours have become heavier and more frequent; and they predict increased flooding, even in areas where rainfall has decreased. Second, we are seeing an overall decrease in public sector funding, particularly for projects that would make cities more resilient in the face of increasingly unpredictable and damaging weather events. Infrastructure across the country has fallen into disrepair, and traditional finance approaches for improvements have struggled to keep up. The American Society of Civil Engineers (ASCE) gave the country’s infrastructure an overall rating of “D+”, estimating an additional $206 billion per year above current projected spending that’s needed to improve our water, waste management, energy, and transport systems and restore their basic function. If that gap isn’t filled, the ASCE predicts that poor infrastructure will cost the country $3.9 trillion in lost GDP, $7 trillion in lost business sales, and 2.5 million lost jobs by 2025. The third trend is the rise of “impact investing.” Private investors have shown themselves willing and eager to put their money to work on solving environmental and social problems. We are experiencing the greatest wealth transfer in history — and the generation on the receiving end is interested in social and environmental outcomes, as well as financial return. The good news is that there is a lot of money from these impact investors waiting to be harnessed for good.
Environmental Impact Bonds
In 2016, Quantified Ventures pioneered the world’s first Environmental Impact Bond, a $25 million Pay for Success (PFS) transaction with DC Water — a public-private entity that distributes drinking water and collects and treats wastewater for more than 672,000 residents and 17.8 million annual visitors in the District of Columbia. The transaction financed green infrastructure projects on 20 acres in Washington, D.C., as part of a broader proposed 365-acre investment. This new financing mechanism allowed DC Water to shift the performance risk of its green infrastructure project to impact investors, thus enabling them to make the “innovative” and green choice over “business as usual.” As a result, rather than paying for “process” — investing in a project and hoping the desired outcomes will result — DC Water will pay for actual measured outcomes that have both human health and environmental consequences. The issuance received extensive media attention and interest from a wide variety of players — from the bond market to the impact investment field to major philanthropies — as it demonstrated a scalable, data-driven approach to bringing private capital to environmental projects across the country.
We are now structuring and deploying Environmental Impact Bonds across the country to address a wide variety of water infrastructure challenges, including flooding which will be the main focus of this presentation.
Presenter Bio: Todd brings decades of experience in organizational transformation, performance management, and multiparty deal structuring, working with numerous government departments in the U.S. and Europe. As Managing Director, Todd leads client delivery across all of Quantified Ventures business verticals. He has led the launch of several Environmental Impact Bond projects, including closing the first publicly offered EIB with Atlanta. He focuses on utilizing outcomes-based financing to deploy green infrastructure and other resilience investments, improve energy efficiency, address water quality issues through on-farm management practices, and promote sustainable urban wood economies. Prior to Quantified Ventures, Todd led projects domestically and internationally for IBM and PriceWaterhouseCoopers. He is based in Boulder, Colorado – the perfect place for a nature lover like him to bike, hike, and ski.
Bonner Bridge Submerged Aquatic Vegetation Mitigation
Phillip Todd, Atlantic Reefmaker
Co Authors: Tyler Stanton, Mark Fonseca, PhD, Randy Boyd
As part of the environmental permitting process for replacing the Bonner Bridge over Oregon Inlet in Dare County, the North Carolina Department of Transportation (NCDOT) agreed to mitigate for submerged aquatic vegetation (SAV) by installing the Atlantic Reefmaker (ARM), a wave attenuation structure. The ARM structure is designed to provide a wave shadow by allowing the existing beds of patchy SAV to coalesce. The structure also encourages colonization of barnacles, oysters and other sessile communities, while providing refugia for bait and game fish.
The NCDOT hired CSA Ocean Services (CSA) to determine the best way possible to mitigate for 1.28 acre (0.52 hectare) of SAV impacts associated with the bridge construction. CSA reviewed the Pamlico Sound area near the project for SAV areas to restore. This search determined that there were no existing SAV areas in proximity to the impacts that required restoration, and, in consultation with the resource agencies, that an alternative mitigation source was required.
CSA reviewed eight potential structures in order the most practicable structure to achieve wave attenuation and promote SAV coalescence. CSA studied the feasibility of these eight structures, and weighted several factors in selecting the Reefmaker structure over the other structures. These factors included: installation issues, mobilization issues; maintenance issues; costs; wave attenuation and estimated resilience over 10 years; estimated essential fish habitat (EFH) utility; and, potential site impacts.
CSA conducted a study to determine the location of the mitigation and the length of the structure. The proposed implementation site was a stable shoal that had supported patchy seagrass cover since at least 1998.
Implementation of the ARM structure was completed in January 2017. The goals associated with ARM installation were 1) to provide SAV mitigation for Bonner Bridge replacement and 2) to contribute to the long term effort to develop the best strategy and methodology for SAV restoration in North Carolina. The objective of this mitigation project was to reduce the amount of wave energy within the project site. By reducing the wave energy for the area, models estimated that there would be a more continuous cover of SAV (specifically for the seagrasses Halodule wrightii and Zostera marina to expand), thereby leading to an increase in seagrass acreage while providing other ecosystem services. These services included water quality improvement, aquatic habitat creation, reduced sediment movement and plant community establishment. The wave break proposed in this mitigation plan also created new linkages between intertidal and aquatic environments.
The NCDOT has conducted monthly monitoring of the ARM structure since its installation, while it has hired CSA Ocean Sciences to conduct bi-annual monitoring to record changes of SAV behind the structure. The monthly monitoring reports are designed to study the potential for scour around the structure in the dynamic Pamlico Sound estuary, while the bi-annual reports note the health and coalescence of the SAV, wave attenuation, sediment changes around the structure and sessile life use of the structure.
Presenter Bio: Phillip Todd is the Project Development Coordinator for Atlantic Reefmaker. He has a BS in Biology and a Master of Public Administration. His broad knowledge base of environmental science, engineering concepts, and policy has allowed him to assist numerous clients with designing, permitting, and constructing a wide array of projects over the past 25 years. With Atlantic Reefmaker, he utilizes his background of science and policy to educate coastal interest groups about project’s benefits and is involved from a project’s initial concept development through construction and use analysis.
Geotechnical Considerations for Wetland Restoration Projects
John Laplante, Anchor QEA, LLC
Co Authors: Travis Merritts, Steve Bagnull, Matt Henderson
Construction in marsh environments requires careful planning, a robust understanding of geotechnical characteristics of marsh soils (and imported soils, if any), and close contractor oversight during the work. Design principles for wetland restoration are seldom published, and this presentation will provide a summary of key principles and considerations for embarking on a successful project. We will present lessons learned from wetland restoration and construction projects that were completed in Ocean City, New Jersey. First, we will discuss planning, engineering and construction considerations to stabilize a historically eroding island in the back bay (Great Egg Harbor Bay) of Ocean City, NJ. Results from first phase of the project, which included construction of a 2,700 ft long living shoreline rock sill, and another 1,450 ft of living shoreline oyster castle placement (along low energy side of the island), and considerations for long-term structure performance will be discussed. Then, we will examine lessons learned from an aggregate roadway that was built across a nearby marsh to provide access to a dredged material confined disposal facility (CDF), and that has supported over 10,000 truck trips to date to manage beneficial reuse of dredged materials obtained from the CDF. During initial roadway work, the contractor could not maintain the roadway elevation despite continued placement of roadway fill. A comprehensive geotechnical characterization was conducted, and mitigation measures were implemented so that the road could function as envisioned. Issues encountered during construction, geotechnical investigation and results, and successful mitigation measures implemented to complete the project will be discussed. Finally, we will present a geotechnical framework for successful design and construction for future wetland restoration construction projects.
Presenter Bio: John Laplante is a geotechnical engineer with over 20 years of experience conducting investigations and preparing designs for shoreline restoration projects. His experience includes marsh restoration, soft soils, coastal protection, and engineered shoreline structures for waterfront projects throughout the United States and Canada.
History of Environmental Restoration efforts at Mordecai Island, NJ
Christina Pico, Mott MacDonald
Co Authors: Douglas Gaffney, Jim Dugan
Mordecai Island is an uninhabited marsh island in Barnegat Bay off Beach Haven, New Jersey that supports a variety of marine and terrestrial life. Erosion has been eating away at the site with approximately 26 acres of habitat lost since 1930 (37%). The erosion is predicted to continue due to sea level rise, subsidence, storms, limited sediment supply, and boat wakes. Erosion control methods have been designed and monitored over the past decade to support restoration efforts at the site.
Phase 1 included temporary protection using biologs, spartina planting and high tide bushes. Phase 2 included an offshore geotextile tube sill with spartina planting, and biologs. Aerial photography and shoreline change analysis indicate that the geotextile tube detached segmented breakwaters have reduced the erosion rate from 3-6 ft/yr to approximately zero ft/yr. Phase 3 of the project included the USACE pumping sand into a gap that separated a north section of Mordecai Island from the larger south portion.
Most recently, phase 4 included the construction of various oyster castle breakwater structures by the Mordecai Land Trust. Mott MacDonald led a Wave Monitoring Program on behalf of Mordecai Land Trust to evaluate the wave attenuation ability of one of the breakwater structures. This monitoring aimed to quantify the reduction in wave height due to the presence of the breakwater in order to provide recommendations to increase the effectiveness of the structure at reducing wave energy reaching the marsh edge.
In 2018, wave data was collected over 19 days using a simple and cost-effective method which utilized two wave gauges – one positioned on the seaward side of the breakwater, and the other on the landward side – to collect water level data. The water level data was processed to evaluate energy based significant wave heights and spectral peak wave periods at the structures. The data was further analyzed to quantify the wave height attenuation rates. A second round of wave data was collected in the spring of 2019 to help define site-specific design parameters for use in adaptive management of the site. Local weather was also regularly monitored over the study period, which included tidal, wind, and storm conditions for Barnegat Bay.
Overall, the wave height attenuation rate of the breakwater during submerged conditions was 38% and the attenuation rate during emergent conditions was 52%. Waves approaching from the northwest and southwest were observed bypassing the structure on its landward side. During site observations, waves incoming perpendicular to the structure were seen to wrap around both sides of the breakwater and continue propagating further inland. Using the 2018 data, Mott MacDonald was able to recommend several adaptive management measures that could be implemented to improve the performance of the breakwater. The results of the 2019 data collection will be presented as well as the refined proposed adaptive management measures.
Presenter Bio: Coastal Engineer, Mott MacDonald. Graduate of Stevens Institute of Technology.
Beneficial Use of Dredge Materials for Salt Marsh Restoration in Rhode Island
Andrew Timmis, J.F. Brennan Company, Inc.
Co Authors: Caitlin Chaffee
Sea level in Rhode Island has risen at an increasing rate, particularly over the last 30 years. Observations by the Rhode Island Coastal Resources Management Council (CRMC) in many of the state’s salt marshes, including those at Ninigret and Quonochontaug Ponds, conﬁrm that salt marshes are beginning to “drown in place,” converting to mud ﬂats or open water. Why is this a problem? Salt marshes perform many important functions, including acting as a natural buﬀer against storms and providing protection for communities along our shorelines, filtering nutrients that would otherwise pollute waterways, and absorbing carbon that would otherwise contribute to climate change, and providing habitat for a variety of wildlife.
Shoreline currents have swept accumulating sand into the Charlestown Breachway at Ninigret Pond and the Quonochontaug breachway at Quonochontaug Pond. As sand enters the ponds, it covers eelgrass beds—an important habitat—and makes navigation diﬃcult for commercial oyster farming as well as the many boaters who enjoy the ponds’ abundant resources such as fishing, clamming, and hunting.
To resolve these problems, the CRMC and their partners designed two projects that used sediment dredged from breachway channels to build up the elevation of adjacent marshes. The projects’ goals included: preserving the functions of the existing salt marshes, increasing the areas’ resilience to future sea level rise and storm events, slowing the entry of sediment into the ponds, improving the ponds’ water quality, and enhancing navigation by creating deeper breachway channels.
The projects at Ninigret and Quonochontaug Ponds were the first of their kind in Rhode Island and New England. The designs required dredging a total of approximately 140,000 CY of sand from the breachway and pond navigational channels. Two 8 IN swinging-ladder dredges removed this material and pumped it onto the adjacent marshes to build up the elevations. Due to the environmental conditions of the marshes and the necessity of accessing remote locations, amphibious equipment was used to move the dredge discharge pipes as well as to spread and shape sand as required. Careful work during the entire process prevented impact to the local eelgrass beds and commercial oyster beds. After sand placement was complete, CRMC and Save the Bay worked with volunteers to install final drainage features and coordinated community events to plant native grasses and shrubs.
This presentation will review the development of the dredging and restoration design, demonstrate how the work was performed to meet project goals, and discuss lessons learned and future design requirements. The presentation will also show how the marshes improved following completion of the work and will summarize the community and environmental benefits of the projects.
Presenter Bio: Andrew Timmis is the Director of Business Development – Environmental Group for JF Brennan. His primary responsibility is the development of privet sector environmental projects for JF Brennan. Mr. Timmis has a BA from Plattsburgh State University College in Environmental Resources Management and Planning. He started his career as the youngest full time Town Planner in the country in Waterboro ME. Over the past 30 years he has worked for a number of environmental remediation companies including Griffin Dewatering, Clean Harbors, Marcor, D.A. Collins and Cashman Dredging providing technical support for dredging, capping as well as soil and groundwater remediation projects across the country.
He enjoys spending time with his wife and two sons, going hunting and fishing and occasionally golfing.
Findings from a Rapid Instrument Deployment Under Storm Conditions, Atlantic City, New Jersey
Kimberly McKenna, Stockton University Coastal Research Center
Co Authors: Alex Ferencz
It is a general assumption that during an extreme storm event the beach profile erodes. However, in an analysis of New Jersey Beach Profile Network (NJBPN) datasets collected after the passage of Hurricane Sandy, some areas experienced deposition (accretion). This was attributed to profile location with respect to storm landfall, shoreline orientation, and local hydrodynamic conditions. But, no nearshore forcing elements were measured to define the parameters that shaped shoreline response to the storm and demonstrates our general lack of knowledge of wave/sediment transport interactions during such events. To determine the forcing elements that create storm-induced changes of the beach profile, the Stockton University Coastal Research Center (CRC), through funding from the New Jersey Sea Grant Consortium, deployed several instruments in a cross-shore array to measure the hydrodynamic conditions and resultant geomorphic response with emphasis on sandbar movement and wave runup on the beach. The site of the deployment was the beach and nearshore fronting the new Stockton University-Atlantic City campus and about 600 m north of NJBPN 129. Due to the lack of extreme storm events along the New Jersey coastline in the 2018-2019 winter storm season, the team selected rapid deployment for a SSE-driven event that generated up to 3 m waves at 9 seconds for a duration of approximately two tidal cycles. Instruments included two acoustic Doppler current profilers (in -7.4 m and -5.1 m water depths), four optical backscatter units, a single point current meter, two tilt current meters, and pressure sensors. Beach profiles were completed one day before the high wave event, and one day after the waves subsided. Preliminary findings indicate general accretion of the sandbar and intertidal portion of the profile. Data from the instruments will be used to determine wave energy and near-bottom turbidity relationships and will provide insight on when the greatest changes occurred during the storm event. In addition, the data will be used in teaching modules for undergraduate students to learn about oceanographic data collection and analysis.
Presenter Bio: Kimberly McKenna is the Director of Sponsored Programs and Senior Project Manager at the Stockton University Coastal Research Center with over 25 years’ experience working in coastal processes research and shoreline management. Ms. McKenna is a registered professional geologist (DE & TX), receiving a Master of Science degree in Geology at the University of South Florida. She has authored several publications including those used as the scientific basis in the development of state legislation, rules, and funding programs as well as peer-reviewed articles and reports regarding coastal processes, shoreline changes, sand sources, and regional sediment management.
A Geotechnical Perspective on Coastal Erosion Processes during Hurricanes: Lessons learned from Hurricanes Harvey and Irma in 2017
Nina Stark, Virginia Tech
A Geotechnical Perspective on Coastal Erosion Processes during Hurricanes: Lessons learned from Hurricanes Harvey and Irma in 2017
Nina Stark, Navid Jafari, Nadarajah Ravichandran, Stephanie Smallegan, Jens Figlus, Iman Shafii, Patrick Bassal, Inthuorn Sasanakul, Luis Arboleda Monsolve
Teams from the NSF-funded Geotechnical Extreme Event Reconnaissance Association (GEER) deployed during the hurricane season in 2017 to investigate impacts from Hurricanes Harvey, Irma, and Maria. In the cases of the former, some teams specifically focused on the coastal zone. Here, lessons learned based on observations stretching from Corpus Christi to Galveston, Texas, during Hurricane Harvey, and stretching from Cape Coral to Key West, Florida, during Hurricane Irma will be presented. In Texas, coastal erosion on barrier islands including dune toe erosion and overwash, scour at bridge piers and at sheet pile walls, undermining of a beach access road, and damage to coastal infrastructure such as piers and jetties were documented. Particularly, the interruption of natural dune lines by access roads was found to potentially weaken the coastal defense system. Also, the development of a scour runnel in front of a sloped boulder seawall was investigated. The scour runnel did not lead to a failure of the seawall, but possibly to first displacements of some boulders. In southwest Florida, Hurricane Irma caused significant beach and shoreline erosion in some locations as well as significant impacts from overwash deposits in others. Gaps in natural defense systems such as vegetation seemed to amplify such impacts. Most beach erosion in the city limits of Key West was found at a small beach pocketed between large structures. Other observations included severe scour at beach structures and the failure of seawalls. The latter was particularly severe in the canal system of Cape Coral. In summary, impacts appeared particularly severe in areas of strong interaction with the built environment as well as where gaps existed in natural defense lines. Severe erosion was often associated to scour or subsequent failure in response to surficial erosion. More detailed investigations targeting the interaction between geotechnical parameters and erosion, scour, and subsequent failure processes for some of the visited sites is still ongoing. Although detailed analysis of these data are still ongoing, lessons learned include the importance of collecting quantitative and qualitative data as early as possible to prevent loss of the extremely perishable geotechnical impacts.
Presenter Bio: Nina Stark received her MS in Geophysics in 2007 from the University of Muenster, Germany, working with the German Naval Research Institute for Underwater Acoustics and Geophysics on mine burial prediction. In 2011, she received her PhD working on the in-situ geotechnical investigation of sediment remobilization processes at MARUM-Center for Marine and Environmental Sciences at the University of Bremen, Germany. Nina joined Dalhousie University, Canada, as a postdoctoral fellow in 2012 after continuing some of her PhD work as a postdoctoral fellow at MARUM. She joined Virginia Tech as an assistant professor in 2013. Her research is focused on coastal geotechnics, coastal and marine field surveying methods, subaqueous sediment dynamics, beach trafficability, and ocean renewable energy. Nina has co-led teams for the Geotechnical Extreme Events Reconnaissance (GEER) association in response to Hurricanes Harvey and Irma in 2017. She has received the NSF CAREER award and the ONR Young Investigator award in 2018.
Proactive Beach Managment Planning and Storm Responses at Holden Beach, NC
Francis Way, ATM
Co Authors: David Hewett, Christy Ferguson, Steve Mercer
The Town of Holden Beach completed a 4.1-mile engineered beach design project in 2017 which exceeded coastal storm reduction expectations during the 2018 hurricane season. This Coastal Storm Damage Mitigation Project, also known as the “Central Reach Project,” was constructed sequentially with a Lockwood Folly Inlet Navigation Maintenance Project (Eastern Reach), using beneficial placement of beach compatible sand to provide protection, increase tourism, habitat, and resiliency, despite the challenges presented by Hurricane Matthew prior to the start of construction. The $15 million dollar venture was locally sponsored. A project of this scope was unprecedented for the Town and required multiple sources of funding to be leveraged. Funding included: multiple FEMA allocations in one project, special obligation bonds, a tax increase for citizens, and the introduction of a new municipal service district. Constructing the Central Reach project simultaneously with the Eastern Reach required increased levels of attention to detail and creative problem solving.
The resiliency of the Central Reach and Eastern Reach was tested by Hurricanes Michael and Florence. Damage totals in sand loss reached approximately 1.13 million cubic yards in the Central Reach area, with mitigation estimates in the $25 million dollar range; however, the project was instrumental in protecting vegetation, dune systems, and infrastructure. This allowed the town to regain operational capabilities within three days post storm. The Central Reach Project required years of planning and permitting efforts to produce a solution to storm damage reduction and a beach nourishment project which could be a source of pride. Future efforts to remediate losses will require similar coordination. Challenges include damage estimates larger than quantities contained in the currently permitted sand source, an artificial reef placement that will compromise usage of the source for future projects, and a concentrated effort to combine funding sources.
The presentation will focus on the Central Reach and Eastern Reach’s engineering and design components; explain how the town was able to finance the project locally; discuss the challenges and successes of the project; highlight project aspects which allowed for emergency preparedness in the face of back to back storms; and describe the benefits of investing in sand fence and vegetation pre and post storm.
Presenter Bio: Mr. Way is a Senior Coastal Engineer in ATM’s Charleston, SC office with more than 19 years professional experience in coastal, environmental, and water resources engineering. He specializes in coastal and water resources analyses and permitting, modeling, beach nourishment, dredging and navigation studies, and shoreline stabilization projects. Mr. Way earned a MS in Ocean Engineering from Texas A&M University in 2000 and a BS from Boston College in 1993. He is licensed as a professional engineer in South Carolina and North Carolina.
Development of Storm Impact Forecasting System for NC 12 Highway along Pea Island, North Carolina
Russell Nasrallah, North Carolina State University
Co Authors: Elizabeth Sciaudone, Alireza Gharagozlou
Extreme storms, such as hurricanes and nor’easters, frequently hit the coast of North Carolina, with significant impacts on communities and their transportation systems. The North Carolina barrier island chain known as the Outer Banks is especially vulnerable to storm surge and high ocean waves accompanying these storms. Consequently, Highway NC 12, which extends along Hatteras Island, is one of the most vulnerable coastal roadways in the state. The only protection for this piece of critical infrastructure is a system of dunes which runs the length of the Outer Banks and protects the roadway from oceanside erosion. NC 12 serves as the only terrestrial evacuation route for the 4,000 year round residents on the island and the 50,000 weekly visitors during the summer tourist season. The aim of this project is to develop a forecasting system to predict adverse roadway conditions due to storms along NC 12 on Hatteras Island. This system will provide detailed information about predicted erosion and overwash over the length of the study area several days ahead of potential storms. The eXtreme Beach (XBeach) numerical model is used to simulate storm impacts along the coast by modeling hydrodynamic and morphological processes in the nearshore and over the barrier islands. This effort is assisted by high resolution digital elevation data provided by the North Carolina Department of Transportation. This presentation describes the validation of a 1-D XBeach modeling system for NC 12 on Pea Island, using Hurricane Sandy as a test case as well as a verification of the calibrated model. These steps are critical to ensure that the numerical model is well suited for the specific environment and a variety of storms. Subsequent steps will involve utilizing detailed forecasting data from the National Oceanic and Atmospheric Administration produced by the Nearshore Wave Prediction System as inputs into the model for updated predictions along Pea Island, NC every 6-12 hours. This information could inform evacuation measures and aid NCDOT in choosing which locations to focus emergency response before and during storms to better defend Highway NC 12.
Presenter Bio: Russell Nasrallah is a graduate student at North Carolina State University. He attained his undergraduate degree in environmental science at Appalachian State University where he first became interested in issues facing coastal environments and communities. After working in renewable energy for 2 years, he decided to pursue his master’s degree at North Carolina State University in coastal engineering with a focus on coastal hazards and numerical modeling. He hopes to help create tools which will help stakeholders and community planners make critical management decisions.
The Little Guy, how not to get stepped on and trampled over during a disaster
Adam Emrick, City of Conway
The City of Conway, SC experienced catastrophic flooding in 2015 with Hurricane Joaquin, 2016 with Hurricane Matthew, and the worst flooding in the history of the City in 2018 with Hurricane Florence. Each of these disasters required coordination and cooperation with Federal, State and County authorities, however, none so much as during Hurricane Florence. Adam Emrick, the City Administrator for the City of Conway, will discuss his City’s struggles with these larger authorities, often at the express expense of his City and its residents.
Presenter Bio: Adam Emrick is the City Administrator for the City of Conway, South Carolina. He was the Planning Director for the City prior to being named to his current role. From 2007 through 2015, he was a Senior Planner with Horry County, South Carolina. Adam practiced law in the metro-Atlanta area from 2000-2007 at the firm of Emrick & Sanders, LLP where he represented hundreds of clients in all areas of the law. He served as a board member and officer in the Stone Mountain Village Merchants Association, Main Street Stone Mountain, and the Downtown Development Authority of the City of Stone Mountain and briefly served as the Executive Director of both the DDA and MSSM prior to relocating to Coastal South Carolina. Adam is a member of the Waccamaw Sertoma Club and the School Improvement Council for the Academy of Arts, Science and Technology. He volunteers for countless events with Conway Downtown Alive and coaches youth sports for the Conway Recreation Department.
Playing well in the sandbox: Interagency Collaboration and Coastal Resiliency
Eric Poncelet, Kearns & West
Co Authors: Jason Gershowitz, Kyle Vint
Successfully designing and implementing local coastal resiliency projects is complicated not only by the uncertainties coming from such risks as Sea Level Rise but also because of the great diversity of stakeholders that are necessarily involved in these efforts. Key among these stakeholders are the diverse range of agencies at the local, state and federal levels who are involved from planning, policy, regulatory, and permitting perspectives. These agencies are all driven by their own distinct institutional missions, interests, and mandates. Their approaches are also informed by their previous histories of working together. All of these factors complicate their abilities to coordinate and collaborate effectively.
This session addresses this challenging dynamic by bringing together a broad range of panelists who represent some of the key players involved in planning, permitting, and implementing coastal resiliency projects. The panel will include representatives from:
The panel moderator will invite panelists to reflect on their involvement in past coastal resiliency projects and respond to the following questions:
o How does interagency coordination typically take place?
o What worked well or didn’t work well?
o Describe challenges and how these were addressed and overcome (or not).
o Describe keys to success.
The session will be organized to involve dynamic dialogue among the panel members. The moderator will also invite members of the audience to share their own related challenges and best practices in dialogue with the panel.
Presenter Bio: Eric Poncelet, Ph.D., is a Principal and Senior Mediator with Kearns & West, a stakeholder engagement and public involvement firm in San Francisco, CA. Eric has been bringing together diverse stakeholders to address complex natural resource management and environmental issues for 20 years. His projects focus on such issues as sediment management, climate adaptation, coastal resiliency, and ocean planning. Eric has a B.S. in Mechanical Engineering from Cornell University and a Ph.D. in Cultural Anthropology from the University of North Carolina – Chapel Hill. He has published widely on the topic of environmental conflict resolution, including the book Partnering for the Environment: Multistakeholder Collaboration in a Changing World.
The Power of Partnerships in Coastal Restoration
Justin McDonald, U.S. Army Corps of Engineers, Mobile District
This presentation will highlight the value of collaboration and partnerships in the successful execution of the Mississippi Coastal Improvements Program along the northern Gulf Coast. In particular, the presenter will discuss the importance of how candid and collaborative engagement across a diverse range of stakeholders and agencies (both federal and state) was critical in the planning, design, and implementation of the $439 million project to restore the barrier islands off the coast of Mississippi. Despite the fact that the numerous stakeholders and agencies involved in the effort had differing perspectives and governing missions (that were sometimes in direct conflict with each other), the effort was successfully implemented and ultimately strongly supported by all parties involved. This is truly a success story that displays how positive outcomes can happen when people are willing to work hard, be honest with each other, listen to the perspectives of others, and strive for collaborative, win-win solutions.
Presenter Bio: Justin McDonald currently serves as the Coastal Resiliency Program Manager for the U.S. Army Corps of Engineers, Mobile District. He leads highly skilled teams of engineers and other scientists in the planning, engineering, and design of complex, multi-million dollar coastal restoration and resilience projects across the region. He has over 17 years of experience in the areas of coastal, hydraulic, and hydrologic engineering as well as dredging and coastal construction contract management. He has a Bachelor of Civil Engineering and a Master of Science in Civil Engineering from Auburn University. He is a registered professional engineer in the State of Alabama.
Made to Order: North Carolina’s Climate Risk Assessment & Resiliency Plan
Tancred Miller, Coastal & Ocean Policy Manager
NC Division of Coastal Management
Department of Environmental Quality
North Carolina’s Cabinet agencies are collaborating under Gov. Roy Cooper’s Executive Order 80 to produce a Climate Risk Assessment and Resiliency Plan for the state. The agencies are not only collaborating with each other, but are also engaged with non-Cabinet agencies, the academic community, local governments, and nongovernmental organizations. The Plan is expected to include recommendations for integrating climate adaption into the policies and programs of the Cabinet agencies. Work on the Plan commenced in March 2019, with the final Plan due by March 1, 2020.
Presenter Bio: Tancred Miller is the Coastal & Ocean Policy Manager for the Division of Coastal Management, and the division’s lead on resilience and adaptation. Tancred coordinates the Coastal Resources Commission Science Panel’s Sea Level Rise Assessment Reports, with the next report due in 2020. He is DEQ’s program designee to the Governor Cooper’s Climate Change Interagency Council, which was created to fulfill the Governor’s Executive Order 80 directives. He holds a Bachelor’s degree in Business Administration from Morehouse College in Atlanta, and a Masters in Coastal Environmental Management from Duke University. He joined the Division of Coastal Management in 2003.
BOEM’s Sand Management Working Groups
Doug Piatkowski, BOEM
BOEM’s MMP leases sand, gravel and/or shell resources from federal waters on the Outer Continental Shelf (OCS) for shore protection, beach nourishment, and wetlands restoration with vigorous safety and environmental oversight. In recent years, there has been a growing demand for OCS sediment for planned projects, as well as for emergency needs to restore areas damaged by natural disasters. Given competing interests in use of finite sand resources coupled with the significant number of other ocean users (e.g., energy infrastructure, fiber optic telecommunication cables, electrical transmission lines, and fisheries), BOEM strives to reduce or eliminate the potential for multiple use conflicts or environmental impacts that could result from marine minerals projects through proactive resource stewardship initiatives. BOEM holds meetings several times a year with regional sand management working groups (SMWGs) to discuss current coastal restoration issues, concerns and challenges. Through these meetings BOEM strives to collaborate with stakeholders and promote resilient and sustainable approaches to the management of marine resources in an ecologically sound manner.
Presenter Bio: Doug Piatkowski is a marine biologist at the Bureau of Ocean Energy Management’s Headquarters office in Sterling, VA. Doug provides environmental policy guidance, direction, and supervision for environmental assessment and consultation activities related to Marine Mineral Program (MMP) leasing decisions in the Outer Continental Shelf (OCS). Current responsibilities include evaluating impacts of OCS activities on the environment in accordance with environmental laws such as the National Environmental Policy Act, Magnuson Stephens Fishery Conservation and Management Act, Endangered Species Act, Marine Mammal Protection Act, etc. Doug also develops and manages environmental studies to inform decision making within the MMP.
Science to Serve Coastal Communities in SC
Susan Lovelace, S.C. Sea Grant
The South Carolina Sea Grant Consortium considers facilitation to be a key aspect of our mission to provide coastal science to our state. The Consortium is comprised of many of the science makers in our state, who, together with our staff, learn and interpret the information needed to sustain healthy and resilient coastal ecosystems, coastal development, fisheries, and businesses. The Consortium, often working with partners, provides technical assistance to municipalities and other local organizations to improve understanding and response to local flooding from extreme rain events, tropical storms and tides and by enhancing local natural assets for improved resilience. Several recent experiences will be shared.
Presenter Bio: Susan is the Assistant Director for Development and Extension at the South Carolina Sea Grant Consortium. She develops partnerships and programs to meet the needs of coastal communities and leads a vibrant extension team focused on resilience and adaptation, nature-based tourism, natural asset planning, environmental quality and living marine resources. A social scientist, Susan teaches in the Masters of Environmental and Sustainability Studies Program at the College of Charleston. She has a B.S. in Zoology from North Carolina State University, B.S. in Science Education from East Carolina University and a Ph.D. from East Carolina University in Coastal Resources Management.
The Fate of Beach Nourishment Sand on the Florida East Coast
James Houston, U.S. Army Engineer Research and Development Center, Corps of Engineers
Over 100 million cubic yards of sand has been placed on Florida east coast beaches since the start of wide-spread beach nourishment in 1970. What has been the fate of this sand? Has it largely disappeared as some suggest or has largely remained in place, increasing beach width to the degree expected?
The presentation will show the remarkable result that based on measured data, 90% of beach nourishment sand placed on this 360-mile coast since 1970 remains on profiles in the active littoral zone. Nourished beaches have widened on average 120 ft and adjacent beaches that have never been nourished have widened by 50 ft due to longshore transport moving nourishment sand to them. About 10% of the sand has been lost to inlets that have been modified for navigation since 1970. Profiles have easily risen much faster than needed to offset sea level rise.
There are not bathymetric measurements with sufficient accuracy to track beach nourishment sand movement over decades. However, equilibrium profile theory relates shoreline change to sand volume gained or lost to the active littoral zone and also to sea level rise. Data of sand volumes gained or lost due to beach nourishment, longshore transport, and inlets are available as is sea level rise since 1970. The effects of these processes on shoreline change are determined and compared to measured shoreline change to determine the fate of beach nourishment sand.
Using equilibrium profile theory, shoreline change, ΔX, due a beach nourishment volume, ΔV, can be estimated by the following equation:
Similarly, the shoreline change, ΔX, caused by relative sea level rise, ΔS, can be estimated by
ΔX= (- (ΔS* W))/((h+B))
Volumes of beach nourishment, ΔV, and designed berm elevations, B, are taken from three 2018 Florida Department of Environmental Protection (FDEP) publications. Closure depth, h, in each county is taken from Houston and Dean (2014). Relative sea level rise, ΔS, is determined using NOAA tide gauge data. The distance from the berm to closure depth, W, is determined using measured FDEP survey profiles. Measured shoreline change data are from FDEP (2018). The presentation will show excellent agreement in each county from 1970-2017 of measured and predicted shoreline change using the two equations.
Shoreline advance produced by beach nourishment has been eight times greater than recession caused by sea level rise from 1970-2017. If beach nourishment sand is placed along this coast at the rate of the past 40 years, the presentation will show that the shoreline will be wider in 2100 than in 2018 for all sea-level-rise scenarios of the Intergovernmental Panel on Climate Change.
In summary, equations based on equilibrium profile theory predict shoreline change from 1970-2017 that compares very closely with measured shoreline change in each east coast county and for the entire coast. About 90% of the beach nourishment is still on profiles in the active littoral zone and has widened beaches as predicted by equilibrium profile theory and easily offset sea level rise.
Presenter Bio: Dr Houston is Director Emeritus of the Army Engineer Research and Development Center, having retired in 2010 after 10 years as both its first Director and Director R&D, Corps of Engineers. He also served as Director of the Coastal Engineering Research Center and the Coastal and Hydraulics Laboratory. He has a Masters and PhD in coastal engineering from the University of Florida, over 200 publications including over 50 journal articles, and many awards including the Morrough P. O’Brien, Bob Dean Research, National Beach Advocacy, Australian Eminent Speaker, and Distinguished Presidential Rank Awards.
Regional Federal and Non-federal Beach Restoration Projects in Vilano Beach, South Ponte Vedra Beach, and Ponte Vedra Beach, St. Johns County, Florida.
Wendy Laurent, Taylor Engineering
Co Authors: Michael Trudnak
Developed areas north of St. Augustine Inlet as well as portions of State Road A1A (SR A1A), the major evacuation route for the region, are vulnerable to storm damage. Chronic background erosion, predominantly from nor’easters, and storm-induced erosion from hurricanes Matthew (2016) and Irma (2017) have undermined the foundations and severely damaged or destroyed numerous shorefront structures. The severe erosion has prompted the construction of many seawalls to protect private residences, emergency truck haul dune restoration by the State of Florida to protect SRA1A, and the beneficial use of inlet maintenance dredging materials to help stabilize the beach.
The U.S. Army Corps of Engineers completed a federal coastal storm risk management feasibility study and environmental assessment for 6.4 miles of shoreline along South Ponte Vedra Beach (3.8 miles) and Vilano Beach (2.6 miles). The study recommended beach restoration within the Vilano Beach reach and a small portion of the South Ponte Vedra Beach reach, but most of the latter reach was excluded due to lack of public beach access. The recommended project includes dune restoration and a 60-ft wide equilibrated berm extension with a 12-yr nourishment cycle. Federal and local funds have been obligated for initial construction, with an estimated cost of $26.5M. USACE plans to use the St. Augustine Inlet flood shoal as the borrow source and is currently conducting the design and permitting phase for the project.
Following the severe impacts from Hurricane Matthew, the Florida Department of Environmental Protection (FDEP) obligated a 50% matching cost share to restore the dunes along the portions of South Ponte Vedra excluded from the federal project. The project will place approximately 20 cubic yards per liner foot of beach along an approximately 5-mile stretch. Due to beach access and construction issues for a truck haul operation, the County intends to use an offshore borrow source for hopper dredging. The USACE feasibility identified an offshore source (Site N-3) located approximately 8 miles directly offshore of the project area. Taylor Engineering, on behalf of S. Johns County, is in the process of applying for federal—Department of the Army permit and Bureau of Energy Management (BOEM) lease agreement— and state permits and analyzing existing data for optimal borrow area design.
St. Johns County is also working with local communities to potentially restore Ponte Vedra Beach, located in northern St. Johns County. The 9-mile stretch of beach has lost an estimated 2.4 million cubic yards of sand since 1986, and recent erosion from hurricanes Matthew and Irma have made many homes vulnerable to future storm damage. Taylor Engineering recently received BOEM authorizations to conduct the reconnaissance phase geophysical and geotechnical surveys to identify a nearby offshore sand source. The sand source investigation is targeting three possible offshore borrow areas, located between 2 and 5 miles offshore in state and federal waters. St. Johns County has initiated plans to conduct feasibility analysis, design and permitting of a beach management project for the area.
Presenter Bio: Ms. Laurent has worked at Taylor Engineering for over two years since receiving her graduate degree. She received her B.S. in Ocean Engineering from the University of Rhode Island and her M.S. in Civil & Environmental Engineering from the University of Rhode Island.
Promoting Science- based Dune and Beach Management at the Local Government level
Frank Hopf, Self
Amelia Island is a developed barrier island off Northeast Florida whose 13 miles of sand beaches and dunes rely on beach renourishment projects to supply sediment. It’s 22,000 or so residents rely for protection from storm waves almost exclusively on a naturally formed dune system. This dune system provides varying degrees of protection along its’s length. Late in 2018, the City Commissioners of the City of Fernandina Beach, the north half of the island, requested that a dune and beach management plan be prepared for their review and approval. This main points of the plan submitted will be reviewed, detailing how it attempted to answer the 2016-2018 ASBPA Strategic Plan call more involvement by coastal and beach managers in directing focus of academic research on dune management and to provide them with improved access to the latest academic research on dunes. The paper will also discuss the ongoing challenges to meeting 2019-2021 Plan goals of having at least 100 coastal communities using science-based decision-making, based on ASBPA Science and Technology tools and achieving the objective that all coastal sediments will be managed as a resource to keep it within the littoral system. Applicability of the plan for other coastal communities will also be review as well as the political challenges to implementing referenced ASPBA goals at the local government level
Presenter Bio: Frank Hopf earned a BS in Civil Engineering before embarking on a 35 year career in engineering and management in the petrochemical industry, earning a MBA along the way. In 2004, he retired to pursue a Ph.D. at Texas A&M University, studying process geomorphology. After completing his studies at age 64, he taught geology and engineering geology courses at Texas A&M from 2012-2015. He retired a second time To Amelia Island, Florida to enjoy what he thought was wonderfully natural beach and dune system there. Hurricane Matthews’s brush with the island’s dunes and the public lack of appreciation of the dunes made apparent in the aftermath made him realize he needed to join the ASBPA and become involved in local education and political processes relating to the dunes and beach.
A Commitment to Coastal Protection, The City of Vriginia Beach, Virginia
James White, City of Virginia Beach
Co Authors: Dan Adams
The City of Virginia Beach is the southeastern most city in the Commonwealth of Virginia. The City is bound by the lower Chesapeake Bay to the north and the Atlantic Ocean to the east. There are approximately 12 miles of Atlantic Ocean beaches and 5 miles of Chesapeake Bay beaches that the City manages. Virginia Beach has grown from a small resort town with an adjacent farming community into a premier city of tourism, business, military and residential living. The City has long lived with, and adapted to, the constant threat of harsh weather and geomorphologic changes. Therefore, the City utilizes a beach management plan to implement and meet the goals that protect and preserve the infrastructure and communities along the coastline. The primary goals of the beach management plan are to provide storm damage reduction, protection of the coastal infrastructure, preserve the tax base, and maintain the valued public recreation and tourism along the beaches
There are four beachfront communities along Atlantic Ocean shoreline and four bayfront communities along the Chesapeake Bay shoreline that the City manages. The beaches range from the 5 mile popular tourist destination of Virginia Beach known as the ‘Resort Beach’, to the quiet 1 mile, predominantly residential, bay beach community of Chesapeake Beach. Historically, only the Resort Beach received any type of beach nourishment. Sand was either truck hauled or hydraulically placed along the Resort Beach. The other Atlantic oceanfront beach communities and the Chesapeake Bay beach communities were either two sparsely developed or property ownership impeded the ability to conduct a beach nourishment project. However, as the City continued to grow and coastal infrastructure began to age, the City understood it was prudent to address and manage the erosive conditions of all of the beaches within its jurisdiction.
Therefore, opportunities for various funding mechanisms came to light as the City developed and instituted its beach management plan. The City has entered into the Federal Cost Share 227 program partnership with the U.S. Army Corps of Engineers for two of its Atlantic Ocean beaches. Those beaches are: the Resort Beach/North End and Sandbridge Beach. To further assist in meeting the local share requirements for the Sandbridge Beach program, a Special Service District property assessment tax has been adopted. City Capital Improvement Program funding has been made available in recent fiscal year budgets to nourish and manage three of the four Chesapeake Bay beaches along with the Atlantic Ocean front community of Croatan Beach.
Since 2000, the City of Virginia Beach has placed approximately 15,000,000cy of sand on its Atlantic Ocean Beaches and 630,000cy along the Chesapeake Bay Beaches. With over 450,000 residents and over 18 million visitors per year to the City’s beaches, the City of Virginia Beach is committed to providing storm protection and recreational opportunities to the residents and visitors alike.
Presenter Bio: James White, P.E., holds a Bachelors of Science in Civil Engineering from Old Dominion University, Norfolk, Va. (Dec. ’94) and a Masters of Science in Ocean Engineering from Florida Institute of Technology, Melbourne, Fl. (May ’97). Mr. White has worked in Coastal Engineering field since 1996 and is currently a project manager for the Public Works Department – Coastal Section of the City of Virginia Beach.
Beach Recovery & Improvement Project – Luxury Resort, Mexico, An engineered solution for geotextile tube marine structures
Tom Stephens, TenCate Water & Environment
Co Authors: Tom Stephens
Mapping Future Coastal Erosion Due to Sea Level Rise – Expanding a Study in New England
Jeremy Mull, AECOM
Co Authors: Brian Caufield, Elena Drei-Horgan, Lauren Klonsky
Coastal erosion is a hazard that threatens lives, property, and resources along much of the US coastlines. Erosion is generally expected to accelerate due to future sea level rise, putting more communities at risk. Although many agencies have investigated future coastal flooding and inundation due to sea level rise, few have addressed the related but distinct hazard of future shoreline retreat in large regional studies. This is important to highlight because there are several communities at relatively high coastal bluff elevations that are not directly vulnerable to future coastal flooding per se, but are directly vulnerable to future coastal bluff retreat. To help address the distinct risk that erosion poses, many coastal communities have asked the Federal Emergency Management Agency (FEMA) to study the future effects of sea level rise and the Technical Mapping Advisory Council (TMAC) recommended that FEMA begin to produce maps and other products that can help communities understand future shoreline retreat, plan mitigation actions, and ultimately reduce risk.
In response to TMAC’s recommendations, AECOM and CDM Smith partnered to complete a pilot study for FEMA to develop projected coastal erosion hazard maps due to sea level rise in the New England area for several future time periods. The purpose of the pilot study was to develop a technical methodology to analyze historical trends in shoreline change, evaluate multiple future sea level rise projections and timeframes, estimate future erosion rates, develop maps of future coastal erosion hazard areas, and synthesize a technical approach that could be expanded to other areas. The study is currently expanding to include an additional 750 miles of shoreline in New England. The future erosion forecasts are detailed and incorporate differences in shoreline geomorphology (e.g., sandy beach and dune versus erodible coastal bluff), which are important to consider as not all shorelines will respond in the same manner to sea level rise. Sandy beaches will generally erode more quickly than bluffs. In addition, the study incorporated statistical analysis of long-term historical trends in shoreline change (e.g., erosion versus accretion). This is also critical as currently eroding beaches will most likely erode more rapidly than accreting beaches in response to sea level rise. The maps consider multiple sea level rise scenarios and future timeframes to provide stakeholders with key information for planning.
This presentation will review some of the important technical aspects of the study and demonstrate why these are critical in developing accurate future coastal erosion forecasts. The presentation will also discuss updated results and highlight some of the key challenges that have arisen since expanding the study to areas with new geomorphologies and propose some technical solutions to these specific challenges. Finally, there will be a discussion on how communities might implement and use the maps. It is hoped that future studies such as this one can provide information on an important, but understudied risk.
Presenter Bio: Mr. Mull is a coastal engineer with 8 years of consulting experience during an 11 year career in coastal engineering and science. He has a diverse background in engineering, physical oceanography, and coastal geomorphology. At AECOM, he has participated in a variety of projects focused on coastal vulnerability to flooding and inundation, sea level rise and climate change adaptation, tsunamis, structure design, coastal erosion, and shoreline restoration. Mr. Mull is interested in using engineering to help communities and agencies understand and prepare for the hazards associated with erosion, long-term shoreline change, sea level rise, and tsunamis.
A Stakeholder-Driven Prioritization of Coastal Mapping for the State of Florida
Cheryl Hapke, Coastal Science Solutions
Co Authors: Ryan Druyor, Rene Baumstark, Phil Kramer
he Florida Coastal Mapping Program (FCMaP) is a coordinating body of State, Federal and academic partners that has a goal to achieve consistent, high-resolution seafloor data for Florida’s coastal zone in the next decade. These data are envisioned to provide the foundational information for applications ranging from resource management, fisheries, storm surge modeling, boating safety, tourism, and future developments, such as renewable energy and offshore aquaculture. FCMaP developed a strategic plan in order to accomplish the onerous effort of mapping the State’s over 1,300 miles of coastline. The first phase involved conducting a comprehensive inventory and gap analysis, for which the Florida peninsula was divided into six regions based on geomorphological characteristics: Panhandle, Big Bend, West Peninsula, Keys, Southeast, and Northeast. The inventory included 345 datasets, which were also assessed on whether they met certain criteria, such as age, spatial coverage, and resolution. In consideration of differing sensor and survey design requirements, results in each region were grouped into two depth ranges: nearshore (shoreline to 20 meters) and shelf (20 meters to the continental shelf break). The gap analysis revealed that less than 20% of Florida’s coastal waters have been mapped using modern bathymetric methods (multibeam sonar or airborne lidar), and in some areas, less than 5% of the seafloor has modern data; where data do exist, they often date to the 1800s.
In order to address the significant gaps in modern seafloor data, FCMaP is currently undertaking a formal prioritization process that solicits input from managers, planners, and decision-makers to prioritize coastal and seafloor mapping needs. The tool is an online ArcGIS widget, developed by NOAA, and adapted to be a FL-specific, FL-hosted application. The coastal zone of Florida is divided into six regional ten-by-ten square kilometer grids and stakeholders populate the grid with an allocated number of coins to indicate their highest priority mapping needs. Along with the spatial distribution of areas of interest, stakeholders are also asked to indicate why they need the data – what their applications are – and what ancillary data they require for their application. Ancillary data include data types such as backscatter, side-scan sonar, and sub-bottom information. The tool is being introduced region-by-region via a series of stakeholder workshops comprised of representatives from Federal, State, local, academic, and private entities. The workshops introduce the participants to the tool and groups of stakeholders are assigned a user license to access the tool post-workshop. Analysis of the input from the stakeholders generates a cumulative prioritization for the region that can be displayed as a map product, and the associated justifications for the priority areas are statistically evaluated.
Presenter Bio: Dr. Cheryl Hapke is a coastal geologist at USF College of Marine Science and owner of Coastal Science Solutions. She spent 20 years as a research scientist with the USGS Coastal and Marine Hazards and Resources Program. Her research focuses on understanding coastal evolution and response in a variety of coastal settings including barrier islands, and rocky and mainland coasts. She is currently the Coordinator of the Florida Coastal Mapping Program, a consortium of Florida State and Federal agencies with a goal of realizing modern, high-resolution seafloor data for all of Florida’s coastal waters. Dr. Hapke received her Ph.D. in Coastal Geology from the University of California Santa Cruz, an M.S. in Geology from the University of Maryland, and a B.S. in Geology from the University of Pittsburgh.
Implementation of the ADCIRC tidal database and UTide tidal prediction in the CHS-StormSim framework
Marissa Torres, USACE ERDC CRREL
Co Authors: Amanda B. Lewis, Victor M. Gonzalez, Norberto C. Nadal-Caraballo
The U.S. Army Corps of Engineers’ Coastal Hazards System (CHS) is a national database and web tool that provides probabilistic coastal hazard analysis (PCHA) results of tropical and extra-tropical cyclones to support feasibility studies, probabilistic design of coastal structures, and flood risk management for coastal communities. The Stochastic Storm Simulation System (StormSim) provides coastal storm hazard results (i.e., hazard curves) for storm surge and waves at various locations of interest. Employing Gaussian process metamodels (GPM) trained on CHS data, StormSim can also predict storm surge and concurrent wave climate in real time for forecasting applications. This is made possible by a TC parameterization scheme that can be used to represent both historical and synthetic hurricanes. Both the timing of a hurricane landfall and the level of the astronomical tide at the landfall location are critical in determining the magnitude of the still water level (i.e., storm surge + astronomical tide). Therefore, we need a robust and accurate tide prediction methodology to provide reliable reconstruction of tidal time series for historical, synthetic, and forecasted hurricane scenarios. In practice, the CHS and StormSim will be informed by tidal time series for specified storm scenarios at all save points within the study domain (e.g., the Coastal Texas Comprehensive Study; CTXCS).
We seek to use tidal harmonics produced from the ADCIRC tidal database to inform tidal prediction through the Unified Tidal (UTide) analysis program. We evaluate the “goodness of fit” of the reconstructed tidal time series by comparing to NOAA predictions at 45 tidal gauges in the CTXCS region (TX and LA) over a one-year period (Jan 2018 – Dec 2018). To separate the uncertainties generated within UTide and the uncertainties carried over from the differences between NOAA and ADCIRC tidal harmonics, the tides were reconstructed and compared with NOAA predictions twice, first using NOAA harmonics and second using ADCIRC harmonics. Preliminary error metrics suggest there is more seasonal variability in areas of complex coastal bathymetry that require additional considerations (e.g., number of tidal constituents, model settings) in the UTide program to produce accurate time series. We further highlight the optimal conditions for which consistently accurate tides are produced in the CTXCS region.
Presenter Bio: Marissa Torres is a Research General Engineer with the US Army Corps Engineer Research and Development Center at the Cold Regions Research and Engineering Laboratory in Hanover, NH. She has BS and MS degrees in Ocean Engineering from the University of Rhode Island with a focus in coastal flooding and storm surge modeling. Her research interests include atmospheric, coastal, and wave modeling, hydrodynamics, ocean renewable energy, wave mechanics, and numerical methods.
Developing High-Resolution Data and Neighborhood-Scale Flood Modeling in Charleston County, SC
Landon Knapp, South Carolina Sea Grant Consortium/College of Charleston
Co Authors: Norman Levine
Communities in Charleston County, South Carolina are susceptible to a suite of environmental and natural hazards ranging in type, style, frequency of occurrence, and severity of impact. With the low elevation and vast seaward and estuarine shorelines within the County, no hazard is more tangible to the residents of the region than the dangers posed by flood waters. Sea level rise has long been communicated as a future scenario – something to prepare for; however, rising water levels have already begun to impact the region having an effect on infrastructure, property and dollars. While citizens in Charleston have lived with King Tides and periodic storm events for much of the area’s rich history, the increasing frequency of flooding and damage from these events has highlighted the need for a better understanding of the areas most susceptible to these hazards.
The physical environment of Charleston County presents multiple challenges to traditional hydrologic modeling due to its low elevation, low relief, and abundance of water features. In addition, the high density of development in much of the county heightens the importance of identifying impervious surfaces, which can often be hidden under the dense tree canopy covering the area. This study adapted traditional flood modeling techniques by developing high-resolution digital elevation, watershed, and impervious ground surfaces for use in hydrologic models; taking into account riverine flooding, sea level rise, and pulsed rain events for neighborhoods in Charleston County, SC.
Novel methodologies were applied to generate 1-meter resolution digital elevation models (DEMs) created from LiDAR data as well as 1-meter resolution impervious cover for each of the 5 neighborhoods chosen (LiDAR-Multispectral Fusion technique). Those products were used to create small, connected “urban watersheds” which were used in modified CN method rainfall-runoff models to detail the movement of water across the area during storm events. Tide gauge data were interpolated across the study area to create a base surface (NOAA VDATUM improved product) from which tidal, sea level rise, and riverine flooding scenarios were developed. These scenarios were incrementally applied and compared to produce flood depths for design storms and varying tidal events. Cumulatively, these flood depth analyses allow decision-makers and citizens to determine the location and severity of flooding events of their choosing. The model presented here reflects a shift in the way data has been used in the past from reactive-based to proactive data driven decision products for response and mitigation.
Presenter Bio: Landon Knapp has more than 10 years of experience in coastal environmental science and management, including time with a nonprofit, in a biological laboratory, and doing research work with the National Oceanic and Atmospheric Administration and S.C. Department of Health and Environmental Control’s Office of Ocean and Coastal Resource Management. In his current role with the South Carolina Sea Grant Consortium and College of Charleston Lowcountry Hazards Center, he provides hands-on operational and technical support to coastal communities, resource managers, and interest groups to foster coastal community resilience.
Hydrodynamic modeling of alternative design scenario for Ocean Drive, NJ
Yi-Cheng Teng, Michael Baker International
Co Authors: Daniel Barone
Ocean Drive and its bridges, located with in the Township of Lower in Cape May County, NJ, were constructed in 1939 and have been repaired and rehabilitated at various times since the original construction. The existing bridge and road elevations are below the effective 100-year BFE as determined by FEMA. Concept development study for Ocean Drive upgrade and improvements proposes to elevate the roads and bridges to be above the effective 100-year BFE. However, the relative local hydrodynamic impacts due to the proposed designs remain unknown. To address coastal hydrodynamic concerns related to the proposed upgrades and bridge improvements along Ocean Drive, a high-resolution hydrodynamic modeling was performed for the study area with a state-of art unstructured-grid model ADCIRC that was fully 2-way coupled with the SWAN wind wave model to study the impact of proposed designs on local hydrodynamics. The high resolution unstructured grid model is capable of resolving the existing and proposed bridge, roadway and culvert structures at order of 5 m in the project area. Model simulations for the project area were first validated with observations and the results indicated that the high-resolution model is capable of simulating both water levels and velocity attributed to the combined forcing of tides and storm effects. The validated model than was employed to study the influence of the proposed designs on local hydrodynamics. Results comparing the maximum water elevation and velocity from 100-year storm simulations reveal that that changes in water elevation and flow patterns due to the proposed bridge, roadway, and culvert designs do not present significant negative impacts to the project area in terms of increased area of inundation or increased velocities during 100-year storm events. This study demonstrates that a high-resolution hydrodynamic modeling can be a powerful tool and provide insightful information in terms of understanding the changes in water elevation and flow patterns during the concept design phase.
Presenter Bio: Dr. Teng joins the Michael Baker International Department of Environmental and Water Resources as a coastal scientist and focuses on coastal numerical modeling and GIS, and other coastal related projects. His expertise includes physical and biogeochemical oceanography, development of numerical models, and data assimilation. He has more than 12 years of experience as an ocean modeler. Before joining MBI, he has been a professor and a principal investigator for multiple projects supported by the NSF, DOE and NOAA. Additionally, Dr. Teng has published his works in prestigious journals such as Nature-Geoscience, Journal of Geophysical Research-Ocean, Ocean Engineering, and Ocean Modeling.
The Influence of the Vertical Current Structure on the Scaling of Wind and Wave Driven Surge Modeling
Amanda Tritinger, University of North Florida
Co Authors: Don Resio
Following Katrina many publications have examined the modeling of surges from tropical cyclones (Brown et al., 2016; Xie, 2017; Ruessink, 2010; Fan et al., 2016; Li et al., 2014; Haas & Warner, 2009; Zheng, et al., 2017). It has become clear that the accuracy of these storm surge predictions is critical to coastal resilience. In this paper a simple scaling proposed by Resio, & Westerink, 2008 is revisited. The need for this revision is prompted by the effect that wind and wave driven currents have on the turbulence structure which significantly effects the bottom stress in surge models. Bottom stress concepts in 2DDI surge models neglect the vertical current structure, which often varies significantly in direction and magnitude from the associated mean current. One consequence of this is the inability of 2-Dimensional Depth Integrated (2DDI) models to represent the bottom stress in the nearshore region accurately. Scaling and an abundance of lab and observational data (Murray, 1975; Shay et al., 1989; Kuroiwa, et al., 1997; Shay, 2010; Falconer, et al., 1991; Kocyigit, & Falconer, 2004, Ting, & Kirby, 1995; Scott, et al., 2005; Uchiyama, et al., 2010) have shown that the simple structure posited by (Resio, & Westerink, 2008) previous scaling analysis, a parametric scaling of surge heights at the coast due to, need to be expanded to include this additional detail.
This should be of high interest to everyone who uses modeled surges for design and planning. Often, calibration of the bottom drag force coefficient is used in hind-casting in order to match observation surge levels, however is has a significant impact on surge estimation of the model and cannot be considered a universal solution. If a model is calibrated to perform optimally on a Texas coast, for example, will do poorly in New Orleans and vise versa. If a model is calibrated for one storm in a given area, it may not be able to capture a storm with varying parameters in that same location. Local calibration prohibits the use of models for universal coastal application. There will always be some calibration of a model, however the need for localized bottom drag coefficient tuning must be addressed, and a solution found so that results are more accurate everywhere, and with less tuning needed. This work will address likely causes of the need to calibrate the bottom drag coefficient and suggest the use of a parametric scaling method for estimating bottom stress values in storm surge estimation models. Results of this investigation found that an additional 50% of surge can be calculated in the nearshore region during extreme storm events if the suggested parametric scaling of bottom stress presented in this study is included.
Presenter Bio: Amanda Tritinger earned her B.S. degree in environmental engineering from the University of Central Florida (UCF) in 2013. In 2015 she received a fully funded M.S. in civil engineering with a focus in coastal modeling degree from the University of North Florida (UNF) under the guidance of Dr. Peter Bacopoulos. Amanda studied under advisors from both schools; Dr. Don Resio (UNF) and Dr. Maitane Olabarrieta (UF). She earned her Doctor of Philosophy in coastal and oceanographic engineering from UF in 2019.
Recent Advances in the Physics of Wave, Surge and Sediment Transport Models
Don Resio, Director, Taylor Engineering Research Institute
Co Authors: Amanda Tritinger, Doruk Ardag, Nikole Ward
Coastal models often become accepted as based on first principles of physics, even though they often mask somewhat significant deviations from the governing equations for the processes they are simulations. Two examples of this will be developed in this presentation to show the importance of research programs which focus on a synthesis of measurements and models; however, it is clear that the tuning for individual events should be performed with more objectivity that many studies conducted with these models.
Example 1 will examine the application of two classes of depth averaged surge models and examine the deviations in these models from careful measurements, the physical reasons for these deviations and the persistence of errors that can be tuned out for a small set of storms but reappear if the conditions are varied for different storm conditions. Examples of ongoing work to address this issue will then be presented, including analyses which show the potential deviations caused by the missing elements within the model physics.
Example 2 will examine problems within the physics contained in existing Third-Generations spectral wave models and will address recent work at the University of North Florida to develop improved, stable, detailed-balance spectral models for a range of coastal applications. This will include the introduction of a new version of a steady-state model for coastal applications, with a new dissipation term for propagation from deep water to the shoreline based on recent publications. Comparisons of model performance to observations from a wide range of sea and swell conditions at Field Research Facility in Duck, North Carolina will be shown using no model tuning. Directional properties of incoming wave spectra, of particular interest to coastal applications, will be examined in some detail, along with the method included within the model to include strong diffraction (i.e. waves propagating past breakwaters and into harbors) within this model.
The presentation will then add a closing discussion of the need to develop robust guidelines for model calibration, with particular emphasis on the importance of objectivity in error assessments for engineering applications in coastal areas. For this reason, it is recommended that additional long-term test ranges of waves and water levels be established in different coastal environments around the United States.
Presenter Bio: Dr. Resio received his PhD in Environmental Science from the University of Virginia in 1974; served 7 years as a researcher at the Waterway Experiment Station; was Vice President of Oceanweather, Inc. (1981-1983); President of his own company Offshore and Coastal Technologies, Inc. (1984-1990); was Associate Professor of Oceanography at Florida Institute of Technology (1990-1994; served as Senior Technologist at the Coastal and Hydraulics Laboratory at ERDC (1994-2011; served as the Director of the Taylor Engineering Research Institute at the University of North Florida (2011-present); and published over 90 journal papers in coastal engineering and coastal risk analysis.
Get the MUCK outta here! Turkey Creek Muck Removal Project (Brevard County, FL)
Robert Baron, Tetra Tech Center for Coastal Services
Co Authors: Mike McGarry
Turkey Creek, an upstream watershed in Brevard County, FL, discharges into Turkey Lake and Palm Bay, the latter of which is connected to the Indian River Lagoon. The Palm Bay and Turkey Lake basins were initially dredged between 1999 and 2001, removing a reported 225,000 cubic yards of fine-grained (silt-clay) deposits. Continued deposition of these muck sediments since that time, as well as degradation of the Indian River Lagoon, prompted the County to consider an environmental restoration project to reduce nutrient loading into the Indian River Lagoon.
Brevard County received a $10 million grant from the Florida Department of Environmental Protection in 2014 to begin a program to improve the water quality of the Indian River Lagoon. The Turkey Creek Muck Removal Project was funded through this program and targeted the removal of up to 330,000 cubic yards of organic rich fine-grained sediment (i.e. muck).
Initial muck dredging operations commenced in February 2016 and extended to April 2016. In March 2016, one of three redundant weir/discharge pipes at Florida Inland Navigation District Dredged Material Management Area (DMMA) BV-52 collapsed, resulting in an uncontrolled discharge of turbid waters into the Indian River Lagoon through the DMMA discharge pipe. Dredging operations immediately ceased and rapid corrective repair measures were initiated.
After the inadvertent discharge resulting from the weir/discharge pipe collapse, followed by repair of the weir/discharge structures, dredging activity recommenced in April 2016 and continued until a permit required shut-down, to avoid manatees from May 1-June 30, was initiated. Following the temporary shut-down, dredging activity continued between September 2016 and January 2017. This initial phase removed 214,374 cubic yards from the project area. The initial dredging completion certification was received in June 2017.
Hurricane Irma impacted Central Florida in September 2017. After the impact of Hurricane Irma, additional muck sediment was found in the Turkey Creek Project area. To address the added muck, a small clean-out dredging effort commenced in January 2018 and completed in March 2018. This post-Irma phase removed 21,682 cubic yards of muck from Palm Bay. The final As-Built Certification was submitted in July 2018. In total, the project removed 236,056 cubic yards of muck from the project area.
Throughout the project, which removed a total of 236,056 cubic yards of sediment, all dewatering activity was completed in the BV-52 DMMA. Material settled with assistance from polymers before being allowed to dry over time to a truckable consistency. Solids were removed from the DMMA and transported by trucks to upland areas for beneficial reuse, primarily on agricultural land in Brevard County.
Presenter Bio: Robert M. Baron, a marine biologist with almost 20 years of experience, has an extensive understanding of marine/estuarine habitats and has experience identifying impacts to these complex systems. Rob manages large scale coastal projects including benthic habitat characterizations, habitat restoration, post-hurricane impact assessments, and artificial reef habitat enhancement projects. As an experienced scientific diver, Rob is Tetra Tech’s Center for Coastal Services American Academy of Underwater Sciences Diving Safety Officer and is proficient in coral reef, natural hardbottom and artificial reef benthic community monitoring and assessments; coral harvest and transplanting; seagrass surveying; in-water fish censusing; and sea turtle monitoring.
Effects of physical beach characteristics on sea turtle nesting and hatching success
Tiffany Briggs, FAU
Co Authors: Sarah Milton, Ph.D., Andrew Medhurst
Coastal development often leads to marine turtle habitat alteration or loss, with nesting areas squeezed between eroding shorelines and coastal development. One of the most common responses to beach erosion in the United States is beach nourishment, given the many benefits, such as storm protection, creation of habitat and recreational space, increased tourism, and protection of buildings and infrastructure. However, knowledge gaps exist in understanding the thresholds of parameters used in the placement of sediments, such as textural and compositional sediment characteristics that might significantly alter the attributes of the physical environment as a habitat. For example, in Southeast Florida, beaches host approximately 17,000 loggerhead and 2,500 nesting green turtles each year. Sea turtle nesting success (relative to false crawls), hatching, and emergence success depend on numerous factors that determine the suitability of the nesting environment, including beach slope and width, sand composition, temperature, grain size, and water potential. This study evaluates the spatio-temporal variability and impacts on successful sea turtle nesting and hatching in Boca Raton, Florida of the physical beach characteristics following a nourishment in 2017 and 2018. Characteristics including sediment texture, composition, beach morphology, and beach inundation had variable impacts on sea turtle nesting, hatching, and emergence success.
Presenter Bio: Dr. Tiffany Roberts Briggs is an Assistant Professor in the Department of Geosciences at Florida Atlantic University (FAU), specializing in coastal geology and geomorphology. Briggs has co-authored numerous research publications on storm-impacts and recovery, beach nourishment, and beach/barrier island morphology. Briggs is co-chair of the ASBPA Science and Technology Committee, and serves on the ASBPA Board of Directors, Executive Committee, and Shore & Beach Editorial Board.
Island Design for Nesting Waterbirds
David Buzan, Freese and Nichols, Inc.
Co Authors: Victoria Vazquez, Nic Kirk, Ray Devlin
Audubon Texas manages islands for colonial nesting waterbirds on the Texas coast. Some islands have been lost to erosion and subsidence over the years, forcing birds to nest on fewer islands. With fewer islands, these birds are more likely to be impacted by catastrophic storms and chemical spills. The National Fish and Wildlife Foundation funded Audubon to identify sites and designs for new rookery islands. The broad goal was to increase resilience of colonial nesting waterbird populations by providing more nesting islands.
Audubon hired Freese and Nichols, Inc. to facilitate its project technical advisory committee, identify four locations for new islands on the central Texas coast, and design new islands at those locations. Freese and Nichols and Audubon collaborated to characterize the nesting requirements of Audubon’s priority species. With input from a multiagency technical advisory committee, 38 potential nesting sites were considered. While this review was ongoing, Freese and Nichols biologists interviewed 19 experts engaged in restoring and creating nesting islands to identify best practices in siting, designing and managing nesting islands.
Surface sediments and bathymetry were collected around potential island sites and Moffatt and Nichol, Inc. modeled the wave and current regime to help understand how the new islands may be impacted by wave attack and erosion.
The technical advisory committee identified important considerations for siting islands including: selecting locations with firm substrates, water depths less than three feet, and far enough from land to prevent easy access by predators like coyotes and raccoons. New islands should also be far enough from other major rookery islands to minimize the probability a catastrophic event would impact all islands on that part of the coast.
One possible location was in the middle of Espiritu Santo Bay. This island would be far from other rookery islands and designed to support Audubon’s priority species including ground and shrub/tree nesting birds. Up to 8 acres in area and armored on three sides, it might be constructed with maintenance dredge material from the Gulf Intracoastal Waterway. This would be the most expensive of the islands to construct with an estimated cost of $13 million.
Three locations were identified in East Matagorda Bay. These islands would be small and low, designed to support priority ground-nesting birds. They may be overtopped by extreme high tides every few years. This episodic flooding every few years would help limit plant growth. Nearby existing islands and shoals would help protect these new islands. The islands would be capped with a six inch to one-foot thick layer of crushed limestone or similar material to provide the stable nesting habitat for birds. Estimated cost of these islands ranged from $3 million to $9 million.
In the course of the project, less expensive potential alternatives like decommissioned barges and constructed rafts or platforms were encountered. Although these would be smaller than constructed islands, they could provide more flexibility in siting new islands at lower costs.
Presenter Bio: David Buzan is a coastal ecologist with Freese and Nichols, Inc.
Living Docks – Restoring Benthic Communities
Robert Weaver, Florida Institute of Technology
Co Authors: Kelli Hunsucker
Our Estuaries are facing a crisis; rising sea levels, eutrophication, and runoff bringing fine sediments, have fundamentally altered the benthos. Coupled with the fact that the keystone benthic filter feeders (e.g. clams and oysters) have been over-harvested, our estuaries have reached a tipping point. To address the issue of declining estuarine habitat, we developed a community based restoration project called the Living Dock Project. Our Living Dock project seeks to increase benthic filter feeders by providing a substrate elevated off the bottom, taking advantage of man-made structures already abundant along most developed waterfront communities. By directly involving waterfront communities, the project seeks to increase the knowledge and understanding of the public, while providing citizens a means to directly become involved in the restoration process. Living Dock modules have been developed by modifying the oyster mat concept. These modules are sized based on pile diameter, and have an increased density of oyster shell attached. By wrapping dock pilings, substrate is able to be placed at an appropriate vertical elevation to meet the needs of any site specific location. Additionally, by keeping the substrate off the bottom, there is no risk of the benthic recruits being smothered by muck. Since the docks are already permitted structures, and no Submerged Aquatic Vegetation habitat is being used, no additional permitting is required. Studies on the design and feasibility started in 2013, and projects are ongoing. Observations have shown that after one year of immersion, typical communities growing on the modules include oysters, barnacles, sponges, algae, bryozoans, mussels, and tunicates. Each of the organisms provides an ecosystem service. Additionally, amongst the fouling shrimp, crabs, small fish, and amphipods have made a home. The project now in its 6th year is gaining popularity, and more communities are inquiring about how to get involved. Studies are examining the additional stresses on the pilings from the increased roughness, and quantifying the filtration efficiency for algae removal.
Presenter Bio: Dr. Weaver joined Florida Tech in August 2011 after working for three years as a post-doctoral research assistant at the University of North Carolina at Chapel Hill, Institute of Marine Sciences. He earned his M.S. and Ph.D. from the University of Florida in the Coastal and Oceanographic Engineering Program. He worked on coastal circulation projects including prediction of hurricane storm surge, tracking surface particles from the Deepwater Horizon Blowout, and 3D model development. In 2007 he founded a non-profit corporation whose mission is to encourage environmentally sound engineering, business and development practices. His areas of research and expertise include coastal flooding, coastal transport, living shorelines, water quality, 2D and 3D circulation modeling, and littoral processes.
Coastal Texas Protection and Restoration Feasibility Study – An Update
Kelly Burks-Copes, U.S. Army Corps of Engineers
Co Authors: Tony Williams
The Texas coast serves as a powerful economic engine for the nation by supporting several densely populated areas built around trillions of dollars of largely fixed public, private, and commercial investments. Unfortunately, Hurricanes Ike (2008) and Harvey (2017) clearly demonstrated the area’s vulnerability to coastal storm forcings (e.g., winds, waves, and surge). Given the current and projected sea level and climate change trends for the region, much of the built environment in the region could be rendered unsustainable. These communities now face tough choices as they contemplate adapting local land use patterns while striving to preserve community values and economic vitality. Absent improvements to critical infrastructure that adapt with changing future conditions, the next devastating storm event will likely result in similar or worse impacts. In 2014, the US Army Corps of Engineers in cooperation with the Texas General Land Office, kicked off a $19.8 million study to design potential protection and restoration solutions that would promote long-term resilience for the entire coast of Texas. In October 2019, the US Army Corps of Engineers and the Texas General Land Office jointly released a draft report detailing a comprehensive plan that contains both structural, non-structural, and nature-based solutions to provide both coastal storm risk reduction and ecosystem restoration for the coast of Texas. More than 6,000 comments were received on the plan, and the project delivery team (PDT) is now evaluating those comments and modifying the plan to improve benefits and reduce costs over the life of the project. Here we provide a status update on the study and describe changes to the plan since its release last year. Our path forward will be described, including the identification of a second public review period later next year.
Presenter Bio: Dr. Kelly Burks-Copes has over 27 years of experience working on both civil works and military projects for the U.S. Army Corps of Engineers specializing in hybridized engineering and environmental strategies to tackle coastal storm risk management, flood damage reduction, navigation, and ecosystem restoration problems across the country. She is currently the Project Manager on the Corps’ largest ever coastal storm risk management and ecosystem restoration study, commonly referred to as the Coastal TX study.
Coastal Texas Protection and Restoration Feasibility Study – Ecosystem Restoration
Tony Williams, Texas General Land Office
The U.S. Army Corps of Engineers (USACE) and the Texas General Land Office (GLO) are partners in the Coastal Texas Protection & Restoration Feasibility Study (Coastal Texas Study), a $19.8 million study to design potential protection and restoration solutions that would promote long-term resilience for the entire coast of Texas. The GLO and USACE have developed a draft comprehensive plan that includes storm surge risk reduction measures and large-scale ecosystem restoration project. The Tentatively Selected Plan (TSP) identified nine ecosystem restoration measures along the Texas coast. The projects were selected to restore and maintain 106,000 acres of habitat, and to maintain crucial geomorphological feature. The Coastal Texas Study was developed to work in concert with the GLO Texas Coastal Resiliency Master plan, that identifies 123 projects selected by coastal experts as best for enhancing coastal resiliency.
Presenter Bio: Senior Director of Planning
Texas General Land Office – Coastal Resources
A marine biologist with the Coastal Resources Program of the Texas General Land Office (GLO) where his primary responsibilities include the Coastal Texas Protection and Restoration Feasibility Study with the US Army Corps of Engineers (USACE), the Texas Coastal Resiliency Master Plan, working with USACE on other studies and regulatory issues, and derelict structure removal and disaster response. Prior to his current position he was the Director of the Coastal Resources Field Operation, and a biologist in both the Upper and Lower Coast Field Offices. Before coming to the GLO he worked in USACE Galveston District Regulatory and at the National Marine Fisheries Service where he worked on seagrass ecology research.
Wave Impacts from a Proposed Coastal Storm Risk Management Measure for the Galveston Bay Area
Margaret Owensby, USACE-ERDC-CHL
The U.S. Army Corps of Engineers Engineer Research and Development Center’s Coastal Storm Modeling System (CSTORM-MS) was applied along the Texas coast to study the impacts on storm surge and waves due to proposed coastal storm risk management measures. These proposed protection measures were comprised primarily of a system of levees and navigation gates along the Galveston Bay area of the open coast. Comparisons of storm surge impacts in the region have shown that storm characteristics including size, intensity, forward speed, and most notably, angle of approach have an appreciable influence on hydrodynamic processes and behavior in the Galveston Bay during a major storm event. However, an extensive examination of the impacts of these storm parameters on local nearshore waves has not been conducted heretofore. This talk will present an analysis of the effects of various storm characteristics on waves and wave properties for scenarios with and without proposed storm risk management structures. Wave height, period, and direction results for representative storm scenarios at a present day sea level will be shown and compared. This discussion will illustrate not only the inherent complexity of the storm protection system’s impacts on hydrodynamics in the Galveston Bay, but will also suggest that operational procedures for the protection system will be equally complex.
Presenter Bio: Ms. Margaret Owensby is a research hydraulic engineer with the U.S. Army Corps of Engineers at the Engineer Research and Development Center in Vicksburg, Mississippi. Since joining the Corps of Engineers in 2016, she has specialized in coastal modeling and data analysis, and has worked on a variety of projects to aid decision-making for both government and military agencies. She is a member of the Coastal and Hydraulics Laboratory’s Coastal Storm (CSTORM) Modeling System team, which uses a coupled numerical model to simulate both historical and hypothetical hurricane conditions in coastal regions.
Lessons Learned for Conducting Effective Public Outreach on Large Complex Corps Projects
Sharon Tirpak, U.S. Army Corps of Engineers
The Coastal Texas Protection and Restoration Feasibility Study is one of the larger studies within the Corps’ General Investigations portfolio. It is addressing both coastal storm risk management and ecosystem restoration concerns along the entire Texas Coast. Although the study is funded $20M and has a 5.5 year completion schedule, it has been a challenge to conduct the proper amount of public outreach on such a large, complex study. National Environmental Policy Act (NEPA) requires public scoping meetings and public meetings at the publication of the Draft Report and Environmental Impact Statement (EIS). This has proven inadequate to convey the complexity of the proposed solutions to the local communities, the natural resource agencies, and non-governmental organizations. In the era of social media, and with the intent to get the study’s messaging out to a broad swath of stakeholders, the team has developed a plan to communicate on multiple platforms. The project management team has been challenged to balance the need for outreach with significant budgetary and time constraints. Here we discuss some lessons learned from our efforts to implement a communications plan across a broad spectrum audience, and provide some insights into strategic communication opportunities.
Presenter Bio: Ms. Tirpak, originally from Pittsburgh, PA, attended college in southern Maine and graduated with a BS in Marine Biology. She began her career as a Fishery Biologist for the National Marine Fisheries Service conducting research on fish, dolphin and sea turtles. In 1994 Ms. Tirpak transferred to the U.S. Army Corps of Engineers, Galveston District where she worked in the Regulatory evaluating Department of Army Permits; in Planning developing feasibility studies; and since 2008 in Project Management leading multi-disciplinary teams through the planning, design and construction of federally funded civil works projects concerning flood risk management (inland and coastal storm), navigation and ecosystem restoration. She currently serves as a Deputy Chief of the Project Management Branch.
Coastal Barrier Resource Act Issues and Innovation in Florida
Aubree Hershorin, U.S. Army Corps of Engineers, Planning & Policy Division
Co Authors: Jackie Keiser
The U.S. Army Corps of Engineers, Jacksonville District (USACE), coordinates with the U.S. Fish and Wildlife Service (USFWS) prior to initiating work on Coastal Storm Risk Management projects located in Coastal Barrier Resource System (CBRS) units per the Coastal Barrier Resources Act (CBRA) of 1982. The Act meets its purposes in part through the restriction of Federal expenditures that have the effect of encouraging development of coastal barriers; however, the Act also stresses the consideration of means and measures by which the long-term conservation of fish, wildlife, and other natural resources may be achieved. For projects that create habitat for protected species, there is an argument that the project meets the purposes of Act and that Federal expenditures should not be restricted. The Jacksonville District works with USFWS to explain how our projects meet the purposes of the Act, and where they may not we may have the opportunity to coordinate with USFWS to adaptively manage our projects to meet the purposes of the ACT.
Regional sediment management (RSM) projects are a great example of working to meet the purposes of the Act. From an RSM perspective, laws and regulations in the coastal zone that affect sediment must take into consideration that coastal sediments are not static; they are constantly being moved and reworked through coastal processes. This is especially true for the areas surrounding inlets, where stabilization and adjacent development affects the sediment sharing system. An imbalanced sediment sharing system can negatively impact the resources that the Coastal Barrier Resources Act of 1982 (CBRA) was enacted to protect and RSM actions can counteract the imbalance and restore a shoreline to a more natural condition. Regional Sediment Management strives to utilize sediment that is already available in the system for restoring beaches, rather than obtain sediment from offshore sources that tend to be more expensive and less sustainable and are not affected by anthropogenic activities. RSM projects should, but are not always, looked upon favorably in terms of consistency with the CBRA Act. Implications of CBRA determinations in Florida will be presented.
Presenter Bio: Aubree Hershorin is an ecologist with the U.S. Army Corps of Engineers, Jacksonville District. She holds a bachelor’s degree in Environmental Policy from Franklin & Marshall College, and masters and doctoral degrees in Ecology from the University of Florida. Aubree has worked for USACE for ten years in the Planning Division, conducting NEPA analyses and ESA consultations for coastal storm risk management and navigation projects, and serving as the primary contact for sea turtle concerns related to coastal USACE projects in Florida. She conducted a six month detail with the U.S. Fish and Wildlife Service in 2012, gaining experience drafting biological opinions. Aubree is currently the lead planner for a Coastal Storm Risk Management Feasibility Study funded through the Bipartisan Budget Act of 2018, and is a subject matter expert with the National Center for RSM based at the Jacksonville District.
CBRA – Excluded
Patricia French-Pacitti, Workplace Management Inc
What happens when a Land Development Master Plan is a multi-site & multi-year oceanfront build out and was approved in 1980 prior to CBRA’s enactment in October 1982? CBRA Maps show the Island Dunes Community is surrounded by a CBRA boundary, with the encapsulated land marked “Excluded”. What exactly does “Excluded from CBRA” mean to Stakeholders living within this CBRA Exclusion?
Throughout a 20 year span, I proactively represented Island Dunes Stakeholders within their CBRA “Excluded” site. Constant challenges, ongoing research, hurdles & successes, faced by this presenter will be presented. Some are humorous; all stressful; and several are successful.
The presentation will focus on the north end of the S (St Lucie) County 2013 Project when it entered the Federal approval process. Due to CBRA, the Federal Mapping Phase Defining Project Boundaries for the S County project omitted Island Dunes. This Presentation will show how a community consisting of five high rise condominiums can be brought together. It was proven that Island Dunes is a worthy Federal partner and is included as part of the Final Project Boundaries Map.
Presenter Bio: Patricia French-Pacitti has idiosyncratically managed Florida oceanfront properties, condominiums, and large scale projects since the 1980’s. Given the Island Dunes CBRA history, and spurred on by Regency’s President, in 1999 I spearheaded formation of the Presidents’ Council first Beach & Dune Committee, which is still active to date. I excel at identifying situations and addressing same before they become problems.
Research (CBRA, SCC Act 2018) and growing a Coastal Management & Stakeholder Education are my Professional goals.
CBRA Zone Dredging for the Folly Beach Federal Nourishment Project
Spencer Wetmore, City of Folly Beach
Co Authors:[A previous presentation in this special session will provide background and history of the Coastal Barrier Resource Act (CBRA)].
This presentation will provide a site-specific example of the impact of CBRA legislation on federal shore protection projects, review the history of the Folly Beach CBRA zone exemption, and discuss challenges to use CBRA zone sand for future projects.
The City of Folly Beach is the local sponsor of the Folly Beach Federal Shore Protection Project (Project). A CBRA zone unit (Bird Key M-07) was established in the adjacent Folly River in 1990. Congress approved the Project in 1993 with the borrow area inside the CBRA zone. Therefore, this project has a congressionally-approved borrow area in a CBRA zone that was already in-place at the time of authorization. In 1990, U.S. Fish and Wildlife Service (USFWS) confirmed the shoreline stabilization exemption of CBRA was valid to allow dredging inside the CBRA zone.
This borrow area was utilized for the initial nourishment in 1993. However, the U.S. Army Corps of Engineers (USACE) refrained from using this borrow area between 1994 and 2018 because of a USFWS 1994 policy reversal that did not allow sand from the CRBA zone to be placed outside the CRBA zone. The cost of the alternate, offshore borrow area escalated and sediment quality deteriorated over the next two renourishment cycles.
In preparation for a 2018 Flood Control and Coastal Emergency renourishment project, USACE initiated consultation with USFWS to seek reinstatement of the exemption allowing the project to place sand from this authorized, affordable nearshore borrow area both inside and outside the CBRA zone. A portion of the sand was to be placed on the Bird Key Stono Seabird Sanctuary to benefit eastern brown pelicans and other threatened shorebirds. The alternate offshore borrow area would double project costs. The USACE suggested these uses were consistent with the purposes of CBRA and requested USFWS conduct an applicability determination of CBRA to this project.
In a letter dated July 28, 2017, USFWS stated that “The Service…believes that the Project is allowable under the CBRA” and provided a detailed “argument” to defend this determination. USFWS stated the following reasons to defend its decision to allow the project:
Like other federal and non-federal nourishment projects in the Southeast, it is unclear as to whether a similar determination will be provided for the next renourishment of Folly Beach.
Presenter Bio: Spencer Wetmore is the City Administrator for the City of Folly Beach, South Carolina. Prior to joining the City of Folly Beach, she was a prosecutor for the Charleston County Solicitor’s Office. She attended Princeton University for her undergraduate studies and Vanderbilt University for Law School. She lives on Folly Beach with her husband and two daughters.
Why the Feds can’t get sand from CBRS, but you can; and how this policy can change
Derek Brockbank, American Shore & Beach Preservation Association
Why can’t your federal beach project get sand from the constantly shoaling inlet right next to the beach? Because it’s in a CBRA zone.
The Coastal Barrier Resources Act (CBRA) was enacted in 1982 to prevent federal subsidies or expenditures on previously undeveloped barrier islands. The concept was incredibly sensible – don’t spend taxpayer money to develop land that is geologically dynamic and is particularly vulnerable to coastal hazards. Undeveloped barrier islands are also typically great habitat for wildlife and plants, and so mapping and regulation of the Coastal Barrier Resource System (CBRS) has been administered by the US Fish & Wildlife Service (USFWS). Significantly this law does not restrict development, it merely prevents federal funds from being used to support development.
CBRA has restricted National Flood Insurance Program (NFIP) eligibility and federal funding for public works projects in the CBRS. For the beach community, CBRA has meant properties in CBRS cannot be part of a federally authorized coastal risk reduction project. Additionally, USFWS determined CBRA establishes restrictions on federal expenditure for accessing sand resources in CBRS. This latter issue is where ASBPA has been getting involved.
For years, ASBPA has been arguing that accessing sand from within the CBRS to be used on a federal project outside the CBRS fell under CBRA’s statutory exemption of “nonstructural projects for shoreline stabilization that are designed to mimic, enhance or restore a natural shoreline.” However, time and again USFWS has rejected the argument based on a legal opinion that the exemption only applies to projects where both sand source and placement are within CBRS. This creates a bit of catch-22, since federally authorized coastal risk reduction projects cannot be authorized in CBRS.
We’ve tried pointing this out and made the additional rational argument for how accessing CBRS sand for a federal project can often be a) cheaper for the taxpayer (since the alternative may be off-shore or a more distant inlet), and b) better for wildlife since beaches create habitat. However, USFWS sees this as a legal issue based on how they interpret the law Congress wrote for them. So, ASBPA has begun to work with Congress to develop language that would address the issue of federal projects using sand from the CBRS at standard fed-local cost share.
This presentation will go into detail on a) the statutory CBRA exemptions that can allow for beach restoration; b) the history of the legal interpretation that prevents federal funding being used to access sand in CBRS; and finally, c) ASBPA’s policy recommendations to Congress that would allow federal beach projects to use CBRS sand at the standard cost-share while supporting wildlife resources.
Presenter Bio: As Executive Director of ASBPA, Derek Brockbank is responsible for the growth, strategic planning, and government affairs goals of the nation’s leading organization advocating for beach and coastal restoration. Previously, Derek worked as campaign director for a coalition effort to restore Coastal Louisiana, and was part of a gulf-wide campaign to pass the RESTORE Act. This followed up on work with National Wildlife Federation on climate adaption. Derek grew up in New York City and got his coastal education from an early age playing on the beaches of Long Island, and kayaking and fishing in Peconic Bay.
Sand Retaining Structure to Increase Longevity of Beach Nourishment – A Case Study in South Carolina
Haiqing Kaczkowski, Coastal Science & Engineering, Inc.
Defense against coastal erosion generally takes two forms – hard solutions involving shore-protection structures and soft solutions involving the manipulation of sediment supplies. An intermediate defense can also be implemented whereby hard solutions (such as groins, breakwaters, and jetties) are combined with soft solutions (such as beach nourishment) to achieve the most sustainable results.
Beach nourishment is the primary soft solution for coastal erosion and has been widely used in the United States. It rapidly preserves the recreational beach and protects upland in addition to other benefits including storm damage reduction and environmental enhancement. However, where a site’s erosion rates are high, or the length of the project is short, sand-retaining structures such as groins are sometimes incorporated to increase nourishment longevity.
The authors have combined groins and nourishment at several project sites in South Carolina to increase nourishment longevity. In this presentation, the Folly Beach County Park (FBCP) project will be used to quantitatively evaluate project performance and sustainability in relation to pre-project condition.
FBCP is situated along ~1,000 meters (m) of shoreline at the southwestern end of Folly Beach near Charleston, South Carolina. Nourishment in the form of navigation channel disposal and a 50-year federal shore protection project helped maintain the unstabilized spit at FBCP for many years. However, the lack of beach fills after 2005 resulted in dune line recession of over 120 ft in five years. The volumetric erosion rates between 2006 and 2012 ranged 25–30 cubic yards per foot (cy/ft) (downdrift and updrift reaches, respectively).
The technical study indicated that beach nourishment combined with a terminal groin was the optimal means of restoring and maintaining a recreational beach and protecting park infrastructure. The project was formulated based on the sand-trapping capacity of the groin, available funds, and the legal restrictions on groin construction in South Carolina. A crucial element of the groin design is the construction of three sections mimicking a natural beach profile: berm, sloping beach face, and low tide terrace. Nourishment sand totaling 415,000 cy and a 745-ft steel sheet pile groin with a concrete cap and armor stone toe protection were determined to be the optimal final design to achieve project objectives. Beach nourishment and groin construction was completed between May and June 2013.
The authors have been surveying the project area since project completion. The overall results show that the once eroding beach has become an accreting beach. Downdrift stations have gained an average of ~6 cy/ft/yr of sand between November 2013 and November 2018, indicating that the groin reached the maximum sand-trapping capacity and excess sand has bypassed the structure and migrated downdrift. Updrift stations have also gained sand at a rate of ~7 cy/ft/yr over the past five years. Adverse downdrift impacts of the structure have been negligible primarily due to a continued updrift sand supply and efficient bypassing around the low profile structure.
Presenter Bio: Dr. Kaczkowski has over 25 years of experience in coastal erosion assessment, beach restoration, and numerical modeling. She has used state-of-the-art numerical modeling tools in conjunction with engineering experience to design successful coastal development projects in North America, the Caribbean, the Middle East, and Asia. Dr. Kaczkowski currently serves as the principal engineer of Coastal Science & Engineering, Inc. (CSE), a consulting company based in Columbia (SC).
Myrtle Beach: A history of shore protection and beach restoration
Timothy Kana, COASTAL SCIENCE AND ENGINEERING
Co Authors: Tim Kana, Haiqing Kaczkowski
The City of Myrtle Beach (S.C.-U.S.A.) initiated a three-phase plan for beach restoration in the 1980s: Phase 1 – small-scale beach scraping; Phase 2 – medium-scale nourishment by trucks using inland sand; and Phase 3 – large-scale nourishment by dredge using offshore sand. Phases 1 and 2 were locally funded and served as interim measures (1981-1996) until a 50-year federal project could be constructed (1997 to present). In the course of this work, the City pioneered several approaches to beach management and became a model for the state. These include: the prototype S.C. beach survey program; the profile volume method for determining shorelines in the presence of seawalls, which was codified in the Beach Management Act (BMA) of 1988; the first locally funded nourishment (1986-1987) and FEMA-funded post-disaster renourishment after Hurricane Hugo – 1989-1990; and the first surveys of offshore deposits for nourishment. Before restoration, nearly 65% of the 9-mile (14.5 kilometer) oceanfront was armored with seawalls, bulkheads, and revetments (1981). After nourishment, erosion control structures are now buried and fronted by a vegetated storm berm, while a wider beach accommodates millions of visitors each year. Total volumes and adjusted costs of nourishment from 1986 to early 2018 are 4,997,201 cubic yards (3,820, 360 m^3) and ~$70.8 million ($2018) respectively. On a unit annual beach length basis, the cost of beach restoration and improvement has averaged $46.80 per one foot of shoreline per year (~$153.50/m/yr) ($2018). Oceanfront property values on a unit length of shoreline basis presently range from ~$15,000/ft (~$49,200/m) for single-family homes to ~$75,000/ft (~$250,000/m) for high-rise buildings, suggesting that beach maintenance has cost well under 0.5% of oceanfront property values per year. Sand loss rates have averaged ~0.8 cy/ft/yr (2.0 m^3/m/yr), and the rate of nourishment has been more than adequate to keep up with the ~0.37 ft (0.11 m) sea level rise between 1980 and 2018.
Presenter Bio: Dr. Kana is founder and president of Coastal Science & Engineering in Columbia (SC). He has 35 years of experience in coastal erosion projects and has written over 250 reports and publications relating to coastal processes, sediment budgets, beach nourishment, impacts of sea-level rise, and coastal zone management. He has been an advisor to the state of South Carolina on beach management issues since the 1980s and received research funds from the Army Corps of Engineers, EPA, NOAA, and other federal agencies. Kana and his firm have developed plans and supervised construction of 50 beach nourishment projects in South Carolina, North Carolina, Georgia, New York and the Caribbean totaling ~40 million cubic yards at a cost of ~$320 million.
He was awarded the 2015 Morrough P O’Brien Award of the American Shore & Beach Preservation Association, and CSE projects have received five Best Restored Beaches Awards from ASBPA since 2010.
A Tale of Two Nourishments: Initial Behavior of Subaerial Beaches Inside and Outside the Galveston, TX Seawall
Ben Ritt, Texas A&M University Galveston
Co Authors: Glenn Jones
In 2017 Galveston Island completed the 920,000 m3 of sand, 6.2 km long “Phase III Beach Nourishment: Seawall East” project along the “Historic Seawall” on the East end of Galveston Island, TX. This project was the largest sand placement in the state of Texas since the 1994 nourishment of the same area. In contrast the “2015 Phase II Beach Nourishment: Seawall West” project to create “Babe’s Beach” along the Galveston Seawall placed approximately 481,000 m3 of sand along a 2km stretch of seawall. These two projects differ not only in design but in the way the scope of the oceanographic forces and civil engineering related to the Seawall in those areas affect the nourishments. East of 61st Street the Seawall is broken up by a groin field and according to research by Texas A&M University Galveston (TAMUG) and the U.S. Army Corps of Engineers (USACE), net longshore transport moves West to East towards the Galveston/Houston Shipping Chanel. A small distance East from the 61st Street groin/fishing pier this long shore transport instead moves East to West along a section of the Seawall that does not have a groin field allowing for the transport of beach sand further west essentially stretching and thinning “Babe’s Beach”.
In June 2019 the Galveston Park Board in conjunction with the Texas General Land Office began a 2.5km long, 612,000 m3 of sand beach project to re-nourish and expand Babe’s Beach. Due to the recent 2017 nourishment of the “Historic Seawall” area and the monthly monitoring study conducted by the Texas A&M Galveston Campus to collect data on profile and volume change to the subaerial portions of that beach, the opportunity to conduct a similar study and intercomparison of the oceanographic forces and difference in engineering to the Seawall was completed. Data collected from the “Phase III Beach Nourishment: Seawall East” monitoring project was directly compared to the new “Babes Beach” monitoring project to determine if the previous studies by TAMUG and USACE in regards to net long shore transport matched what was documented in the subaerial sections of the new beach and to see the rate of transport and erosion of this new beach along a section of Seawall with no groins as compared to the section of Seawall where a groin field existed.
The data from 5 consecutive months of pre and post-nourishment subaerial survey were compared between the two projects to determine rates of erosion and accretion in the newly nourished beaches and a spreading rate for sand due to net long shore transport in the respective directions for each beach. Transport along the Seawall at “Babes Beach” moved laterally West whereas sand built-up at the inside eastern edge of the groins along the “Historic Seawall” beach. This data depicts the issues of forcing effecting change in beach nourishment projects on highly engineered coastlines.
Presenter Bio: Ben Ritt is a PhD student at Texas A&M Texas A&M University Galveston. He specializes in the use of remote sensing, UAS, and GIS techniques to study beach nourishment projects on the Texas coastline.
Optimization of Shore Protection Structures for Sargent Beach, TX
Michael Salisbury, Atkins North America, Inc.
Co Authors: Todd DeMunda, Rhonda Gregg-Hirsch
The Matagorda Peninsula and Sargent Beach have experienced some of the highest erosion rates along the Texas Gulf Coast. With evidence of shoreline retreat over much of the peninsula, the need for sand to stabilize and maintain critical reaches of shoreline is growing. Recognizing the importance and magnitude of this problem, the U.S. Army Corps of Engineers (USACE) completed a study in 2013 that evaluated structural methods to reduce beach erosion along Sargent Beach. The solution recommended by USACE was a set of 10 shore-parallel, segmented offshore breakwaters northeast of Mitchell’s Cut (within 7,200 linear feet of the inlet) with beach fill behind the breakwaters.
Leveraging the results of the USACE study, Matagorda County, in conjunction with the Texas General Land Office, is progressing with the design, engineering, and permitting of shore protection structures and a beach nourishment project along Sargent Beach. However, significant morphological changes have occurred since the USACE study was completed, necessitating an update and refinement to the numerical models that were used to evaluate the structural alternatives. Because of this, site-specific bathymetry and sediment data were collected in 2018 and used to update the numerical models applied in the USACE study. The modeling was also expanded to analyze more structural alternatives, including variations in structure types (offshore breakwaters and groins), structure size, orientation, and location.
Model results for each alternative were compared with focus given to the effectiveness of each structural solution in retaining sand on Sargent Beach, while also avoiding potential adverse impacts downdrift of Mitchell’s Cut. Noteworthy project findings include:
o Four segmented breakwater alternatives
o Four shore-perpendicular groin alternatives
o Three angled groin alternatives
o Three combined breakwaters and groins alternatives
o Breakwater structures are much more effective at reducing erosion and retaining sand on the beach than groin structures.
o An angled groin configuration is more effective than shore-perpendicular groins.
o Combination alternatives that combine elements from the breakwater configurations with an angled terminal groin at the inlet are the most effective solutions.
The final recommendation described above provides a comprehensive solution to the 7,200 linear foot beach segment immediately northeast of Mitchell’s Cut. The structural solution will reduce erosion and retain sand along the beach, which will lead to a more resilient coast and help prevent potential impacts to the Gulf Intracoastal Waterway (GIWW) due to breaching along the barrier island. This project is part of a long-term plan to stabilize and reduce erosion along the entirety of Sargent Beach.
Presenter Bio: Mike Salisbury is currently the Coastal Modeling Team Leader within the Atkins Technical Professional Organization, and has served as a project manager and technical lead supporting both public and private clients throughout the United States and abroad. Mr. Salisbury has 16 years of experience working on coastal-related projects including expertise in developing numerical models for flood risk assessment, floodplain mapping, long-term climatology studies, beach morphology analyses, and marine structure design. He has published several peer-reviewed articles detailing the development and validation of various coastal models and is Chair of the Coastal & Estuarine Hydroscience Committee for COPRI.
The Science (and Art) of Revetment Design
Chris Mack, AECOM
This presentation provides a review of a variety of revetment design considerations applied to several large-scale port and transportation projects. The presentation highlights the challenges of the design process infused with a mix of “rules of thumb”, empirical equations, and lessons learned. Concepts presented will highlight approaches recommended by USACE (CEM and SPM84), PIANC revetment design guids, EuroTop Manual, and CIRA (Rock Manual).
Presenter Bio: Chris Mack has over 28 years of coastal engineering and water resource experience in the public and private sectors. This includes more than 13 years with the US Army Corps of Engineers (USACE) and 15 years with private coastal and marine engineering firms. Chris has academic degrees in Water Resources, Coastal, and Software Engineering from NCSU, College of Charleston, and the Citadel. He currently manages AECOM’s Coastal Services and a staff of coastal engineers and CAD/GIS technicians for coastal projects on the east coast of the US including NC and SC.
The Sebastian Inlet District: Managing the Connection Between the Atlantic Ocean and Indian River Lagoon
Michael Jenkins, Applied Technology ad Management, Inc.
Co Authors: James Gray
The Sebastian Inlet District was established in 1919 by the Florida legislature and is currently celebrating its 100th anniversary (centenary). This presentation will provide an overview of the history and significance of Sebastian Inlet to the south-central Florida east coast region including initial attempts to create the inlet, formation of the District in 1919 and milestones in the inlet’s history to modern times. The District maintains an extensive collection of historical documents and exhibits related to the inlet and will draw upon this remarkable database to convey the unique history of the inlet and the region. The presentation will also address various aspects of current inlet management including channel maintenance, inlet bypassing and environmental resource management. The role of the inlet in maintaining water quality within the Indian River Lagoon will be discussed, in particular with respect to recent mass die-offs of seagrass within the lagoon system.
Presenter Bio: Dr. Michael Jenkins currently serves as Coastal Engineering Principal of Applied Technology and Management, In c. He has served as the engineer of record for a broad range of coastal engineering projects.
Over his career he has directed the placement of over 15 million cubic yards of cumulative nourishment volume through multiple nourishment efforts.
Subaerial Habitat and Bathymetric Changes Following Dredging of Little Egg Inlet, New Jersey
Kimberly McKenna, Stockton University Coastal Research Center
Co Authors: Alex Ferencz
In New Jersey Coasts and Rivers generally meet in backbay estuaries that are confined by the mainland to the west and the barrier islands to the east. Fresh water from rivers mix with ocean water and are driven by gravity and tidal forces to the Atlantic Ocean through tidal inlets, carrying sediment and depositing on the flood and ebb tidal deltas. In natural, unstructured inlets this constant inflow of sediments and longshore current leads to the creation of a series of highly dynamic inlet shoals. The combination of these sediment deposits and the importance of ocean access to the local economy causes a cyclical need of inlet maintenance, generally in the form of dredging.
A recent example in New Jersey is Little Egg Inlet (LEI), at the border between Ocean and Atlantic counties. LEI is one of two natural, unstructured inlets in the state and is surrounded by the Edwin B. Forsythe National Wildlife Refuge. Historically, the inlet had not been dredged, but an influx of sediment into the inlet system from an updrift beach nourishment project increasingly hindered navigation. In early 2018, the New Jersey Department of Environmental Protection (NJDEP) commenced dredging of the outer portion of the ebb tidal delta for the purpose of utilizing the sand to address erosion and maintenance of the shore protection project on southern Long Beach Island. The Stockton University Coastal Research Center (CRC) in partnership with the NJDEP began a topographic/bathymetric monitoring program to determine changes in the dredged channel as well as to the beaches of the Forsythe National Wildlife Refuge (Holgate Unit and Little Beach Island Unit). Monitoring was accomplished using a combination of boat-mounted single beam echo sounder, terrestrial LiDAR systems, and traditional beach profiling.
The Holgate Unit is located immediately downdrift of the beach fill, and prior to nourishment had experienced long-term shoreline erosion. The Little Beach Unit is the only natural, uninhabited barrier island along the New Jersey coast and has experienced major morphological changes. LiDAR generated classified point clouds were used to create Digital Terrain Models (DTMs) and Digital Elevation Models (DEMs) of the subaerial habitats and compared to datasets obtained in 2016. In addition, these models were combined with the 2018 topographic and bathymetric datasets to identify geomorphic fluctuations and determine changes in elevations, volumes, and shoreline position from previous studies of the area.
Study results indicate elongation of the Holgate spit into the Little Egg Inlet channel as a result of erosion of the beaches in the northern portions of the Unit. On Little Beach Island, erosion of the northeast facing shoreline contributed to accretion on the southeast facing shoreline. Other areas of notable change were deepening and erosion within the existing Little Egg Inlet main channel and accretion on the adjacent north side.
The study will continue through 2019 to provide NJDEP an assessment of dredging performance and impacts to the surrounding shoal system and shorelines.
Presenter Bio: Kimberly McKenna is the Director of Sponsored Programs and Senior Project Manager at the Stockton University Coastal Research Center with over 25 years’ experience working in coastal processes research and shoreline management. Ms. McKenna is a registered professional geologist (DE & TX), receiving a Master of Science degree in Geology at the University of South Florida. She has authored several publications including those used as the scientific basis in the development of state legislation, rules, and funding programs as well as peer-reviewed articles and reports regarding coastal processes, shoreline changes, sand sources, and regional sediment management.
INLET MANAGEMENT STRATEGIES WITH CASE STUDIES FROM FLORIDA
Thomas Pierro, Coastal Protection Engineering
Co Authors: Michelle Pfeiffer, João Dobrochinski, Morjana Signorin
It has long been known that inlets modified by the works of man can hold large quantities of high-quality sand with impacts that can be long term and significant. This presentation will provide an overview of inlet related erosion in Florida with examples of management strategies formed on the basis of state policy, traditional coastal engineering practices, and advanced numerical modeling as it relates to the future sustainability of coastlines in the presence of tidal inlets.
There are 825 miles of sandy beaches in the state of Florida, of which 525 miles (63.6%) are eroding and 429.6 miles (52.1%) are deemed critically eroded (FDEP 2018). Florida also has 66 tidal inlets at present, which fluctuates due to the dynamic nature of the coast and the complex tidal systems. In a typical coastal system, tidal currents and wave action suspend and drive sediment along the beach by longshore transport. Upon encountering an inlet, the sediment can become entrained in the tidal flow and deposited in the inlet’s ebb and flood shoals. Since inlets are constantly seeking a state of equilibrium, the shoals continue to grow in size at the expense of the adjacent beaches until sand bypassed to the downdrift side is equal to the sand entering from the updrift side. In cases where inlets have been modified by the works of man and the longshore drift is pronounced, there is a disruption to the equilibrium resulting in accretion on the updrift side of the inlet and erosion on the downdrift side.
A critical component for inlet management is balancing the sediment budget. This evaluation of the littoral flow of sand is based on survey data and nourishment records with the objective of quantifying the impact of inlet, estimating bypassing quantities, and identifying the needs to balance the budget. In contemporary inlet management studies, the sediment budget also serves as the base to calibrate numerical models, which can be used to test a wide array of management alternatives. There are several different management strategies that have been implemented around the State of Florida, many of which involve a combination of techniques. Examples to be presented include South Lake Worth (Boynton) Inlet and Boca Raton Inlet, which both have established bypassing systems. Modern inlet management studies often employ advanced numerical modeling techniques to aid in the evaluation of alternative strategies. Recent case studies to be presented include the following:
Longboat Pass Inlet Management Study – Delft3D numerical modeling study used to examine the sediment transport patterns near the inlet and evaluate various structural and dredging scenarios.
Blind Pass Inlet Management Study – Study to assess the coastal processes and evaluate strategies of maintaining an open inlet through Deft3D numerical modeling of the inlet and adjacent beaches.
Redfish Pass Inlet Management Study – Delft3D numerical modeling analysis to evaluate the ebb shoal for bypassing and analyze the potential impacts to the coastal system.
Presenter Bio: Tom Pierro is Principal Engineer of Coastal Protection Engineering, managing projects, business development, proposals, and financial oversight as a Managing Member of the firm. Mr. Pierro also has broad experience in project management, planning, design and permitting, engineering and modeling, plans and specifications, field investigation, construction oversight, and feasibility studies of coastal engineering projects. Over the last 18 years, Mr. Pierro has worked on many shore protection, beach nourishment, and marine structure projects around the nation and abroad.
Improved Design of Roads along Beaches
Scott Douglass, South Coast Engineers
Co Authors: Bret Webb, Brian Beucler, Joe Krolak
Coastal roads impact our beaches and shorelines in many ways… some not so good. We all drive to the beach on public roads but, the roadway can affect the shoreline itself. The planning and design of coastal roads and bridges is important for many habitat and quality of life reasons.
The Federal Highway Administration’s (FHWA) primary reference manual for highways along the US coast has been revised in fall 2019 to better incorporate principles of coastal resilience and nature-based solutions.
FHWA’s Hydraulic Engineering Circular No. 25 (3rd edition) “Highways in the Coastal Environment,” is used by State and local Department of Transportation professionals in planning, designing, and operating roads near the coast that are always, or occasionally during storms, influenced by coastal tides and waves. The manual is written to be understood by a wide cross-section of users with varying backgrounds and expertise. It summarizes the broad field of coastal science and engineering including tools for estimating water levels, waves, and sand movement; discusses the typical problems faced by coastal roads; and recommends solutions.
This presentation will focus on the revised manual’s new recommendations for improved resilience. This includes a specific recommendation for future sea level rise that should be included in design decisions, methods for quantifying increased flooding due to relative sea level rise (“nuisance flooding”), how to include sea level rise in coastal storm vulnerability assessments in every coastal region of the US, and techniques to improve resilience of coastal roads. Nature-based solutions including beach nourishment and living shorelines are highlighted.
The revised manual is scheduled to be released in early October 2019… just in time for the ASBPA conference.
Presenter Bio: Scott Douglass has visited almost every beach in this country and wrote the book “Saving America’s Beaches: The causes of and solutions to beach erosion.” He is the founder of South Coast Engineers, a coastal engineering consulting firm in Fairhope, Alabama and an Emeritus Professor of Civil Engineering at the University of South Alabama with over 35 years of experience in beach erosion solutions, living shoreline designs, and engineering of our nation’s coastal highways. He serves on the ASBPA Board of Directors.
Building Back Better – FEMA’s Public Assistance 406 Hazard Mitigation Funding
Janan Evans-Wilent, Federal Emergency Management Agency
Co Authors: Samuel Capasso
Coastal storms and flooding pose significant risk to coastal communities and may cause substantial property and infrastructure damage. For example, according to the National Oceanic and Atmospheric Administration (NOAA), the three largest hurricanes during the 2017 Atlantic hurricane season caused an estimated $265 billion in damage in the US. The Federal Emergency Management Agency (FEMA) is the primary federal agency for funding assistance after such disasters. FEMA’s Public Assistance (PA) program is FEMA’s largest grant program used to repair and rebuild community infrastructure damaged by a federally declared incident. While disasters wreak havoc on communities and their residents, FEMA provides PA funding to help communities not just rebuild to pre-disaster conditions but to build back better.
PA 406 Hazard Mitigation is funding for cost-effective hazard mitigation measures for any eligible facilities damaged by the incident. This funding source has been historically underutilized in most disasters, with more mitigation spending occurring under Hazard Mitigation Grant Programs (HMGP) which have limited funding and are only available through an annual state-led competitive grant process. PA 406 hazard mitigation funding is available for any eligible PA permanent work project and has significant potential to provide necessary funding for many large-scale mitigation projects, particularly for vulnerable critical infrastructure in coastal areas and floodplains. Although funding is available for states, local governments, tribal governments, and territories, there has been a shortage of clear and accessible information about 406 mitigation policies and requirements. In this presentation, the new 406 hazard mitigation-focused Community Infrastructure Branch will describe the opportunity for 406 hazard mitigation funding under the PA Program, detail how coastal practitioners can utilize these funds and incorporate long-term mitigation planning into post-disaster response, clarify common misconceptions about PA 406 hazard mitigation, and showcase coastal infrastructure case studies that leverage PA 406 hazard mitigation funding to support resilient communities.
Presenter Bio: Janan Evans-Wilent is a member of the new Community Infrastructure Resilience Branch at FEMA Headquarters, focused on Public Assistance 406 Hazard Mitigation. Janan is a former Knauss Sea Grant Fellow with a Master’s in Coastal Hazards and Adaptation from Oregon State University.
An Introduction to the Undersea Cable Industry
Robert Wargo, North American Submarine Cable Association
The presentation will provide a brief overview of the undersea telecommunications cable industry, our history, the importance of undersea cables and ensuring their uninterrupted operation, methods of installation, maintenance and protection, facilities locations throughout the US, the need to avoid damage to cables and the consequences of damaging them.
Presenter Bio: Bob Wargo has 28 years of experience in the undersea cable industry at AT&T, is the current president of the North American Submarine Cable Association and former Chairman of the International Cable Protection Committee.
Coastal highway vulnerability along a barrier island
Elizabeth Sciaudone, North Carolina State University
Co Authors: Liliana Velasquez Montoya, Elizabeth Smyre, Margery Overton
Coastal highways are vulnerable to changes in landscape that occur at variable scales in time and space. In particular, highways along barrier islands suffer the consequences of the combined action of the ocean, the back barrier lagoon, and the morphological changes of the island. Thus, long-term and large-scale programs to monitor and assess vulnerability of roads along barrier islands are critical for their sustainable management and operability. An example of such a program is the Coastal Monitoring Program for the NC 12 Highway along Hatteras Island, NC, USA. This unique monitoring effort that has been in place since 2011 extends 13 miles along a barrier island. Within this program, bimonthly aerial images and quarterly photogrammetrically-derived digital terrain models are used to digitize ocean and estuarine shorelines, roadway location, and dune elevations. Based on these data and historical damage patterns, three vulnerability indicators were defined along shore-normal transects: 1) Island width < 1000 ft, 2) Dune crest elevation < 10 ft above the highway, and 3) Edge of pavement within 230 ft of the ocean shoreline. In addition, vulnerable areas of the coastal highway (by 2030) have been predicted from historical records of shoreline positions (mid-1940s to present) since 2013. A compilation of the results from 2011 to 2018 indicates that there is a single 5 km-long stretch of the road that is not vulnerable along the study area. The other 16 km of the highway have met at least one vulnerability criterion since 2011. A composite of vulnerability and shoreline predictions reveals five main regions of concern; of those regions, two breached during Hurricane Irene in 2011 and the others have suffered major dune erosion, overwash, and flooding during Hurricane Sandy in 2012 and subsequent nor’easters. The vulnerability assessment which will be presented in this talk continues to inform the state Department of Transportation on planning and adaption strategies for future phases of highway improvements.
Presenter Bio: Beth Sciaudone received her B.S.E. in civil engineering from Duke University and her master’s degree and Ph.D. in civil/coastal engineering from North Carolina State University. She has worked for a state agency and as a consulting engineer. She currently works as a research assistant professor at NC State. She is a licensed P.E. in the state of Florida.
Resilience in action: Connecting engineers, nature, and communities
Danielle Boudreau, GHD
Co Authors: Brian Leslie
Nature-based solutions provide communities an opportunity to reduce coastal flooding and erosion, while simultaneously maximizing ecological and sociological benefits. To-date there have been numerous assessments and planning efforts working to increase coastal resilience but there is a need to better understand how these efforts directly translate to actions on the ground. How do we integrate the best-available interdisciplinary science into meaningful projects? How can engineers work with environmental and social scientists to design more comprehensive coastal resilience solutions? This presentation will explore how engineers can work with nature and communities to prepare for changing climatic and coastal conditions. Case studies from California will focus on lessons learned and identify opportunities to overcome challenges experienced through creative partnerships with scientists, planners, and resource managers. The audience will be introduced to innovative approaches for implementing and monitoring living shorelines to demonstrate tangible increases in coastal resilience.
Presenter Bio: Dani Boudreau is the Senior Resilience Specialist for GHD’s Coastal & Maritime group, where she is catalyzing strategic partnerships between nonprofits, academia, governments, and the private sector to implement innovative adaptation strategies. Specifically, Dani is leading interdisciplinary collaborations linking resilience planning to multi-beneficial projects that advance nature-based solutions. Her work has lead to cutting-edge approaches to integrating evolving climate science into actionable coastal management decisions. Previously she worked for NOAA’s Tijuana River National Estuarine Research Reserve, where she founded and led the Resilience Initiative to link leaders, scientists, and communities to the best-available adaptation planning tools and management practices.
CZF Abstract – Shoreline Stabilization to Liven up the Banks of New York
Erin Hague, Tetra Tech, Inc.
Co Authors: Richard Czlapinski, Bret Bienkowski
The Mill River watershed, located in southwest Nassau County, is a microcosm of New York’s Long Island. Although urbanized and developed along most of its banks, the Mill River supports a variety of wildlife and serves as a water access point for residents and visitors. In response to the devastation of Hurricane Sandy, the US Department of Housing and Urban Development’s (HUD’s) Rebuild by Design program awarded funding to New York State through the Living with the Bay (LwtB) proposal, which promoted a watershed approach to protect and enhance this diverse area. The Mill River Living Shoreline project is one of 34 projects in the $125 million LwtB program.
The Living Shoreline project extends for approximately 3,550 feet of river bank along two segments of publicly-owned shorelines. Frequently-occurring flood events have resulted in significant bank erosion with associated loss of wetland and upland habitat areas and public water access opportunities. Limited response efforts involved dumping of concrete debris along the shoreline, further degrading the ecological value of the river’s shoreline.
The project is applying living shoreline principles, to protect and enhance the river banks. The stabilization design combines natural habitat and man-made structural features that seeks to increase the resilience and reduce the erosion vulnerability of the river’s banks. The living shoreline project is designed to mesh with related LwtB project components involving the development of greenways to improve public access and viewing opportunities of the riverway, as well as stormwater and flood protection.
The project field work involved a bathymetric survey of the river bottom, a LiDAR survey of the river banks, a wetland delineation survey, and a geotechnical sampling and laboratory analysis program. The design work includes wave and current modeling, design of structural elements, and the planning and design of natural habitat components of the projects.
Tetra Tech is responsible for the development of the design concept, field investigations, engineering and design, regulatory coordination and permitting, preparation of construction documents and cost estimates and support services during the bidding and construction of the project.
Presenter Bio: Ms. Hague is Director of Tetra Tech’s Center of Coastal Services in Southeast Florida and is a Certified Environmental Professional with more than 24 years of experience specializing in shoreline protection and coastal restoration projects. Ms. Hague is proficient in managing multi-disciplinary projects involving geotechnical and biological field investigations, agency coordination and permitting, and coastal planning and engineering design. Ms. Hague specializes in coastal and marine development, ecological restoration, and living shoreline projects.
Coastal Design and Construction of New Jersey Multipart Living Shoreline
Travis Merritts, Anchor QEA LLC
Co Authors: Ram Mohan, Matt Henderson, Steven Bagnull
Coastal design of large-scale living shorelines requires careful modeling and evaluation of forces over the full length of a proposed system and may require a design that integrates multiple technologies and construction approaches changing coastal conditions. We will discuss the planning, engineering, and construction of 4,150 ft long living shoreline to stabilize an eroding island shoreline in the back bay of Ocean City, New Jersey. Due to the variable coastal forces acting on the proposed living shoreline alignment, multiple protection techniques and materials were integrated in the final design. The recently completed living shoreline was designed and constructed as part of a Hurricane Sandy National Fish and Wildlife Foundation recovery grant and consisted of a 2,700 ft rock sill and a 1,450 ft oyster habitat block reef. The different living shoreline technologies corresponded to variations in wind wave conditions, vessel wake, ice impacts, historical erosion patterns, and water depths. A hydrodynamic model of Great Egg Harbor Bay was developed to evaluate erosive forces acting across the living shoreline under various storm event simulations and under typical conditions. We will examine lessons learned during construction of the living shoreline which was completed in April 2019 and discuss long-term monitoring of the living shoreline.
Presenter Bio: Travis Merritts is a Managing Engineer for Anchor QEA working out Philadelphia, Pennsylvania. He has over 13 years of experience working on wetland, coastal, dredging, sediment management, and sediment remediation projects located throughout the country. Mr. Merritts has been closely involved with management of the back bay system in Ocean City, New Jersey for the past 4 years.
Alabama Swift Tract Living Shoreline Monitoring: Results and Lessons Learned
Sina Amini, HDR
Co Authors: Sina Amini, Daniel Van-Nostrand, Estelle Wilson
The Alabama Swift Tract Living Shoreline Project consists of 21 low-crested breakwaters in eastern Bon Secour Bay, Alabama within the Weeks Bay National Estuarine Research Reserve. The National Oceanographic and Atmospheric Administration (NOAA) implemented the project to offset injuries to natural resources caused by the 2010 BP-Deepwater Horizon oil spill.
When construction was completed in early 2017, the NOAA Restoration Center initiated a 7-year post-construction monitoring program to determine if the project goals are being met. The 3 main project goals were to build living breakwaters, support habitat utilization, and reduce shoreline erosion rates. The project monitoring plan established quantitative objectives including measurements of fauna and bivalves density, topographic and bathymetric surveying of the breakwaters and the shoreline, and analysis based on visual observations.
After 2 years of post-construction monitoring, the project is already showing unexpected results. Large amounts of sediment have deposited on the landward toe of the breakwater and many portions of the shoreline have accreted. While the accretion is causing the project to exceed performance goals related to shoreline location and shape, several cages used for biological sampling have partially filled with sediment. Despite the large accretion, the project is still meeting biological performance goals for bivalve and epifauna sampling.
The Project’s performance will continue to be monitored for the full 7-year period to determine if the sediment deposition has stabilized, if accretion will continue, or if the accreted sediment will consolidate. Results of this analysis can be used for future projects to better establish project and monitoring goals. The presentation with include a review of the post-construction monitoring results and a discussion of these unexpected issues and related solutions.
Presenter Bio: Sina Amini is a professional engineer with over 5 years of experience in coastal and hydraulic engineering. He currently serves as Coastal Engineer and Assistant Project Manager at HDR, Inc. Sina has worked on a variety of coastal engineering projects such as feasibility studies, revetment design, waterway dredging, shoreline protection, and metocean studies. His field of expertise include data analysis, numerical modeling, and application of high level programming languages to streamline coastal and water resources engineering tasks.
Edgartown Vulnerability Preparedness and Climate Change Assessment
Tara Marden, Woods Hole Group
Co Authors: Tara Marden, Joe Famely
Edgartown is surrounded by the Sea and susceptible on every level to the wraths of coastal storms and sea level rise. Edgartown is an urban center with dense development and is highly populated when compared to other parts of the Martha’s Vineyard. The downtown has lots of paved surfaces, hard structures such as bulkheads and seawalls, causeways and buildings and many of the roads and utilities are vulnerable to storm damage, flooding and sea level rise.
Surrounding the Harbor, Edgartown has numerous critical facilities just feet above sea level including the Chappy Ferry Terminal, Harbor Master’s Office and the Dock Street Wastewater Sewer Station, all within the Velocity Zone and highly vulnerable during even a Category 1 Hurricane. Edgartown also has many critical facilities located within hurricane surge pathways, including Edgartown Police Station, Emergency Operations Center, Walk-In Medical Facility, Lily Pond Well, Harbor Master’s Office, Dock St Sewer Station and the Town’s Wastewater Infrastructure Facility. Potential damage to these facilities is becoming more and more of a concern with the increase in frequency and magnitude of coastal storms.
Despite the fact that Edgartown has been working tirelessly to enhance the resiliency of the many miles of coastline to protect private and public infrastructure, the Town faces multiple challenges related to the impacts of natural hazards, which are felt differently across the Town in the low-lying coastal areas, forested uplands and developed downtown area. The northern and eastern shores of Edgartown are surrounded by Nantucket Sound, while the southern coast of Edgartown is exposed to the Atlantic Ocean. This geographic setting exposes low-lying areas to damage from coastal flooding, coastal erosion and storm surge. The forested inland areas experience the effects of tree damage from wind, snow and ice, and inland flooding along roads due to poor drainage. Surrounding the Harbor, the vulnerability of the Town’s low-lying coastal roads, bridges, and boat landings to flooding is concerning. Flooding, whether caused by coastal storm surge or excessive rainfall, presents a major threat to the Town’s infrastructure, facilities, neighborhoods and emergency preparedness and response and requires comprehensive and tailored actions for establishing mitigation priorities for different areas of Town.
To address these concerns, the Town is conducting a detailed climate change vulnerability assessment of municipal assets and natural resources to prioritize and develop targeted adaptive strategies aimed at reducing risks from flooding, increased storm intensity, sea level rise and storm surge. The goal of the project is to develop a GIS database the Town can use moving forward with resiliency planning, to provide data on likely scenarios and degrees of potential impact in vulnerable areas, and to assist in the development of recommended strategies to minimize risks to infrastructural, societal and environmental features. A range of climate change adaptation measures are being considered including site specific measures that protect single properties, shoreline measures (including nature-based solutions) that protect multiple properties, and policy/regulation measures that enhance existing town-wide protection standards. The results of the study, which will incorporate outreach and education, will be presented.
Presenter Bio: Marden has 22 years of experience in the areas of coastal geology and coastal process evaluation. During her tenure at Woods Hole Group, Ms. Marden has specialized in many projects related to managing and implementing regional dredging and beach nourishment programs for local municipalities and private homeowners tidal inlet and sediment transport processes, sand resource investigations for beach nourishment as well as design, permitting (local, state, and federal) and construction oversight for a myriad of coastal structure and bio-engineered projects. She is experienced with all facets of environmental impact analyses, ranging from the collection of field data to engineering design, alternatives analyses, and design for mitigation.
Living on the Edge: Developing a Property Owner’s Guide to Promote Holistic Management of Coastal Bluffs
Lydia Salus, University of Wisconsin – Madison Sea Grant Institute
Co Authors: Adam Bechle, Gene Clark, Julia Noordyk
Coastal bluffs are a unique place to live because of the dynamic coastal processes that shape them. The coastal bluffs on Lake Michigan in Southeastern Wisconsin are vulnerable to coastal hazards including erosion, coastal storms, fluctuating water levels, and ultimately bluff failure. In order to build resiliency in Wisconsin’s Lake Michigan coastal communities, a “Property Owner’s Guide to Protecting Your Bluff” is being developed to provide property owners with usable information that helps them look at the top, face, and toe of their bluff to determine if they have a problem, understand the underlying cause of the issue, and think through available management practices. Because of the variability of Lake Michigan’s shorelines from one county, city, or property to the next, there is no “one-size-fits-all” solution to bluff erosion; therefore, this guide is written so property owners understand the problems facing their property before reacting with a solution to ensure that the right problem is being addressed. Moreover, the guide encourages holistic bluff management by controlling groundwater and surface water, protecting the slope face against surface erosion, and defending the bluff toe from wave action if necessary. Use of nature-based features are promoted in an appendix focused on the selection of appropriate vegetation for enhancing bluff and shoreline stabilization which includes a description of 45 regionally native plants appropriate for this purpose. This guide is being produced as part of a larger regional effort to enhance the capacity of coastal communities and residents to plan, prepare for and adapt to coastal hazards. As part of this larger project, the “Property Owner’s Guide to Protecting Your Bluff” will be disseminated to its intended audience of private property owners in partnership with the local, coastal governments and the regional planning commission. The expected outcome of this outreach publication is reduced property damages from coastal bluff erosion by providing a framework for property owners to identify and prioritize vulnerabilities on their bluffs with appropriate risk-reduction practices.
Presenter Bio: Lydia Salus is a Water Resources Management Master’s student at the University of Wisconsin – Madison. She earned her Bachelor of Science in Environmental Sciences, Policy and Management from the University of Minnesota – Twin Cities. After completing her undergraduate degree, she worked on an ecological restoration field crew in Southeast Wisconsin implementing management solutions for bluff and slope stabilization and erosion control around Lake Michigan. These management projects included slope reconstruction, establishing native vegetation, and managing surface water runoff. Beyond environmental restoration and water management, her professional interests include working in the field, communicating science, and putting ideas into action.
A New Way of Looking at Sea Level Rise Vulnerability of Transportation Infrastructure
Christopher Webb, Moffatt & Nichol
Co Authors: Sarah Richmond, Sarah Pierce, Kimberly Dotson
The San Diego Association of Governments (SANDAG) is analyzing vulnerability of regional transportation corridors to sea level rise (SLR) in San Diego County. A standard engineering technical vulnerability assessment (VA) was done and then expanded upon with a risk assessment. The risk assessment is a new lay-friendly tool developed for non-technical users. The new risk assessment adds more context to the VA results. The approach considers scenarios of existing sea level conditions and SLR of 2.5 feet and 6.6 feet above existing conditions, as well as no storm and 100-year storm conditions. The CoSMoS model developed by the U.S. Geological Survey was used for flooding and inundation estimates.
The standard engineering technical approach evaluated regional transportation corridors selected by key stakeholders and decision-makers. Those corridors included three roadways, eight pedestrian/bike trails, and 4 transit lines (railroad and trolleys). Results showed multiple bridges and roadway segments vulnerable to flooding under existing conditions, and for both SLR and storm scenarios. Adaptation measures consist of raising roads and bridges in the future, installing living shorelines, retreating, flood-proofing, and other measures.
The new supplemental risk assessment was done using a tool called the Vulnerability Assessment Scoring Tool (VAST) developed by the U.S. Department of Transportation Federal Highway Administration. SANDAG conducted this pilot study with VAST to determine its suitability to analyze SLR impacts to transportation. VAST is geared toward the layperson to evaluate potential vulnerabilities of public transportation routes. Two roadways, two transit routes, and two bikeways/trails analyzed in the first approach were assessed in this second approach. The VAST process quantifies asset vulnerability on a scale of 1 to 4 (low to high) based on exposure, sensitivity, and adaptive capacity.
VAST results showed two highways with the highest vulnerability, followed by the railroad, trolleys, and trails. The VAST tool was found to be effective, especially through its prompted vulnerability indicators and organized method of documentation. Results were objective but could be modified by a weighting scale assigned by the evaluator. This study’s conclusions indicated that location of an asset between the ocean and upland development dictates vulnerability. Also, the most vulnerable roads are those that provide access to critical facilities such as hospitals, police stations, city halls, naval infrastructure, and other vital public assets.
Adaptation best practices were developed to improve resilience. These practices included collaboration between municipalities, public outreach and information sharing, preparing detailed VAs, developing adaptation policies, practicing multi-jurisdictional planning through the regional coordinating agency of SANDAG, and developing an adaptation toolbox (policies, actions, and funding). The draft study is ongoing and is scheduled to be finalized in late 2019.
Presenter Bio: Chris Webb is a Supervisory Coastal Scientist at Moffatt & Nichol in Orange County, California where he has been with the company for 27 years. Mr. Webb manages beach, wetland, and estuarine restoration projects in Southern and Central California. His work includes planning, and concept and final engineering designs of tidal wetland restoration projects, beach nourishment projects, and freshwater marsh restoration. Mr. Webb received Bachelor and Master of Arts degrees in Geography from San Diego State University.
Adaptation Planning for a More Resilient Coastline
Angela Schedel, Taylor Engineering
Co Authors: Jenna Phillips
The objective of this presentation is to illustrate the methodology and development of a practical, concise and strategic adaptation plan with a list of action steps which can be implemented to adapt to climate change, with a focus on coastal flood protection. The first part of this adaptation plan is a vulnerability analysis incorporating best available sea level rise projections and FEMA Stillwater surge depths for the City of Punta Gorda, Florida. In order to conduct a ‘best practices’ vulnerability assessment with average annual loss estimations to structures and contents, the following data was researched: a) building location, b) finished floor elevations (FFE), c) lowest adjacent grade elevations (LAG), d) replacement value, e) contents value, f) year built, and g) type of construction. A GIS-based study was used to identify the coastal flooding exposure of critical facilities and historic properties within the City.
The GIS-based vulnerability analysis compares the elevation of various inundation scenarios using both a simple bathtub model and a modified bathtub model. The simple bathtub model identifies all areas under a target elevation as potentially flooded, regardless of hydrologic connectivity. The modified bathtub model applies a hydrologic connectivity filter to remove isolated inundated areas not connected to a major waterway. The City’s stormwater infrastructure GIS layer was used to inform these hydrologic connections. The NOAA Mean Higher High Water (MHHW) elevation is used to simulate nuisance flooding, with 1.5 foot and 3 foot sea level rise scenarios simulating medium and high inundation scenarios. The 25 year, 100 year, and 500 year FEMA tropical surge Stillwater elevations were also used to inform the city’s flood exposure to extreme events. The exposure analysis identified a variety of vulnerable focus areas, for which adaptation strategies were recommended. For each adaptation strategy, the plan provides guidance on implementation over short, intermediate, and long-term timelines.
This adaptation planning effort updates the City’s 2009 climate adaptation plan and recommends changes to the City’s Comprehensive Plan to comply with the Florida “Peril of Flood” statute. The City also requested a Living Shoreline Technical Guidance document in order to promote this resilient adaptation option. The Living Shoreline focus area will also be presented as one of the recommended adaptation strategies.
Presenter Bio: Angela Schedel is the Director of Community Resilience at Taylor Engineering in Jacksonville. She is a career Naval Officer, having served 25 years as a helicopter pilot and an engineering professor. She has a Bachelor’s in Ocean Engineering from the U.S. Naval Academy and a Master’s and PhD in Civil Engineering from the University of Maryland. Her research, including her dissertation entitled “Sea-Level Rise and its Economic Effects on Naval Installations,” has earned her recognition as a subject matter leader in sea level rise and adaptation solutions. She enjoys spending time in, under and on the water.
USACE National Regional Sediment Management Program: A Look Back and into the Future
Katherine Brutsche, USACE ERDC
The US Army Corps of Engineers National Regional Sediment Management Program is celebrating its 20th anniversary this year. This presentation will take a look back at the beginnings of the program and how it came to be, as well as discuss current topics important to the program and a look into the future. Current topics will include ongoing research, updates on 1122, and other important issues. A summary of future goals of the program as it relates to increased beneficial use of dredged material, more efficient management of projects, and other topics important to the ASBPA will be given.
Presenter Bio: Dr. Katherine Brutsché is a Research Physical Scientist at the USACE Engineer Research and Development Center in Vicksburg, M.S. She received her Masters and Ph.D. at the University of South Florida in 2011 and 2014, respectively. Her Bachelor of Science degree in Geosciences was completed at Virginia Tech in 2007. Her dissertation research focused on the sediment characteristics and morphological impacts of the nearshore placement of dredged material in Fort Myers Beach, Florida and Perdido Key, Florida. Currently, she is continuing her research on nearshore berms and is the Program Manager for the Regional Sediment Management Program.
Simulation of Long-Term Shoreline Changes near Indian River Inlet on the Delaware coast
Yan Ding, U.S. Army Corps of Engineer Engineer Research & Development Center
Along a relatively short and straight Delaware’s Atlantic Coast, shoreline configurations are largely determined by antecedent geology and inlet morphology, and variations of shoreline are influenced by offshore waves and anthropogenic factors (e.g. beach nourishment). These conditions play an important role in shoreline stability as well as evolution of shoreline positions and beach shapes. This research includes analysis of observed shoreline survey data and simulation of long-term shoreline evolution on the Delaware coast near the Indian River inlet. Major purpose of modeling shoreline changes is to reproduce historical shoreline evolutions driven by these environmental factors such as inlet sediment transport, offshore waves, longshore and cross-shore sediment transport, as well as shoreline protection practices such as beach nourishment and sand bypassing operation. The USACE shoreline evolution model, GenCade, is used for simulations of shoreline changes driven by both natural and engineering practice conditions, as it enables to simulate long-term shoreline variation by taking into account coastal structures, beach fills, inlets, and various boundary conditions. It has been widely used in coastal engineering projects for shoreline erosion protection, coastal sediment management, and coastal hazard management. Recent development of the model has enhanced the model’s capabilities to predict shoreline changes in response to cross-shore sediment transport processes, sea level rise, and subsidence. This presentation is to report preliminary validation results of GenCade by simulating twelve-year-long shoreline changes along the coastlines near the Indian River Inlet. The inlet reservoir model of GenCade is examined for simulation of sediment transport processes through the inlet. Model simulation skill is assessed by comparing simulated shoreline changes with observation data. Simulation results of shoreline evolution indicate that the model is capable of reproducing the shoreline response to natural conditions of waves and inlet sediment transport, beach nourishment, and sand bypassing process
Presenter Bio: Yan Ding is Research Civil Engineer in the Coastal and Hydraulics Laboratory, U.S. Army Engineer Research & Development Center, Vicksburg, MS. His expertise lies on hydraulics and river dynamics, wave dynamics, sediment transport, integrated coastal process modeling, dam-break flow modeling, and storm-surge modeling.
USACE Navigation Sediment Placement: An RSM Program Database (1998 – present)
Nicole Elko, Elko Coastal Consulting, Inc.
Co Authors: Nicole Elko, Katherine Brutsche, Quin Robertson
The USACE RSM Program funded APTIM and Elko Coastal Consulting to inventory Federal navigation projects Nationwide to determine the extent to which Regional Sediment Management (RSM) goals and beneficial use of dredged material have been implemented across the U.S. Army Corps of Engineers (USACE) Districts at the project and District levels. Data from the USACE Institute for Water Resources (IWR) Navigation Data Center’s Dredging Information System (DIS)
(https://www.iwr.usace.army.mil/About/Technical-Centers/NDC-Navigation-and-Civil-Works-Decision-Support/) were utilized and considerably refined using District managed information and data. A web-application, a District Specific/Quality Checked (QC) database, and a database of USACE DIS data specific to this project were produced. Also now visible is a separate online geodatabase called the ASBPA National Beach Nourishment Database which inventories U.S. nourishment projects (volume, length, cost) since the 1920’s.
In this study, the USACE DIS database is a largely unedited database extracted from the DIS. Due to varying degrees of data completeness, this study undertook a data refinement process to improve the information in the USACE DIS. The data refinement process described here transformed the USACE DIS into the District Specific/QC database.
This was done through interviews, literature search, and the inclusion of additional District-specific data provided by individual Districts that often represent more detailed information on dredging activities than available in the DIS. Several Districts provided an internally-maintained database for dredging projects. For the other Districts, the DIS data were manually edited to reflect the District specific information provided by the District during the interview and review process. The District Specific/QC database represents a customized, quality-checked database generated by this study.
In this presentation, the term “placement” generally refers to the beneficial use of dredged material and the term “disposal” refers to taking sediment out of the littoral system in a non-beneficial manner.
RESULTS: Of the approximately 200 to 300 Mcy of sediment dredged annually by USACE (EPA and USACE, 2007), this study analyzed an average of 214 Mcy removed annually from navigation projects from 1998 to 2018. USACE had previously estimated that 20 to 30 percent of the total volume dredged is placed beneficially (EPA and USACE, 2007). The USACE DIS confirms this statistic with an estimate of beneficial placement at 25% of the total volume dredged. However, the refined District Specific/QC database indicates that, in fact, 38% or 82 Mcy/yr of navigation sediment is placed beneficially.
This study also resulted in a substantial reduction in the volume of unknown disposal type. According to the USACE DIS, 43.1 Mcy/yr of navigation sediment was characterized as having an unknown disposal type. The refined District Specific/QC database identifies 2.9 Mcy/yr with an unknown disposal type. Additional interviews and refinement of this database may result in further reduction of the unknown volume.
Presenter Bio: Dr. Nicole Elko is the Executive Director of the South Carolina Beach Advocates, Science Director for the American Shore and Beach Preservation Association (ASBPA), and President of Elko Coastal Consulting, based in Folly Beach, SC. She is presently serving as one of the three civilian members of the U.S. Army Corps of Engineers’ Coastal Engineering Research Board (CERB). She serves a co-lead for the U.S. Coastal Research Program, a collaboration of federal agencies, academia, and NGOs. Dr. Elko received her Ph.D. (Geology) from the University of South Florida after working with the USGS Coastal Marine Geology Program, St. Petersburg, and while serving as the coastal coordinator for Pinellas County, FL.
RSM Regional Center of Expertise: Coastal Resiliency Initiatives in the South Atlantic
Clay McCoy, US Army Corps of Engineers
Regional Sediment Management (RSM) is a focus of the South Atlantic Coastal Study (SACS) and the Coastal Navigation and Flood Risk Management Program in the South Atlantic Division of the U.S. Army Corps of Engineers (USACE). In support of SACS, the RSM Center is managing a division-wide one-year Sand Availability and Needs Determination study that will define sand availability and needs for federal and non-federal beach projects throughout the South Atlantic for the next 50 years. The study is a collaborative effort between USACE, state and federal partners, and stakeholder throughout the study area.
Additional efforts to support coastal resiliency include Thin Layer Placement (TLP) and open water dispersal pilot projects in Georgia led by the Savannah District and supported by Georgia Department of Natural Resources, Jekyll Island Authority, The Nature Conservancy, and Atlantic Intracoastal Waterway Association. TLP is an emerging technique designed to support resiliency by increasing coastal marsh elevations in small lifts (<1 ft) to help combat the impacts of sea level rise on coastal marsh systems. The proactive pilot project was completed in May 2019 and includes two years of monitoring to determine the effectiveness of the technique in coastal Georgia which experiences the greatest tidal ranges in the south Atlantic. The open water dispersal project was designed to determine the effectiveness of open water dispersal as an economical and environmentally acceptable technique to keep dredged sediments in the coastal system. The presentation will highlight construction, monitoring results, and lessons learned to-date.
Presenter Bio: Dr. Clay McCoy is the Deputy Director of the USACE RSM Regional Center of Expertise in Jacksonville, Florida. Dr. McCoy has worked with at the Jacksonville District for eight years in the coastal navigation and flood risk management programs and focuses on implementing RSM projects throughout the South Atlantic Division. Prior to working at the Jacksonville District, he worked as a Coastal Process Extension Specialist for South Carolina Sea Grant and a Senior Research Scientist for Coastal Carolina University. He received his undergraduate degree from Clemson University in 1999 and PhD from East Carolina University in Coastal Resources Management in 2006.
Beach Nourishment Magnitudes and Trends in the U.S.: An Update
Lindino Benedet, Coastal Protection Engineering
Co Authors: Nicole Elko
Beach nourishment is the preferred method of coastal protection in the U.S. mainly because it preserves the aesthetic and recreational values of beaches while providing valuable storm protection for coastal communities. The U.S. has been nourishing its beaches since the 1920s, but up until recently, little was known about the magnitudes of the U.S. beach nourishment program and how it evolved over the years. About 12 years ago, Benedet and Campbell (2006) published an initial assessment of the U.S. beach nourishment program. The database developed by these authors evolved over the years in an effort led by the America Shore & Beach Preservation Association (ASBPA) and it morphed into what is now the ASBPA Nationwide Beach Nourishment Database, available online at www.asbpa.com. Benedet and Campbell (2006), using data prior to the year of 2004, reported a total volume placed on America’s beaches of 685M cy of sediments. Since then, an additional 500M cy of fill was placed on America’s beaches, and the nationwide effort coordinate by ASBPA was also able to reveal an additional 329M cy of fill that was placed in America’s beaches before the year of 2004 but not captured by Benedet and Campbell (2006).
The current ASBPA nationwide beach nourishment database demonstrates that, since the early 20s, 1.55B cy of sediments were placed on America’s beaches through about 3,000 nourishment events at an average fill density of 58 cy/ft. The volume placed on America’s beaches per year has steadily increased over the last ten decades, from a 5M cy/year in the 1920s and 1930s, to the 30M cy per year range over the last two decades, with an average for the entire period of 15M cy/yr. In the 1920s and 1930s, however, the volume originated from very few mega nourishments (>20M cy projects) as a result of major Federal civil works projects (Port Hueneme, San Diego Bay Deepening, Jones Beach and Rockaway Beach in NY). In the 1920s, for example there were only 20 projects placing 44M cy on America’s beaches. That is a huge contrast that with the 2000-2009 period, where 323M cy of sediments were placed on America’s beaches through a whopping 793 projects. The 2000s was marked by intensive Hurricane activity, in 2006, following the most active hurricane season in recorded history, 42M cy of sediments were placed mostly on beaches impacted by Hurricanes.
In this presentation the authors will graphically highlight interesting and curious facts about the nationwide nourishment program with focus on temporal and spatial trends in fill volumes and fill densities, types of projects, sources of funding (federal vs state & local), significance of the RSM component, effects of storms and SLR on nourishment activity and expected future trends. An in-depth analysis of selected state programs will also be conducted to compare and contrast practices in different states and highlight lessons learned.
Presenter Bio: Lindino Benedet has over 18 years professional experience dedicated to the coastal engineering. Lindino obtained his undergraduate degree at UNIVALI in Brazil, where he majored in Oceanography, received his master’s degree at Florida Atlantic University in Marine Geology under Dr. Charles Finkl and obtained his Ph.D. at Delft Institute of Technology in Delft, Holland, with focus on Hydraulic Engineering under the supervision of Prof. Dr. Marcel Stive. He is an Associate Editor Shore & Beach and of the Journal of Coastal Research. Lindino has worked on hundreds of consulting projects and published dozens of scientific papers in international journals and conferences. His expertise includes project and business management, process-based numerical modeling of coastal processes, marine geology and marine met-ocean studies & measurements, feasibility studies, dredging, beach nourishment, barrier island restoration, coastal structures, marine sand searches etc. Over the last couple years Lindino has worked with many state and local governmental agencies in the states of Florida, Louisiana, Texas and North Carolina as well as private clients in the O&G industry and ports in the USA and internationally.
Upham Beach T-Groins 6 Months Post Construction
John Bishop, Pinellas County
Co Authors: Andrew Squires, Thomas Pierro
This presentation will briefly discuss the history of the Upham Stabilization Project including the performance of 5 temporary geotextile groins and the initial 6 month performance of the 4 rock groins that have replaced them.
Upham Beach is located just south of Blind Pass at the south end of Pinellas County which is located on the south-central gulf coast of Florida. Upham Beach is a hot spot for erosion. During the 1997-1998 El Nino Upham Beach eroded at a rate of 1.4 ft/day. In 1992 the Blind Pass Inlet Management Study proposed stabilizing the beach with groins. By 1999 the final permit application to build 5 temporary geotextile T-groins was submitted to the state of Florida and the permit to construct the groins was approved in 2003. This first attempt to stabilize Upham Beach completed construction in 2006. These groins greatly improved sand retention on the beach which retained 40% more sand post construction than prior to construction. In 2017 construction began to remove the geotextile groins and replace them with 4 rock T-groins which reached final completion October 2018. The 6 month post construction physical monitoring survey was completed in April 2019 and the physical monitoring report will be submitted to the Florida Department of Environmental Protection early summer 2019.
The addition of 5 geotextile groins to Upham Beach have reduced the volume of sand needed for nourishment by about 100,000 cubic yards. This volume represents a cost savings on the order of $1 million dollars per project. Pinellas County anticipates that the permanent rock groins will add further cost savings by increasing the time between nourishment.
Presenter Bio: John Bishop completed his Bachelor’s degree in geological sciences at the State University of New York at Buffalo. After moving to Florida, he received his Master’s in Geological Oceanography and Doctorate in Oceanography from Florida Institute of Technology in December 2013. Soon after graduation John was hired by Pinellas County and assumed the position of Coastal Management Coordinator where he has worked for 6 years.
Plant Materials and Fencing for Coastal Dune Stabilization
Tommy Socha, USACE Charleston District
The U.S. Army Corps of Engineers, Charleston District (Corps) has been constructing storm damage reduction projects on South Carolina beaches since 1993. The last phase of these projects is the grassing and fencing phase which helps with stabilization of the dunes and to build up the sand dunes on the re-nourished beaches.
Over the years, the Corps has constructed 11 grassing and fencing projects from Folly Beach, just south of Charleston, to North Myrtle Beach, just south of the North Carolina border. These projects involved installation of V-shaped fence panels, plants and signage covering approximately 60 miles of beach. The grass and fencing traps wind-blown sand and has been very successful in building large dunes along the SC coastline. Dunes have reached heights of 8 ft. and widths of 40 to 50 ft. at the base. The dunes help reduce the damage to the infrastructure, provide excellent protection for human safety and personal property for towns and cities along the S.C. coastline from high tides caused by storm events.
Due to the recent increase in storm events and increased public use of our beaches, the Corps is working with local sponsors to revise the original fencing and grassing designs and installation locations on these beaches. These revisions have been successful in providing additional protection to dunes constructed by the local sponsors and has helped maximize the beach at high tide for public use.
Presenter Bio: Tommy Socha has spent 40 years working with plant material to build sand dunes along the South Carolina coastline. In 1985, he transferred to the US Army Corps of Engineers, Charleston District where he has worked for the last 34 years. His work has included- writing plans and specifications for grassing and sand fencing projects and supervising the planting of over 3.5 million beach plants and installation of approximately 60 miles of sand fencing to provided protection for South Carolina beaches. He was employed with the Charleston Soil and Water Conservation District and Soil Conservation Service for 6 years. Tommy attended Brevard College and earned an Associate’s Degree in Agriculture Science from Trident Technical College.
Updates to USACE’s automated feature detection of dunes and bluffs and ground-truth opportunities with the DUNEX project
Eve Eisemann, USACE ERDC
Co Authors: Hartman Michael, Dunkin Lauren, Wozencraft Jennifer
An algorithm was designed to automatically locate the foredune crest, foredune toe and highest dune ridge along the entire coastline of Texas using 2012 and 2016 JALBTCX lidar datasets. This work was completed to assist Galveston District. The USACE great lakes districts then requested that bluff edges and toes be extracted from the 2012 JALBTCX lidar collection in that region. In response to this request, an algorithm was built on the same foundation as the dune-detection algorithm to locate the edge and toe of bluff features. Current work focuses on improving the effectiveness of these codes across various coastal systems by adjusting user-input thresholds and migrating to an Arc Python environment from the original Matlab scripts.
The During Event Nearshore Experiment (DUNEX), conducted by the U.S. Coastal Research Program, provides an opportunity to collaborate with a variety of agencies, academic institutions to study the effects of storms on the coast. This provides an opportunity to ground-truth automatically detected dune features using field surveys and quantify relationships between storm response metrics (dune erosion, breaching locations, etc.) and these auto-detected coastal parameters (dune height, dune volume, beach width). This provides an invaluable opportunity to establish relationships that can then be applied nation-wide.
Presenter Bio: Ms. Eve Eisemann is a Research Physical Scientist in the Coastal and Hydraulics Laboratory (CHL) with the U.S. Army Engineer Research and Development Center (ERDC). She works from the Joint Airborne LiDAR Bathymetry Technical Center of Expertise (JALBTCX) in Kiln, Mississippi. Ms. Eisemann has contributed to research addressing barrier island systems and their geomorphology, coastal storm impacts, submerged aquatic vegetation habitats, Holocene sea-level rise and paleo-environmental indicators. She is currently working on projects employing Light Detection and Ranging (LiDAR) data to calculate beach volumes, shoreline changes, and coastal resilience.
Mapping Inlet Hazard Areas
Spencer Rogers, NC Sea Grant
Co Authors: Ken Richardson, William Birkemeier, Elizabeth Sciaudone
The presentation will describe a project to map inlet hazards in North Carolina. Unstabilized inlets offer substantial challenges for coastal management. Some inlets migrate relatively persistently at sometimes spectacular erosion rates. Some inlets are fixed in location by underlying geology or hydraulic issues but the inlet shoreline wobbles around at much higher rates of change compared to ocean shorelines more distant from the inlets. The volatile hydraulics of tides and shoals affect not just the inlet shorelines but also the ocean shoreline at times distant from the inlet. The analysis used shoreline and vegetation lines from historical photography to map the higher variability in context with other coastal management regulations on the oceanfront.
NC Science Panel on Coastal Hazards, 2019, Inlet Hazard Area Boundary, 2019 Update, NC Division of Coastal Management, February, 119 pp.
Presenter Bio: Coastal engineer/geologist with North Carolina Sea Grant.
Using UAS photogrammetry and airborne lidar to evaluate surface change detection of an undeveloped beach following Hurricane Michael
Kelsi Schwind, Texas A&M University – Corpus Christi
Co Authors: Michael Starek, Jake Berryhill, Alistair Lord
Remote sensing techniques have been widely adopted to evaluate highly dynamic coastal environments and monitor beach evolution over time. There is a great need to continue surveying these environments to predict their vulnerability to future events, such as sea level rise and episodic storms. Unmanned aircraft systems (UAS) have demonstrated their capability to generate high resolution 3D point clouds and bare earth digital elevation models (DEMs) that can be utilized to evaluate coastal evolution in a cost and time – effective manner.
We assessed the volumetric changes of a beach and its changes in dune height for Little St. George barrier island located near Apalachicola, Florida to evaluate the impacts of Hurricane Michael after it made landfall. High-resolution UAS imagery were obtained in July, 2018 prior to the landfall of Hurricane Michael using a SenseFly eBee Plus equipped with an eBee S.O.D.A RGB camera. Structure-from-motion techniques were applied to generate a 3D point cloud and a bare earth DEM from the UAS imagery. A DEM was obtained from NOAA Digital Coast and derived from airborne lidar collected after Hurricane Michael by the U.S Army Corps of Engineers following the storm’s landfall in October, 2018. The resulting DEMs were compared to quantify volumetric changes of the beach and dune height for Little St. George Island after the landfall of Hurricane Michael, and the reliability of the UAS data was determined by assessing its horizontal and vertical accuracy. Future work will continue to utilize these datasets to measure various indices to determine the island’s vulnerability to future episodic storms.
Presenter Bio: Kelsi Schwind is a Coastal and Marine System Science doctoral student at Texas A&M University – Corpus Christi. Her research includes utilizing various remote sensing techniques to evaluate coastal change and to determine how surveying techniques can be adopted for future conservation efforts.
“Evaluating UAS Surveying for Monitoring of Oiling Events on Sandy Beaches”
Michael Starek, Texas A&M University-Corpus Christi
Co Authors: Jake Berryhill
When a pollutant such as oil washes upon a beach, it is important to monitor its position as cleanup operations are performed. Historically, beach oiling events have been monitored using the Shoreline Cleanup and Assessment Technique (SCAT). While these practices can monitor whether or not oiled beach is present, they are ineffective at precisely and accurately determining the amount of sediment accretion or erosion that may have occurred thereby burying or removing oiled sediment, respectively. Such traditional “field surveying” methods are also labor intensive and costly. These facts encouraged an interest in examining structure-from-motion (SfM) photogrammetry using a small unmanned aircraft system (UAS) as an alternative approach for monitoring beach oiling.
The main goal of this analysis is to quantify the level of beach elevation change detectable with UAS-SfM photogrammetry based on various georeferencing and control methods. A sandy beach study site on Mustang Island located along the Texas Gulf coast was used as a test bed for this experiment. Four georeferencing schemes for the UAS data are evaluated for their ability to resolve surface elevation change: (1) traditional ground control target network; (2) RTK GNSS geotagging of acquired imagery using real-time broadcast solutions from a virtual reference station (VRS) network; (3) RTK and PPK GNSS geotagging of acquired imagery using a local base station; (4) on-board geotagging using a single-channel, non-differential GNSS. Surveys were performed daily for three consecutive days at low tide using both UAS and terrestrial lidar that serves as a “ground truth” measurement source. Single flight and temporal changes in elevation computed from the UAS surveys were compared and RMSE values computed to quantify vertical accuracy of each UAS survey method. In this presentation, examples of UAS videography and rapid processing for scouting of oiling events will be shown along with results from the UAS-SfM field experiment. For the latter, emphasis will be on the accuracies of the different survey methods employed to map beach elevation for buried oil change detection.
Presenter Bio: Dr. Michael “Mike” J. Starek is an Associate Professor in Geospatial Systems Engineering at Texas A&M UniversityCorpus Christi (TAMU-CC) and Director of the Measurement Analytics (MANTIS) Lab with the Conrad Blucher Institute for Surveying and Science. Starek holds a Ph.D. in Civil Engineering from the University of Florida and was formerly a National Research Council Postdoctoral Fellow of the U.S. Army Research Office in affiliation with North Carolina State University. His research focuses on the merging of geomatics, remote sensing, and geospatial computing for precise measurement and analysis of natural and built environments.
Coastal River Flooding Caused by Extreme Rainfalls in South Carolina
Hongyuan Zhang, Coastal Carolina University
Co Authors: Shaowu Bao, Paul Gayes, Leonard Pietrafesa
Hurricanes Joaquin (2015), Matthew (2016), Irma (2017), Florence (2018) and Michael (2018), and their associated heavy rainfalls struck the US East Coast and caused extensive flooding in four consecutive years. These flooding hazards are receiving increasing attention because over 39% of the U. S. population is living in coastal regions and the Intergovernmental Panel on Climate Change (IPCC) Report projects sea level rise and more frequent heavy rainfalls associated with climate changes and global warming. During a hurricane landfall, its’ wind pushes water onshore to drive storm surge and ocean water inundation, and its rainfall causes inland fresh water flooding. How these two processes affect each other has not been extensively studied, with the former mainly being forecast by oceanographers and the latter by hydrologists. In this study, a physics-based hydrological-oceanic coupled model is employed to investigate the river-ocean interaction during hurricanes at several coastal river basins in South Carolina, and the findings from these numerical studies will be presented.
Presenter Bio: Hongyuan Zhang is PhD student of marine science at Coastal Carolina University. Hongyuan’s research is about the interactions between river system and ocean at coastal region.
Creating Urban Flood Resilience in Norfolk’s Ohio Creek Watershed
Brian Joyner, Moffatt & Nichol
The City of Norfolk’s Ohio Creek Watershed Transformation project, funded by a National Disaster Resilience Competition (NDRC), will increase resilience of the Chesterfield Heights and Grandy Village neighborhoods to tidal, storm surge and precipitation flooding by: constructing a berm and floodwall system along the shoreline; constructing living shorelines and wetlands; constructing two high-capacity pumping stations; and replacing / upgrading all of the existing storm drainage infrastructure and installing Green Infrastructure as bioretention cells at most of the neighborhood’s intersections. Design of the storm drainage conveyance infrastructure and Green Infrastructure required a high level of coordination with the coastal flood protection design, landscape architecture of community park amenities, and existing public and private subsurface utilities (primarily water, sanitary sewer and natural gas). In addition to the basic challenge of ensuring sufficient drainage for peak runoff rates to avoid surface flooding, the stormwater design faced challenges of avoiding or resolving subsurface conflicts with constrained vertical room to work, and supporting the creation of a compelling urban landscape architecture and park design – such as avoiding conflicts with existing and planned trees, adapting to frequently-changing park features and wetland designs, and conveying stormwater in narrow passages between coastal protection and existing homes. The presentation will give examples of each of these challenges, will describe the various ways that the design team resolved them, and will conclude with lessons learned that can be applied to future similar projects.
Presenter Bio: Brian Joyner is a coastal engineer at Moffatt & Nichol who focuses on the planning and design of coastal resilience infrastructure projects. A graduate of NC State University, he specializes in detailed modeling and analysis, and incorporating data and modeling results into both high-level resilience planning and detailed design of infrastructure projects. He is currently leading Moffatt & Nichol’s involvement in several shoreline protection, dune management, coastal flooding/sea level rise, and stormwater projects for Hampton Roads communities.
Where Rivers Meet the Coast: A Story About Accelerating Headwater Land Protection in the Mobile Bay Watershed
Kari Servold, Moffatt & Nichol
Co Authors: Dan Dumont, Roberta Swann, Eldon Blancher
The Mobile Bay National Estuary Program (MBNEP) was awarded an EPA Healthy Watershed Grant in 2018 to advance the strategic protection of healthy headwater habitats located within the Mobile Bay watershed. The Mobile Bay watershed contains 75% of the first and second order stream catchments that eventually drain into Mobile Bay, which are important headwater habitats that have large effects on the water quality and ecological health of the entire bay, estuary, and coastal Alabama waters. This presentation will provide an overview of the Accelerating Headwater Land Protection in the Mobile Bay Basin project and its achievements to date. Specifically, this presentation will describe the processes behind the project’s GIS and data analysis and its development of a Mobile Basin Habitat Atlas, which identifies healthy, priority headwater habitat parcels for land acquisition or conservation easement that are important to protecting the health of the Mobile Bay estuary. This Atlas will be utilized by the Alabama Forest Resources Center (AFRC), a local land trust, to identify landowners amenable to selling or putting their land under conservation easement with a goal protecting 10,000 acres of priority headwater habitats over the two-year period of the grant. Long-term, this program will seek to place 100,000 acres of identified priority headwater habitats in protection via acquisition or conservation easement over a period of five to 10 years. In summary, this grant is providing an opportunity to be strategic in land conservation to meet environmental goals in support of a healthy Mobile Bay estuary and will accelerate the protection of important headwater habitats of the Mobile Bay watershed. As such, this project is truly about supporting areas where rivers meet the coast.
Presenter Bio: Ms. Servold has five years of experience providing watershed management planning (WMP) and engineering consultation services in coastal Alabama. Ms. Servold is passionate about watershed management and is working towards becoming a professional coastal engineer.
An Analysis of Vessel Generated Wakes in the Hudson River
Taylor Zimmerman, Stevens Institute of Technology
Co Authors: Hoda El Safty, Jon Miller
The objective of this analysis was to analyze vessel generated wakes in the Hudson River. Lincoln Harbor Yacht Club in Weehawken, New Jersey was the site location of this study. The problem investigated was to determine if vessels were responsible for the wakes that induced negative impacts on the Lincoln Harbor Yacht Club. For the past twenty years, large wakes have disrupted the marina by inflicting damage on its docks, pilings, and boats, which swing and sway in the wakes thus put strain on the ropes and docks structural integrity.
The study was set up by installing two wave gauges, each programmed to record water level data at 30 Hz (which was subsampled to 10 Hz) for one week to provide a time history of wave heights and tidal elevations. One gauge was placed outside of the marina and the other inside of the marina, which is separated by a barge and wave screen. The wave screen was installed around 2000 in effort to attenuate vessel generated wakes, and the barge was introduced in (YEAR) for the same purpose. The analysis was performed by identifying the individual waves recorded at each gauge and comparing the wave heights at the outside gauge and inside gauge. This analysis produced an understanding of how efficiently the barge and wave screen attenuated waves through a time series of wave heights for both gauges.
The major patterns in the data suggest that the majority of energy at this site was associated with vessel generated wakes in the Hudson River outside of the marina. Peaks in energy were during morning and evening rush hours, which is likely a result of ferry activity. The ability of the barge and wave screen to attenuate waves was calculated using a percent reduction over the average wave height for 15-minute intervals. Over one continuous week of data collection, the average percent reduction was found to be 61%. The effectiveness of the barge and wave screen varied with wave steepness, as they were more effective in reducing wave energy with a wave steepness of 0.01 or greater. Overall, the wakes that are yielding negative effects on the Lincoln Harbor Yacht Club are likely due to the ferries, and the barge and wave screen are effective under certain wave conditions.
Presenter Bio: Taylor Zimmerman graduated from Rowan University with a B.S. in Civil & Environmental Engineering. She worked as a coastal engineering intern for Mott MacDonald and spent two summers as a coastal engineering research assistant at Stevens Institute of Technology. She began her masters in the fall of 2018 at Stevens under the advisement of Dr. Jon Miller. Taylor is currently serving as President for the Student Chapter of ASBPA at Stevens Institute of Technology.
Can the Trash! Clean Beach Poster Contest
Susana Espinosa, County of Los Angeles Department of Beaches & Harbors
Can the Trash! Clean Beach Poster Contest is a creative educational and environmental messaging campaign from the County of Los Angeles Department of Beaches and Harbors. The campaign is an effort to combat the significant problem of run-off pollution affecting our beaches, local marinas, and ocean bays. It uses the tagline “Because ocean pollution begins at home” to bring awareness to the main sources of pollution affecting the health of our local beaches and ocean waters. Through youth education, the campaign also seeks to encourage a life-long interest in our coasts.
Aimed at elementary school children, Can the Trash! teaches young students that trash and pollutants from across the County can make their way into the storm drains and natural watersheds to eventually wash out on our local beaches, becoming a major cause of ocean pollution. The lessons reinforce that environmentally-conscious habits at home and in their local neighborhoods can make a positive impact on both the cleanliness of our beaches and the water quality of the ocean.
Two key educational pieces were created as the framework to support the contest and overall messaging. They are the Ocean Heroes Activity Guide, a colorful book with activities and games covering the various causes and consequences of pollution, and the animated song video “Clean and Blue” featuring a catchy pop tune that voices the ocean’s plea for our help to stay healthy. A dedicated website makes the educational materials easily accessible and artwork submissions can be uploaded directly to the site. Featuring multi-media elements aimed to deliver the educational material from various formats, including video, music, and print, the campaign thereby casts a wide net of appeal for various kinds of learners.
After working on the activity guide and watching the video, 3rd – 5th-grade students are asked to create artwork with a message about protecting our beaches and ocean, and/or why it is important to be good environmental stewards of our coast. The Clean Beach Poster Contest is the tool the campaign employs to engage students and foster the environmental stewardship needed from our youth to preserve and enhance our beaches and ocean life for future generations. The winning artworks are wrapped and featured on 1,200 trash barrels across County-operated beaches. In doing so, an unlikely resource, the beach trash barrel, is used as a vehicle delivering powerful messages boosting environmental awareness in the beach-going public. By displaying the winners’ artwork on trash barrels seen by an estimated 70 million of visitors yearly, the broad message about the environmental responsibility we all bear to stop pollution before it reaches the ocean is amplified.
In its inaugural year, enough quality entries were received to select one winner from each grade level in each of the County’s five supervisorial districts for a total of 15 winners. The messages and ideas expressed in the drawings showed an understanding of the sources of pollution and the role we play through our daily actions, further demonstrating that youth care about their environment and want to protect it.
Presenter Bio: Susana Espinosa serves as program manager within the Community and Marketing Services Division of the Department of Beaches and Harbors. Susana holds a degree in Recreation from UNLV. She joined the County of Los Angeles in 2009 with the Department of Parks and Recreation. Later, Susana transferred to Beaches and Harbors where she managed the Recreation Section. Susana briefly served as Section Head of Beach Permits before becoming the Division’s program manager. Current projects/programs include an environmental messaging campaign, a pop-up arts festival in Marina del Rey, and a youth water safety and recreation program led by LA County Lifeguards.
Certified Coastal Practitioner (CCP) Program
Gordon Thomson, Coastal Zone Foundation
Co Authors: Lee Weishar, Kate Gooderham, Tom Richardson
In the 21st century, there is a growing need to have a diversified knowledge base that spans many fields for a practitioner working in the coastal zone. There is also a need to define the body of knowledge that reflects best practices for coastal professionals and will address and advance a profession that has come into its own. The Coastal Zone Foundation has taken on a new mission to develop and implement a Certified Coastal Practitioner (CCP) program to recognize coastal practitioners who have this broad range of knowledge and dedication to continue to expand their coastal experience.
The program consists of a series of short courses including:
These courses will provide coastal professionals from government, consulting and academia a series of short courses structured to expand and grow their understanding of the multidisciplinary aspects of the coastal zone. This will increase their proficiency and competitive advantage.
In addition, these courses will: 1) define what the coastal industry (science, government and nongovernment organizations) expects, 2) identify qualified individuals, 3) set a standard and require concurrence to a code of ethics, 4) require and encourage ongoing education, and 5) enhance Coastal Zone Foundation’s reputation as a coastal zone leader.
Following initial certification, Certified Coastal Practitioners are required to renew their certification every 5 years for it to remain valid. The objective of renewal is to encourage certificate holders to remain active in and contribute to the coastal field, thereby ensuring that the certificate itself retains meaning and purpose.
The presentation will highlight the benefits of the CCP program, provide a summary of the various short courses, the base requirements for initial certification and process for recertification.
Presenter Bio: The Coastal Zone Foundation is continuing a tradition of encouraging rigorous research and continued collaboration to nurture, protect and manage the coastal zone through sound science, engineering and planning.
Deaggregation of multi-hazard damages, losses, risks, and connectivity: An application to the joint seismic-tsunami hazard at Seaside, OR
Dylan Sanderson, Oregon State University
Co Authors: Sabarethinam Kameshwar, Hyoungsu Park, Mohammad Alam
Multi-hazard damage analyses can prove useful for quantifying the overall impact to communities resulting from natural hazards. However, understanding the relative contribution of single-hazards within a multi-hazard framework is imperative for effective mitigation planning and efficient resource allocation. In this work, a methodology for deaggregating a multi-hazard damage analysis is presented. The methods are applied to the joint seismic-tsunami hazard at Seaside, Oregon resulting from a rupture of the Cascadia Subduction Zone. Four infrastructure components are considered: (1) buildings, (2) electric power network, (3) transportation network, and (4) water supply network. Damages to all infrastructure components are evaluated, and the networked infrastructures are used to inform tax-lot connectivity to critical facilities. US Census Block data and a probabilistic housing unit allocation method are implemented to assign detailed housing unit demographic characteristics at the tax-lot level. The damages, economic losses, economic risks, and connectivity to critical facilities are deaggregated by infrastructure, hazard, and population characteristics. Considering economic risks as opposed to economic losses highlight the importance of planning for the 250- to 1,000-year event rather than the “worst-case” scenario. Geospatial representation of the results allow for the identification of vulnerable areas within a community, and is highlighted by the spatial pattern of tax-lot disconnection from critical facilities. To make these findings accessible for other researchers and facilitate communication with stakeholders, cloud-based interactive Jupyter Notebooks have been developed that allow for geospatial visualization of the deaggregated results.
Presenter Bio: Dylan Sanderson is a PhD student in the School of Civil and Construction Engineering at Oregon State University. His current research focuses on probabilistic multi-hazard damage analyses and is using the joint seismic-tsunami hazard at Seaside, OR as a testbed. Prior to attending OSU, Dylan worked at the U.S. Army Corps of Engineers’ Research and Development Center on the development of probabilistic lifecycle analysis models for coastal storm risk management. Dylan received his Bachelors of Science from Texas A&M University in 2016.
Southern Currents: Equity & Inclusion in Water Management Projects
Jessica Hardesty Norris, Biohabitats
Co Authors: Marilyn Hemingway, Gullah Geechee Chamber of Commerce
Our experience supports environmental justice research showing that the distribution of living infrastructure and shoreline enhancements can disproportionately benefit white and affluent communities. Therefore, modern perspectives on planning must carefully note who pays for projects, who benefits, and who makes decisions up and down the watershed. As we intensify our resilience planning, practitioners share lessons from their work creating equitable and inclusive projects. Georgetown, SC, is the only SE coastal site for a UN Sustainable Development Program (Georgetown RISE). We will share lessons from workshops in an economically and racially stratified county as well as perspectives from a broader analysis of the points in decision making where authentic community engagement and equity considerations are most important, with a focus on how consultants can improve their reach. We plan to share challenges and successes in advocating for inclusive practices with clients and design teams. What can consultants do better?
Presenter Bio: Dr. Jessica Hardesty Norris is a Conservation Ecologist with Biohabitats, Inc.
The Fight of Our Lives: Hazard Mitigation Strategies for Rising Seas
Doug Bellomo, AECOM Water
Co Authors: Darryl Hatheway
Read the headlines:
This presentation will look at flood risk management strategies to mitigate the impact of rising seas on economic, social, and environmental systems in the US. This presentation will examine the effectiveness of current strategies at managing risks to those systems posed by rising seas – both along the open coast and within bays and estuaries. It will look at the advantages and disadvantages of structural, non-structural, and hybrid approaches such as long-term coastal protection using gray infrastructure (sea walls, revetments, and beach nourishment), approaches such as zoning, land use planning and building codes, and green-gray approaches where natural features are combined with hard scaping to achieve multiple objectives. This presentation will also look at the examples and successes of mitigation strategies for rising seas using hard defenses, soft defenses, foundation elevation, floatable foundations, and managed retreat. Questions to be discussed include:
Presenter Bio: Doug Bellomo is with AECOM leading their flood risk management and resilience practice. Previously Doug served as a senior flood risk management technical advisor at the USACE Institute for Water Resources working in Dam and Levee Safety, the National Flood Risk Management Program, as well as coastal and floodplain management services. Doug also served as Director of the Risk Analysis Division at FEMA where he oversaw implementation of the Risk Mapping, Assessment, and Planning (Risk MAP) program, the National Dam Safety Program, HAZUS, and Mitigation Planning. Doug is a professional engineer with an MS and BS in Civil Engineering.
Adaptive Planning for Sea Level Rise and Recurring Storm Effects Specifically for Local Governments
Douglas Mann, Aptim Environmental & Infrastructure, Inc.
Co Authors: Ken Willson
While many sea level rise adaptation guidelines provide a general framework for the qualitative and quantitative assessment of the vulnerability of future changes on public and private infrastructure (for example FDEP (2018), NOAA (2010)), experience in undertaking these planning and engineering efforts suggests that an incremental planning and implementation effort may better serve many coastal communities. With the relative sea level rise affecting large portions of the US coast at manageable rates, the use of adaptive management planning and implementation is advantageous to local governments for a variety of reasons:
With these advantages explained, a strategy for local governments to undertake location specific vulnerability assessments and adaptation planning will be presented. While there is no one size fits all strategy, the use of adaptive management will give government the time and flexibility to appropriately responds to sea level rise and coastal storm effects.
FDEP, “Florida Adaptation Planning Guidebook,” June 2018
Haasnoot, M. Kwakkel, J., Walker, W., and Maat, J., “Dynamic Adaptive Policy Pathways: A Method for Crafting Robust Decisions for a Deeply Uncertain World., “, Global Environmental Change, Vol 23, pp.485-498, 2013.
NOAA, “Adapting to Climate change: Planning Guide for State Coastal Managers,” 2010.
Presenter Bio: Douglas W.Mann, P.E., D.CE. has provided coastal engineering services to governmental and private clients for over 32 years. His expertise includes beach nourishment, inlet studies, coastal structures and seal level rise resilience.
Coastal Resiliency Planning: Bridging the Gap between Natural and Human Environments
Taylor Nordstrom, AECOM
Co Authors: Chris Levitz, Joshua Oyer
The 2019 Texas Coastal Resiliency Master Plan (Resiliency Plan) opens a discussion on the interaction between growing human infrastructure in coastal environments and the natural ecosystems that have existed in the same narrow coastal zone throughout the historical development of Texas. This presentation will describe the steps that the Texas General Land Office is taking to integrate the concepts of ecological and infrastructure resiliency into its planning and priority project identification process. The many coastal towns and cities that are present today along the Texas coast reflect the dynamic interchange between humans and the environment. It often happens during planning processes that natural and man-made environments are separated into discrete plans for simplicity, rather than considered as one integrated system. However, these environments are susceptible to the same storms, droughts, floods, sediment restrictions, and other vulnerabilities that shape the life of the coast. Moreover, areas that do not have robust protections on both man-made and environmental fronts are generally more susceptible to risks imparted by coastal vulnerabilities. This discussion will delve into how the Resiliency Plan worked to bring diverse stakeholders together to collaborate for a more resilient coast to the benefit of both communities and the environment alike.
The role natural ecosystems play in protecting and enhancing human environments has continued to take a more prominent role in the larger picture of coastal resiliency, to the point where natural ecosystems can reasonably be recognized and considered as natural infrastructure. The Resiliency Plan explores the Texas-specific interplays between nature-based and human environments to better understand how these environments depend on one another for growth and productivity, as well as how man-made and natural environments can be improved to better support and mitigate risk. In addition, the Resiliency Plan looks at how to better integrate improvements in technology, science, and known conditions to improve the future development along the Texas coast in a way that promotes communities while recognizing the benefits of a healthy environment for current and future generations.
The presentation will detail some of the data-driven assessments of habitat and land cover change projected over the next 80 years due to just one major coastal vulnerability, relative sea level rise, using the Sea Level Affecting Marshes Model (SLAMM). It will also explain the basis of assessing value added by coastal environments through considering ecosystem services. Still ongoing is modeling work to describe the expected benefits (through reducing economic damages) of large-scale wetland restoration and beneficial use of dredged material by mitigating storm-induced flooding. This modeling work continues to be refined through ongoing efforts to better defend how environmental resilience bolsters community resilience.
For community infrastructure-based efforts, the presentation will describe some of the means used to defend the value added by infrastructure to the coastal economy, as well as how coastal resources benefit human enterprises. The 2019 Resiliency Plan, on a regional basis, expresses the socioeconomic value of Texas coastal cities and communities, and identifies priority projects needed to better protect coastal infrastructure and, above all, human life.
Presenter Bio: Ms. Nordstrom is a coastal engineer with AECOM based in Houston, Texas. Her engineering experience includes coastal design and restoration on the Gulf Coast, specializing in resiliency master planning and living shorelines. When she’s not at the beach, her hobbies include hiking, singing, and eating as much Indian food as Houston has to offer.
Fair Weather Flooding and Sea Level Rise in the Florida Keys: A Case Study at the Marathon OCB Radio Broadcasting Site
Patrick Snyder, AECOM
Co Authors: Elena Drei-Horgan, Laura Cherney, Rod Mercer
The Florida Keys are ground zero for sea level rise impacts in the United States. While catastrophic coastal flooding events, exacerbated by rising seas and strengthening storms, threaten the entire US coast, there is no region where chronic “blue sky” (fair weather) flooding is more pressing an issue than in the Keys. This chronic flooding is here explored through summary of an assessment of site flooding and shoreline erosion at the Office of Cuba Broadcasting (OCB) medium-wave radio transmission site in Marathon, Florida. It presents preliminary recommendations for management of the site relating to impacts from coastal hazards, namely flooding, erosion, and wave action as induced by tides and storm events, and exacerbated by sea level rise.
The transmission site is located in the Middle Florida Keys, within the limits of the City of Marathon, on an island of reclaimed land separated from Boot Key by Sister Creek and connected via a short causeway to the main island of Vaca Key. The island, which occupies approximately 40 acres, has an average elevation of about 1.8 feet NAVD88. Rising seas will only increase the threat to the island. Under all but the lowest current NOAA and USACE sea level rise projections, it is expected that flooding of a majority of the island will be a daily occurrence by 2100 and possibly as early as 2045. The entire island may indeed be under water by the end of the century. Various measures are proposed to mitigate for and adapt to the threats of rising seas and strengthening storms.
This presentation will focus on the assessment of the coastal hazards currently impacting the site and will highlight suggested mitigation alternatives. The coastal threats faced by this site are facing the Florida Keys in general. As such, the mitigation and adaptation measures proposed here may also be applicable on a larger scale. Average elevations throughout the Keys are only a few feet higher than the current sea level and elevated areas are scarce. Without intervention, rising seas will drastically alter the accessibility, safety, and livability of the Keys over the next century. The Florida Keys of the future may be markedly different than that of today. It is imperative that all involved stakeholders coordinate their efforts to assess the realistic prospects for the future of the Keys and begin implementing appropriate adaption measures.
Presenter Bio: Patrick J. Snyder, PE, is a coastal engineer with AECOM with ten years of experience in all aspects of coastal engineering project formulation and implementation from engineering feasibility studies and design through bidding and contract preparation, construction oversight, and project monitoring for beach restoration projects and coastal structures throughout the southeast. His work has focused mainly on the design and construction of large-scale beach nourishment projects and, more recently, the modeling and analysis of coastal flooding hazards in support of FEMA flood insurance studies. He is registered as a PE and CFM in the State of Florida.
Going Under: Severe Repetitive Loss Properties and Buyout Assistance in Coastal Areas
Anna Weber, Natural Resources Defense Council
Co Authors: Rob Moore
As of May 2018, the National Flood Insurance Program (NFIP) has paid $7.4 billion to repair and rebuild more than 36,000 “severe repetitive loss” properties (SRLPs). These homes and businesses have been rebuilt multiple times in the wake of hurricanes or other flood events and are the most flood-prone properties insured through the NFIP. And while FEMA has spent over $13 billion on hazard mitigation since 1989, less than one-third of SRLPs have received mitigation to reduce future flood risk.
Meanwhile, FEMA’s Hazard Mitigation Assistance grant programs have supported the purchase of over 43,000 properties via state and local buyout programs, but these projects take over five years, on average, to reach completion after a disaster. In the U.S., flood insurance is usually the only timely assistance accessible to owners of repeatedly flooded homes, and it generally pays only to rebuild in the same vulnerable location. For homeowners who want to move, assistance is hard to find. NRDC estimates that sea level rise may create millions more SRLPs by the century’s end, with the U.S. spending hundreds of billions of dollars to repeatedly rebuild flood-prone structures.
This presentation will summarize available information on SRLPs and FEMA-funded buyouts in coastal areas, as well as policy recommendations for streamlining the delivery of mitigation funding for voluntary buyouts. NRDC has developed a proposal to pre-approve interested low- and middle-income homeowners for future buyouts, breaking the cycle of “flood, rebuild, repeat” and eliminating the long waits and uncertainties common to current efforts.
Presenter Bio: Anna Weber’s work focuses on the intersection of water and climate change, including flood risk mitigation and coastal resilience. Prior to joining NRDC, she spent ten years at The Cadmus Group, where she supported U.S. Environmental Protection Agency contracts related to drinking water infrastructure, source water protection, climate resilience, and environmental health. She holds a bachelor’s degree from Williams College and a master’s of public health from the George Washington University. She is based in Washington, D.C.
A Decision Maker’s Guide to Valuating Coastal Resiliency
Mariah McBride, Coastal Systems International
As the climate changes and many coastal communities become more acquainted with the binding relationship between sea level rise and erosion rates, local decision makers are becoming progressively responsible for communicating the most advantageous plans of action. A solution that has effectively become known as standard practice for many seaside constituencies is that of beach nourishment, or the replenishment of sand in locations that have become deficient in natural sand source supply. There have been approximately 1.5 billion cubic yards of sand placed on the coastal United States through an accumulation of roughly 400 beach nourishment projects (NOAA, 2018). The sustainability of beach nourishment projects, the practicality of such projects in comparison to those less feasible, the aesthetic appeal of a broader beach, and the net benefit available to local property owners are among the many features that have proven the feasibility of beach nourishment. Yet, it is still imperative in many cases that decision makers aim to effectively communicate and present the cost-benefit of beach nourishment to local communities even when considering its many demonstrated successes. This could be attributed to factors including the sense of uncharted territory felt by communities that have only recently been faced with confronting the effects of beach erosion or the feeling of reluctance amongst community members that are uncertain of the prospective return on investment. Regional administrators who encourage this form of coastal zone management, including those experienced with the outcomes of beach nourishment and those who are not, are continually tasked with generating comprehensive material that accurately communicates the regional benefits of such an endeavor. Quantifying the economic benefits of beach nourishment is a topic that many economists have explored and several models have been accepted into practice. As many local decision-makers are aware of these recognized economic models, the variance between data outcomes based on the model selected for application is a topic less explored. For example, the hedonic model can be utilized to calculate the value of independent variables (ie varying beach widths adjacent to proportional single family homes) against a dependent variable (ie the total market price of each single family home) to determine property value enhancement of a wider beach in real-time. Alternatively, historic data can be adjusted for inflation and used for a comparative model in order to explain the economic implications of beach nourishment in a particular location over a period of time. A cost-benefit analysis model can be applied to rationalize the cost of beach nourishment and may be used as a tool to justify upfront costs. Understanding the variety of messages that can be generated by utilizing these economic models might be essential to effectively communicating the economic benefits associated with beach nourishment based on the values of a particular audience. The purpose of this report is to provide coastal zone managers with a framework that assists in distinguishing the various data outcomes that are accessible through the application of individual economic models and determining which methodology might be most relevant and impactful given the circumstances or ethics of a given audience.
Presenter Bio: Graduated valedictorian from Texas A&M University in 2018 with a Bachelor of Science in Maritime Public Policy and Communication and a double minor in Ocean & Coastal Resources and Geology. Awarded the Student Research Poster Presentation Award at the 2018 ASBPA Conference in Galveston, TX and was selected for the Academic Achievement Award at the 71st Annual Gulf and Caribbean Fisheries Institute Conference (2018) in San Andres, Columbia.
The Economics of Managed Retreat
Philip King, San Francisco State University
As adaptation planning proceeds on the coast, many plans/policies call for “managed retreat,” yet the actually management of this retreat is often unspecified. This paper addresses specific economic considerations that policy makers must consider when implementing managed retreat. The most politically fraught issues generally involve private landowners losing their land to erosion or “takings.” This loss of land and other property may or may not be compensated for. In many California communities, current sea-level rise and erosion predictions indicate that retreat is not necessary for twenty, thirty, or more years. In these cases policy-makers have choices to make. This paper presents one potential solution for many communities in California—a lease-buyback program. In a lease-buyback, a governmental, nongovernmental or private organization buys the property and leases it back (the current owner or tenant has first right of refusal) until a trigger point is reached and the property is abandoned. This paper examines such a solution in two California communities: Imperial Beach, and Pacifica. In some cases a subsidy may be needed, however if a lease-back is combined with other options, such as transfer of development rights, there may be no need for a pubic subsidy. This paper concludes by examining sources of public funding (from FEMA to local funding sources) as well as opportunities for private sector players (e.g., Airbnb) to become involved in the retreat process.
Presenter Bio: Dr. Philip King has been involved with the economic analysis of California’s beaches for over 20 years and sea level rise for over ten years. He has published numerous articles on the economics of beaches and climate change.
innovative Beach Stabilization Method
Amine Dahmani, University of Connecticut
It is increasingly clear that the acceleration and severity of beach erosion over the last sixty years is due in large part to sand dune destruction, longshore drift disruption, sea level rise and saltwater intrusion. An overlooked and underestimated contributor to coastal erosion is the change in the characteristics of sand brought through beach nourishment. Imported beach sand is non-cohesive and is easily eroded and suspended in water, even under moderate wave action. The imported sand can have other detrimental effects, such as impoverishing biotic diversity. Although serious efforts have been made to rebuild dunes, reestablish longshore drift and minimize windblown erosion, no measures have been taken to enhance sand retention on natural or nourished beaches. One potential solution to enhancing the physical and biological properties of sand is the use of natural biopolymers. The impact of natural biopolymers on sediment cohesion has been actively studied. The studies have demonstrated that extracellular organic secretions from microorganisms and microphytobenthos can coat sediment clasts and increase the cohesive nature of the sediment. The organic exudates (proteins and carbohydrates) enhance the cohesion of sediment, increase critical erosion velocity of intertidal sediment and result in higher erosion thresholds throughout periods of desiccation.
Proprietary protein polysaccharide biopolymer formulations (PPBs) have been developed by Dr. Dahmani. The product formulations are composed of natural polysaccharides and proteins. They are designed based on the characteristics of the site sand characteristics and water chemistry. One of the PPB formulations, SandFirst, was tested for a beach erosion mitigation application on a renourished beach in Mexico’s Yucatan peninsula. The SandFirst PPB solution was placed in the intertidal zone and the treatment results were monitored over a one-year period. The PPB solution was also used to minimize wind-blown erosion and stabilize sand dunes. Dry beach profiles and bathymetric profiles were obtained, and sand accretion/erosion were monitored for the PPB-treated beach section and compared to two similar untreated beach sections (controls) located east and west of the PPB-treated beach. Beach profiles were measured monthly for a year to assess the effectiveness of the PPB treatment in controlling beach erosion. The results showed that the erosion/accretion rate in the treated section was +0.06 m3/m indicating accretion, whereas in non-treated control sections, the rate was -4.04 m3/m, indicating erosion. The findings indicate that using PPBs is a promising eco-friendly method for enhancing beach retention by enhancing sand cohesion. One should note that the intent of the PPB treatment was to sufficiently enhance sand cohesion to minimize offshore transport of sand. During erosion cycles, sand from the intertidal beach area was transported to the near shore area and remained an available sand source during accretion cycles. Therefore, it is recommended that beach erosion mitigation methods include sand treatment in order to reduce the frequency of renourishment efforts. The benefits are three-fold: enhanced sand retention, minimization of the negative biotic impact of beach erosion, and reduction in the overall cost of beach erosion mitigation.
Presenter Bio: Dr. Dahmani obtained a Ph.D in Petroleum Engineering from LSU in 1986. After working in the oil industry for four years, he joined the University of Connecticut (UCONN) in 1990 to work on environmental remediation research and development. Dr. Dahmani joined in 2005 Spectrum Analytical (Eurofins) to head the remediation and petroleum forensics group. Dr. Dahmani is currently Associate Professor in Residence at the UCONN Civil & Environmental Engineering department and Senior Project Manager at SESI Consulting Engineers. He has worked for the last five years on innovative natural biopolymer technology to reduce beach erosion and stabilize contaminated sediment.
Monitoring Results of Beach Fill Project at Cape Shores, Delaware
Joseph Faries, DNREC
Co Authors: Jesse Hayden, Ashely Norton
In 2017, Aptim Coastal Planning & Engineering, Inc. (Aptim) prepared an evaluation of beach nourishment activities at the community of Cape Shores in Sussex County, Delaware for Delaware’s Department of Natural Resources and Environmental Control (DNREC). Cape Shores beach is a public beach on Delaware Bay that is located between the Cape Henlopen State Park to the east and the Cape May Lewes Ferry Terminal to the west. It is sheltered from ocean swell by the Cape, and harbor breakwaters but is exposed to energy from due north wind waves, which are common during the winter northeaster storm season. The evaluation summarized the volumes placed along Cape Shores since 1998, which had totaled 151,828 cubic yards-equating to approximately 8,000 cubic yards per year. Prior to 2008, Cape Shores had been solely responsible for the nourishment projects. In 2008, DNREC and Capes Shores entered a cost sharing agreement for nourishment occurring at a 5-year interval. The community has performed infusions of sand during interim years since this agreement. The grain size characteristics of sediment placed on the beach prior to the joint Cape Shores (Cape Shores and DNREC) 2008 nourishment had not been documented but evidence indicates that the sediment included a substantial fraction of silt owing to the near vertical face along dune escarpments. However, more recent nourishments utilized sand with a coarser median grain size which was more comparable with the native beach. Aptim recommended raising the elevation of the berm by 0.5 – 1.0’ to 7’ NAVD88 and the elevation of the dune to an elevation of 10’ NAVD88. Aptim further recommended that the nourishment be lengthened by 500 feet. During the fill project in the spring of 2018, 31,000 cubic yards were placed along 2,550 linear feet of beach at a rate of approximately 12 cubic yards per foot following recommendations in the evaluation prepared by Aptim. As-built profile surveys were collected using an RTK GPS rover system as well as a photogrammetric survey collected using an unmanned aerial system (UAS or drone). These survey results reveal that the constructed profile resulted in a berm that was 40’ wide with an elevation of roughly 7’ NAVD88 and a dune with an elevation of 9-10’ NAVD88, which essentially matched the recommended design.
As of May 2019 it has been roughly one year since the most recent nourishment at Cape Shores. A monitoring survey, using both the RTK GPS rover system and UAS have been conducted. These monitoring survey results are being compared to the as-built survey results. Calculations of profile change in terms of cubic yard loss and geometric assessments (berm dimensions, shape and dune profile) will be presented. Also, a comparison of these loss estimates and assessments amongst different survey methods and post processing methods – RTK GPS rover system using average end area – will be presented. These monitoring results will be discussed in the context of the project’s design goals. Recommendations for future monitoring surveys will also be made.
Presenter Bio: Joseph Faries is a coastal engineer in DNREC in the Division of Watershed Stewardship Shoreline and Waterway Management Section. Prior to this position, Mr. Faries has years of experience in floodplain modeling and mapping – and advancing the technical merit thereof. Mr. Faries has a bachelor’s degree in Civil and Environmental Engineering with a minor in economics and a master’s degree in Coastal Engineering all from the University of Delaware; he is passionate about applying his education and professional experience to enhance and protect Delaware’s coastal resources.
Vegetating Kill Devil Hills: Challenges of Planting Through Inclement Weather
Steve Mercer, Coastal Transplants Inc
Kill Devil Hills contracted Coastal Transplants to provide installation of 600,000 plants which has been completed over 18 months due to several weather occurrences interrupting working conditions. The beach re-nourishment planting project began in August 2017. Approximately 70,000 Sea Oats were installed in the Fall of 2017; 300,000 American Beach Grass were installed in the Winter of 2017-2018; 185,000 Sea Oats were installed in the Spring-Summer of 2018; and 60,000 Sea Oats will be installed in the Summer of 2019.
Four separate weather occurrences have impacted the project throughout the duration. First, a tropical storm in the Fall of 2017 lasting two days whipped plants in the elevated wind. Eleven inches of snow fell on the beach during the Winter of 2017-2018 followed by three Noreasters. Summer 2018 saw record high temperatures and draught. Finally, Florence hit the North Carolina coast in Fall 2018.
These weather challenges express the range of difficult and unpredictable conditions faced on the coast by vegetation. Challenges were overcome by replacement, increasing labor for efficient install, and application of fertilizer to boost growth of hearty plants.
The presentation will focus on project design and scope of work; explaining the unique challenges and how they were overcome; and lessons for future projects.
Presenter Bio: Steve Mercer, President, Coastal Transplants
Steve is President of Coastal Transplants, Inc. located in Bolivia, North Carolina. His many years of experience in growing and installing coastal vegetation has allowed him to expand his business along the Atlantic coast and in the state of Texas. The company currently grows and installs 500-700,000 warm season plants every year.
Dune Remediation – The Story of Tybee Island, Georgia
Alan Robertson, AWR Strategic Consulting
After more than a generation of avoiding the impact of hurricanes, Tybee Island, GA was hit with back-to-back “1 in 100 year” storms. Hurricane Mathew hit as a Category 3 in 2016 and Hurricane Irma hit as a Category 2 in 2017. Hurricanes Michael and Florence hit as Tropical Storms last year.
The impact was particularly significant since Tybee Island is a barrier island within the Savannah River Watershed, dealing with tidal interfaces and Sea Level Rise. The island is completely surrounded by Marsh on the back side, Atlantic Ocean on the front, and the mouth of the Savannah River to the north, with the deepened commercial shipping channel providing access to the Port of Savannah, the 4th largest container port in the U.S.
Because an effort had been undertaken to catalogue and assess all public access points to this resort town in early 2016, the City was in a position to respond to the damage done to its dune system. With the impetus of a State of Georgia grant last year specifically earmarked to restore and strengthen dunes and beaches, Tybee Island has embarked on a multi-year program of dune remediation. The first phase was completed April of this year. At approximately 20,000 cubic yards of sand, it is the largest project on the Georgia coast short of a full beach nourishment.
Alan Robertson is project manager for the program and will speak to the various elements of a project of this magnitude, including Assessment, Planning, Engineering, Contracting, Landscaping, City Authority, Regulatory Authority, and Public Relations.
Presenter Bio: Alan Robertson is Principal of AWR Strategic Consulting, a management consulting company. He was formerly Executive Vice President and Global Head of Sales and Marketing of a global financial institution. As a resident of Tybee Island and a member of the Tybee Island Beach Task Force, he developed an interest in shore and beach preservation. He is a member of the City’s Planning Commission and Chair of the City’s Master Plan Committee.
Developing Dynamic Boundary Conditions (surge+tide+sea level rise) for Stormwater Modeling
Chris Mack, AECOM
This presentation describes the approach for developing dynamic boundary conditions for a drainage analysis using ICPR for the City of Charleston, SC. The approach includes application of NOAA’s 2017 sea level rise estimates, synthetically derived storm surge hydrographs, and tidal phasing. Results demonstrate the vulnerability of drainage systems in low-lying flood plains. The approach also demonstrates a means to identify and prioritize future capital improvement within a drainage sytem.
Presenter Bio: Chris Mack has over 28 years of coastal engineering and water resource experience in the public and private sectors. This includes more than 13 years with the US Army Corps of Engineers (USACE) and 15 years with private coastal and marine engineering firms. Chris has academic degrees in Water Resources, Coastal, and Software Engineering from NCSU, College of Charleston, and the Citadel. He currently manages AECOM’s Coastal Services and a staff of coastal engineers and CAD/GIS technicians for coastal projects on the east coast of the US including NC and SC.
INNOVATIVE COMBINED COASTAL/INLAND FLOODING MODELS AND SOLUTIONS FOR USE IN COASTAL/ESTUARINE AREAS
Johnny Martin, Moffatt & Nichol
Co Authors: Johnny Martin, Katie Finegan
Many coastal/estuarine communities experience flooding due to low topography, a shallow groundwater table, rising water levels, and the lack of any drainage system. Historically, modeling of these systems depended on two separate models (one for coastal processes and one for inland/urban/riverine processes). New tools have come online that allow for these systems to be modeled and studied using one tool. These new models have given now a much higher level of confidence in being able to describe these environments as well as investigate potential solutions. The first part of this presentation will summarize the use and application of these new models. The second part of the presentation will describe numerous potential solutions for flooding in these complex environments to enhance community resilience. Solutions described will include green infrastructure, living shorelines and groundwater management systems. Real world applications and performance of these measures will be presented.
Presenter Bio: Johnny Martin has been serving as a Coastal/Hydraulic Engineer with Moffatt & Nichol for over 25 years. He received both a Bachelor of Science and a Master of Science degree in Civil Engineering with a concentration in Coastal Engineering/Water Resources from North Carolina State University. During his tenure at M&N, he has spent a majority of his time involved in both coastal engineering design and hydrologic and hydraulic modeling for projects on both US coasts and internationally.
Artificial Intelligence and its Applications to the Coastal Environment: Recent
Phillippe Tissot, Texas A&M University-Corpus Christi
The field of Artificial Intelligence (AI), including its application to environmental science, has grown substantially over the past few years. The presentation will start with a historical perspective of the growth of AI starting in the mid 80’s and the change in the AI methods used to tackle environmental problems. A brief overview of three widely used AI methods, shallow neural networks, random forest and deep learning will be presented followed by their application to coastal problems, including the implementation of operational AI based models. The respective advantages of the methods and their applications will be discussed. Other past and recent coastal applications will be briefly mentioned. The presentation will conclude with a discussion of some of the present research questions such as the quantification of uncertainties, interpretability, incorporating domain-knowledge in model design and the potential for AI applications to the coastal environment.
Presenter Bio: Philippe Tissot is the interim Director for the Conrad Blucher Institute and an Associate Research Professor at Texas A&M University-Corpus Christi. His research is focused on the development of artificial intelligence methods for the prediction and analysis of environmental systems and the analysis and prediction of coastal processes. Studies have included the modeling and impact of relative sea level rise, subsidence and storm surge at the regional scale, the development and implementation of predictive models supporting navigation and coastal management, tidal studies and local hydrodynamic models. Ongoing projects include studies of the spatial variability of relative sea level rise, the application of clustering algorithms to 3D point clouds of marsh environments and urban runoff water quality modeling. Professor Tissot is presently the chair of the American Meteorological Society Committee on Artificial Intelligence Applications to Environmental Science.
The South Carolina Floodwater Commission: A call to action in a changing world.
Will Ambrose, Coastal Carolina University
Co Authors: Tom Mullikin
Our nations coastal regions have long served to attract and support a growing population, infrastructure and economy. Like many coastal states, the state of South Carolina has been experiencing rapid growth in the coastal zone and the associated challenges of balancing sustained coastal resource-based economies and lifestyles within a dynamic environment shaped by episodic but highly energetic events such as storms. Over the last decade, South Carolina has weathered a series of historic flood events causing widespread damage and disruptions to citizens, communities and the state as a whole. Many communities are still working to recover for an individual or series of recent flood events.
Governor Henry McMaster established the South Carolina Floodwater Commission, drawing from a diverse array of expertise and experience to consider the nature of and challenges from repeated flooding events across the state. The Commission is tasked to consider the near- and long-term needs with a focus on areas of most significant impact along the immediate coast and broader statewide drainage network. The Commission is to compile and assimilate state-of-art knowledge and work towards an innovative state-wide flood accommodation, response and mitigation effort to safeguard our communities and state that is so dependent on the dynamic coastal environment. The overall goal is to render the state, its citizens, economy and environment more resilient and safeguarded from episodic flood events in a dynamic environmental and human landscape.
The scope and breadth of flooding issues facing the state are diverse and complex. The temporal and spatial scales of flooding pressures being faced may also lead to different near- and long-term strategies. The Commission established, and charged, multiple Task Forces to consider key areas of concern and to facilitate interaction of all levels of government, private and academic resources towards recommendating courses of action to reduce and help mitigate impacts or flooding. This structure recognizes there are critical interrelationships and need to coordinate across and between various areas of focus to address the need and charge from the Governor. The individual Task Forces include: Smart River and Dam Security, Infrastructure and Armoring Shorelines, Living Shorelines, Grid Security, National Security, Stakeholder Engagement, Federal Funding, Economic Development and Artificial Reef Systems.
The South Carolina Floodwater Commission held its inaugural organizational meeting in December, 2018 and subsequently quarterly meetings are scheduled through 2019. Individual Task Forces are working on an aggressive schedule and are to generate an initial draft report in June 2019. All meetings are open to the public.
The Theme Session will provide an overview of the Commission with presentations by some of the task forces most aligned with the “Where Rivers Meet the Coast” theme of the Conference. Information on the Commission may be found at https://governor.sc.gov/executive-branch/south-carolina-floodwater-commission.
Presenter Bio: Dr. Ambrose is Vice-Dean of the School for the Coastal Environment and Professor of Coastal Marine Systems Science at Coastal Carolina University. He studies processes influencing the structure and function of marine communities. He is an Arctic scientist with an extensive research career in Arctic benthic ecology, Arctic environmental change, and Traditional Scientific Knowledge. Before Coastal Carolina University, Dr. Ambrose was at East Carolina University, Bates College, the University of Oslo, the University of Tromsö, and the National Science Foundation.
The South Carolina Floodwater Commission – The Living Shorelines Task Force: A call to action in a changing world
Paul Gayes, Coastal Carolina University
Co Authors: Nicole Elko
The South Carolina Flood Water Commission was established to assemble public, private and academic capacities towards enhancing the resiliency and mitigate negative effects of recurrent flooding in the region. Governor Henry McMaster established the Commission in response to a series of flooding events that severely impacted property, citizens and economies across the state over the last several years.
The Commission was organized into Task Forces to examine the diverse drivers and needs related to flooding and to recommend potential courses of action to reduce future flooding events. This is to considers the complexity and challenges in the near- and long- terms within a dynamic and evolving natural and human landscape.
One Task Force was assigned to consider the potential role of Living Shorelines (LSL) in reducing flood impacts in South Carolina. LSLs are engineered to initiate, or re-establish the functionality of naturally occurring habitats resistant to erosional pressures. Traditionally they have focused on simulating oyster reefs or vegetative binding of fine-grained sediment which serves reduce sediment erosion from wave and current forces. In addition, these structures hold potential to reclaim or enhance important ecosystem services that may have been degraded or lost over time.
Most LSL applications in South Carolina have been confined to estuarine settings. A range of organizations such as SC DNR, SC DHEC-OCRM, The Nature Conservancy, Audubon Society and others have been evaluating past constructions as well as experimenting with LSL’s across the state. The efforts have also been on the scale of an individual properties and a summary of a recent experiment by state agencies and partners on LSL effectiveness within different estuarine habitat conditions is nearing completion. This is to lead to initial guidance towards optimizing living shoreline technology and applications as well as begin best practices in design and evaluation and result in a streamlined permitting process for these applications.
The Task Force is also considering the potential for larger community-scale applications of present LSL technology as well as potential application in non-estuarine shorelines. For example, river flood plains and storm water retention ponds represent vulnerable areas and already play an important role in flood mitigation and ecosystem services for the state. These are areas where the LSL concepts developed in estuarine settings may hold potential in scaling up to contribute to the overall goal of mitigating flood damage and impacts across a broader swath of the state.
Coastal states face a growing human landscape expanding within and towards coastal and shallow marine environments being driven landwards by a rising sea. This conflict is greatly amplified episodically during surge and flooding events extending the point of conflict much further inland and laterally. The record of recurring and increased damage and disruption is spurring a call to action. Interests in optimizing the dual role of LSL for flood mitigation and reduction as well as habitat and environmental services is being considered and will contribute to the developing State Floodwater Commission report.
Presenter Bio: Paul T Gayes is the Executive Director of the Burroughs and Chapin Center for Marine and Wetland Studies at Coastal Carolina University. He is serving as Chair of the Living Shorelines Task Force of the South Carolina Flood Commission
South Carolina (SC) Governor H. J. McMaster’s Smart River Task Force and the Charge to the Sub-Committee on Smart Rivers
Len Pietrafesa, Coastal Carolina University
From 2015 through 2018, South Carolina (SC) experienced four wet hurricanes that deluged the state in flooding from the coast to the mountains. The floods occurred over periods of hours to days to several weeks. Flooding scenarios literally reached from the coast to inland to upland areas for the same events. Unfortunately, the floods were poorly forecast by most, and lives were lost and property destroyed. Moreover, rising coastal sea levels have created what is termed “nuisance flooding” events along the SC coast during higher high tides. In December 2018, SC Governor J. H. McMaster convened a meeting and commissioned a Team of State, Federal, Industry and Academic Flood experts to address the entire issue of statewide flooding. The Smart River Task Force Sub-Committee (SRSC) is charged with studying and recommending various kinds of numerical modeling architectures that should be adopted or developed for SC during periods of flooding. The SRSC is also considering higher high tides and tsunamis. Finally, flooding and standing waters can create public health issues and these will be described. The real-time expected flood modeling prognostications, per se, are expected to cover periods prior to the arrival of a storm and during and following the storm’s passage and on incoming offshore water events. The intention is to provide visualized, validated model guidance to emergency managers and decision makers, up to the Office of the Governor, for informed planning and evacuation scenarios to save lives and property of residents of SC. The talk will cover:
What is required in the Modeling Enterprise is Proof of Application of the various Models and Model Systems under prior well-documented storm events such as Hurricanes Joachim (2015), Matthew (2016), Irma (2017), Florence and Michael (2018). One size does not fit all.
Presenter Bio: Len Pietrafesa is a Burroughs and Chapin Research Scholar in the Center for Marine and Wetland Studies at Coastal Carolina. He is retired Professor Emeritus from North Carolina State University and a former chair of NOAA’s Science Advisory Board.
Living Shorelines for Reducing Tidal Flood Risk and Protecting Live Oaks
Rod Tyler, Green Horizons Environmental LLC
Increased sea level rise has and will continue to encroach on live oak and other species, even normal landscapes. Communities built 20-30 years ago are now starting to experience increased river heights from the Waccamaw river as lunar and king tides prevent the river from fully emptying out each day or after severe rainfall. Recently, hurricanes that flooded rivers in low country areas all the way into North Carolina caused severe flooding of properties in Pawleys Island, SC. There are few guarantees with any tools or designs utilized to try to help prevent constant, monthly flooding especially during high water events from storm surges. However, the daily weekly and monthly use of properties can be made more functional by increasing the property height using a bulkhead or living shoreline system.
The low country area in the general Carolinas region is characterized by shorelines mixed with inlets, rivers, estuaries and floodplain. As development has occurred over time, the efforts to try to keep the historic and majestic live oak trees rather than remove them for development has created some extremely incredible specimens. Living shorelines, as options compared to vinyl, steel, or a wooden bulkhead, includes many beneficial cultural criteria that help the live oaks have a better chance for survival. Although this is not the single driver to choose living shorelines in many situations, property owners realize the historical and beautification benefits of keeping live oaks healthy.
The living shoreline system allows for water to be held back for most events when designed properly. The properties discussed in this presentation typically had 1-2 feet of water in the property during monthly high tides. The living shoreline has prevented this occurrence, thereby making the property more functional. When a 300 year-old historic live oak is lost due to constant flooded conditions, an obvious loss in property value occurs, not to mention aesthetic value.
Other applications for these types of designs should be considered all around the low country, where water meets land. Due to issues with bulkheads, which include cavitation after severe storm events, holding of water which is unhealthy for plant life behind the flooded wall and inability to establish vegetation, the living shorelines are becoming a more popular option. Living shorelines are able to breath compared to solid bulkheads. The costs to establish a Living shoreline are typically 30-50% less than typical bulkhead options. This cost saving, for existing property owners, allows a solution while maintaining the ability to keep native vegetation growing on, in and through the living shoreline system.
Presenter Bio: Rod Tyler is a graduate of The Ohio State University, a Certified Professional Agronomist, and has been working with compost and environmental projects for nearly 30 years. He is currently President of Green Horizons Environmental, a firm that built Filtrexx International, LLC. Green Horizons designs, specifies and installs Living Shoreline systems developed from 30 years of experience in the field. As founder of Filtrexx International, Rod is also the inventor of the patented SiltSoxx technology. Rod has written extensively including two books, hundreds of industry articles and research papers. Rod has been an invited speaker at previous American Shore & Beach Preservation Association and Restore America’s Estuaries conferences.
Developing a List of Approved Equivalent Living Shoreline Products in Coastal Louisiana
Casey Connor, Mott MacDonald
Co Authors: Josh Carter, Micaela Coner, Tye Fitzgerald
In 2017, the Louisiana Coastal Protection and Restoration Authority began the engineering phase of the PO-0174 Biloxi Marsh Living Shoreline Project which intends to place 9 to 11 miles of nearshore breakwaters. The project seeks to build upon the knowledge base developed during the previous phase where three artificial oyster reef products including Reef Ball™, Wave Attenuation Devices (WAD®), and OysterBreak™ were installed in nearshore breakwater configuration for approximately 1-mile increments. A series of wave gauges were deployed during the winter of 2017 to determine the effectiveness of each product at reducing wave energy. Analysis was performed to develop wave transmission coefficients for each product as well as validate the previous 2D-V and 3D computational tools. Performance goals were defined and became the basis of an alternative product solicitation.
The public solicitation will allow living shoreline product manufacturers to submit proposed products for evaluation on the project. The motivation of the solicitation is to use a fair, objective, market-based method for developing a list of approved equivalent products for the project. The solicitation establishes the framework for product manufacturers to submit products for the project and outlines the site-specific data including bathymetry, hazards, tide range, hurricane and design conditions, and geotechnical data. The solicitation also specifies the minimum required information to be submitted including background information (e.g. manufacturer name and location, product geometry information, manufacturing and installation procedures, and similar), breakwater bearing pressure calculations, and previous project references. The evaluation criteria and methodology, required deliverables, anticipated schedule, conditions, and similar information included within typical public solicitations is also discussed.
The evaluation of the submitted products includes evaluation of bearing pressures, stability during a Category 1 Hurricane, and ability to attenuate waves under conditions which typically drive shoreline erosion. The performance evaluation will be performed using the same 2D-V and 3D computation tools used to determine performance goals of the project. Products that fail to meet the minimum requirements or cannot meet project site conditions will be removed from further consideration on the project.
Products meeting the minimum requirements will be placed on a preliminary list of approved equivalent products. Detailed engineering and alternative analyses will be performed to maximize the overall performance for the project site as well as finalize construction details and specifications. A final list of approved equivalent products will be developed and included in the for bid documents for public bidding by prospective contractors.
Submittals were due on April 26, 2019, with the evaluation and development of the preliminary list of approved equivalent products anticipated to be completed by July 2019.
Presenter Bio: Mr. Connor is a Principal Coastal Engineer at Mott MacDonald located in Jacksonville, FL. He obtained his Bachelor of Science degree in Ocean Engineering from Florida Institute of Technology in 2005, and holds Professional Engineering licenses in Florida and Texas. His experience includes the full spectrum of project evolution from data collection, damage assessments, analysis, permitting, design, specification development, to construction engineering and inspection. His project experience includes beach and dune nourishment, living shorelines, revetments, breakwaters, groins, dredging, beneficial use of dredge material, boat ramps, and coastal vegetation.
Recommendations for a Sediment Diversion and Reconnecting a River to its Delta
Rachel Rhode, Environmental Defense Fund
Co Authors: Natalie Snider
Sediment diversions are currently one of the most talked about and most controversial restoration tools being considered to build and sustain coastal wetlands. A series of sediment diversions are being proposed to reconnect the Mississippi River to bring it sediment rich waters to sediment-starved, eroding deltaic wetlands. If operated effectively, they will mimic and restore the natural processes of a riverine system and provide a regular supply of sediment and fresh water to wetlands. Sediment diversions, in conjunction with other restoration project types, hold promise for achieving landscape scale restoration of wetlands and stave off rapid habitat loss that threatens coastal Louisiana.
Currently, the Coastal Protection and Restoration Authority (CPRA) is tackling engineering and design questions concerning the size, location and type of structure of the first sediment diversion as well as modeling questions such as anticipated ecological, social and natural resources outcomes. The decisions about how a diversion will be operated will be very important not just for the near-term allowing the system and communities to adjust to changes in salinity, water level and habitat, but the long-term as well in order to build elevation and allow vegetation to establish.
To acquire a construction permit, CPRA will have to provide an Operation and Adaptive Management Plan that defines how, when and why the diversion structure will be opened and closed, what factors will be considered, what monitoring is required, what governance will be used to oversee these decisions, and what role stakeholders will play in the decision-making process. Seeing a need for forming an external group to tackle the difficult questions surrounding diversion operations, Environmental Defense Fund (EDF), in coordination with Restore the Mississippi River Delta coalition partners, formed a Sediment Diversion Operations Expert Working Group (WG) to tackle these complex topics. The group developed and shared operation recommendations with CPRA, the U.S. Army Corps of Engineers (USACE), other state and Federal agencies, the larger scientific community and concerned stakeholders.
Over the course of eight months, EDF worked with the WG to explore, discuss, debate and document complex issues related to operating a sediment diversion. The working group met monthly to discuss specific topics of importance to diversion operations by using the Mid-Barataria Sediment Diversion as a case study. With each topic the team considered the state of the knowledge, trigger points, monitoring needs, potential data gaps, and how the issue would be affected by various methods of operation. The group then developed recommendations for how best to operate a diversion based on discussion of that theme. This included initially operating with a gradual increase over 5 to 10 years to help develop a distributary channel network, reduce risks of flooding to adjacent communities and reduce stress to fish and wildlife species. We found that capturing the highest sediment concentration, requires operating over winter peaks so as to reduce impacts to vegetation. Shorter operations in the spring/summer and rising limb of the river will result in highest sediment capture with lessening impacts.
Presenter Bio: Rachel is an Analyst on the Coastal Projects & Programs team for EDF’s Mississippi River Delta Restoration program. She is also the science and projects team coordinator for Restore the Mississippi River Delta. In this capacity, she reviews scientific literature for the latest research and tracks coastal restoration projects in Louisiana to identify challenges and barriers in project implementation and develop strategies and solutions to overcome. Rachel received both her BA and Master’s Degree in Marine Science and did her thesis work on river diversions and wetland loss in the Mississippi River Delta and their associated effects on oysters.
Atchafalaya River Freshwater Diversion – Restoring the Connection Between Coastal Plain and River
Kevin Hanegan, Moffatt & Nichol
Co Authors: Maarten Kluijver
Freshwater and sediment in the Atchafalaya River, in southern Louisiana, are currently confined to the leveed river until released south of Morgan City into the Atchafalaya Bay. Confinement of the river, in combination with high rates of subsidence and rising seas, has resulted in salt water intrusion and marsh degradation in the adjoining coastal wetlands. The Increase Atchafalaya Flow to Terrebonne Project was proposed to utilize freshwater and sediment from the Atchafalaya River to build, sustain, and maintain wetlands in the sediment-starved deltaic basin to the east of the river’s levee. A key component of the project is a 15,000 cfs freshwater diversion intended to hydrologically influence 500,000 acres of wetlands and slow the current wetland loss in the basin.
To determine project feasibility and screen initial project features, Moffatt & Nichol developed a coupled hydrodynamic, salinity, and Wetland Morphology (WM) model for the comparison of project alternatives. Encompassing the Lower Atchafalaya River and the surrounding Terrebonne Basin estuary, the model is used to calculate the long-term effects of alternatives on salinity propagation throughout the Terrebonne wetlands, as indicated by changes in vegetation, land cover, and open water. The WM module is dynamically coupled with a 2D hydrodynamic model and is used to evaluate the evolution of marsh types over 50-year timespan under the stressors of hydro-period and salinity on a high-resolution scale. A series of model runs using the WM module was used to establish the required diversion capacity and necessary project components to achieve projected Land Loss Prevention (LLP) benefits.
The authors present an overview of the most recent project modeling analysis, focused on determining the impacts of the project on sediment transport, erosion, and sedimentation. The existing basin-wide model was extended to include the advection-dispersion of fine sediments, where the high fine suspended load from the Atchafalaya River is distributed to the surrounding basin and coast. The model results indicate an increase in suspended sediment concentrations transported to the central Terrebonne marshes during operation of the diversion over three representative years and illustrate the nonlinear relationship between river discharge and sediment load. The effect of the proposed diversion on the basin-wide fine Suspended Sediment Concentration (SSC) is highly contingent on the Atchafalaya River flow conditions. The IAF diversion restores the riverine connection to the coastal wetlands in the Terrebonne Basin and increases influence, especially during low flow years.
During high flows, the fine SSC throughout the basin reflects the high load in the Atchafalaya River and the far-reaching influence of riverine freshwater routed into the basin through existing flow pathways. During low flows, fine SSC in the central basin is less influenced by the river.
While the project is advanced into Engineering and Design phases, continued modeling analysis has shifted from demonstrating feasibility to resolving project impacts and effects. An additional high-resolution morphology model, nested within the basin-wide modeling platform, has been developed to determine project impacts on erosion and sedimentation within the heavily-used Gulf Intracoastal Waterway (GIWW) navigation channel and inform diversion channel and structure design.
Presenter Bio: Kevin Hanegan is a practicing coastal engineer with Moffatt & Nichol in New Orleans. He holds a BS in Civil Engineering from LSU and an MSc in Coastal Engineering from TU Delft. He is currently pursuing a PhD in coastal hydrodynamics and morphology from the University of New Orleans.
COASTAL FORESTS AT THE CROSSROAD – CASE STUDY: LOUISIANA’S MAUREPAS SWAMP
Honora Buras, Louisiana Coastal Protection and Restoration Authority
Coastal wetland forests are often found at the intersection of estuarine tidal zones and the floodplains of rivers and streams that drain the interior uplands. These freshwater habitats are especially vulnerable to increased saltwater intrusion from sea level rise, subsidence, and land loss of adjacent marshes. They also face threats of conversion through unsustainable logging practices, development, and hydrological alterations. Rising seas will necessitate inland migration of habitats and people from the coast. Climate change has also increased the flashiness of river flooding, highlighting the importance of these forested areas for floodwater storage as well as habitat. Baldcypress swamps are important storm surge buffers and are some of the most resistant trees to wind-throw from tropical storms and hurricanes. Conservation and restoration of these forests for the multiple ecosystem services they provide is an important part of floodplain management.
The Maurepas Swamp is located at a critical juncture of numerous small rivers and the estuarine habitats of coastal Louisiana. It is the second largest contiguous coastal forest in Louisiana, comprised of 77,500 ha of baldcypress/ water tupelo swamp between New Orleans and Baton Rouge. For centuries it has provided innumerable benefits to people in addition to its significant habitat value. Considering the location of the Maurepas Swamp in relation to several major population centers and important industries with no hurricane levees to protect them from storm surge, it is vital that the Maurepas Swamp is able to continue protecting these communities and assets.
The Louisiana Coastal Protection and Restoration Authority (CPRA), along with many other agencies and NGOs have made a priority of saving the Maurepas Swamp while it is still possible. Severed from its natural connection to the Mississippi River through levee construction and closure of Bayou Manchac over 200 years ago, the forest no longer receives throughput of freshwater, nutrients, and sediments except through small rivers and other nonpoint sources of stormwater runoff. Due to this and other factors, the majority of the swamp is rapidly declining and converting to marsh and open water.
There are many components of a comprehensive, basin-wide strategy for conservation and restoration of the Maurepas Swamp ecosystem, primarily through land acquisition, planting, and reintroduction of the Mississippi River through controlled freshwater diversions. CPRA is in the final stages of engineering and design of a river reintroduction project at Hope Canal, integrating it with the planned West Shore Lake Pontchartrain Hurricane Protection Levee. The major floods in 2016 of the basin’s rivers have triggered additional emphasis on integrating regional floodplain management of Louisiana’s rivers with coastal protection through the Louisiana Watershed Initiative.
Much of the area is open to the public for recreational use as a State Park and two Wildlife Management Areas which have recently been expanded through major land acquisitions through CPRA’s Coastal Forest Conservation Initiative and other programs.
This presentation will highlight the relationship between people and the Maurepas Swamp – its historical significance, causes of decline, numerous ecosystem services it provides, and an overview of various restoration, protection, and conservation activities.
Presenter Bio: Ms. Buras is a senior coastal resources scientist, botanist, and Master Naturalist with more than 20 years of experience planning, and implementing coastal restoration and protection, community resilience, and forest conservation projects and programs. She also has extensive additional experience promoting green infrastructure and educating the public on native plants and the natural resources of south Louisiana.
Coastal Resiliency Planning: Defining & Moving Towards Resilience on the Coast
Chris Levitz, AECOM
Co Authors: Taylor Nordstrom, Joshua Oyer
One of the focuses of the 2019 Texas Coastal Resiliency Master Plan (Resiliency Plan) is to accurately and realistically describe possible future scenarios on the coast related to expected climate- and environment-related changes. Quantifying and characterizing these changes are critical for planning coastal projects and ensuring that state funds are used strategically and effectually to benefit coastal resilience. To achieve this, the Texas General Land Office (GLO) has defined what the state considers ‘resiliency’ to entail, as well as steps that are currently underway or planned for the future that can help the GLO achieve greater levels of resilience. The first step in this process is understanding why resiliency is needed (for instance, due to what physical or environmental processes) and where the largest or most pressing areas of need exist. Although a long-term planning effort, the Resiliency Plan considers short-term vulnerabilities, such as those driven by coastal storms, as well as long-term vulnerabilities, such as sea level rise.
Specific to the 2019 planning process, the GLO developed a series of recommendations for relative sea level rise planning estimates to be used along the Texas coast when implementing resiliency projects. This presentation will describe at a high level some of the coastal modeling that was used to identify future vulnerabilities of land loss, storm surge inundation, and economic damages due to storm-induced flooding—all including the potential future effects of sea level rise—focusing on the practical implementation of these results. Building knowledge of future conditions allows the Resiliency Plan to promote proactive measures rather than traditional reactive efforts, creating greater possibilities for cost-efficient programs that have significant long-term benefits. The presentation will also discuss how resiliency is incorporated into program-level project recommendations and other prioritized ‘Tier 1’ projects presented in the Resiliency Plan.
The GLO has identified several areas of growth to continue to make the Resiliency Plan a useful tool for project managers overseeing project implementation using funds provided or administered by the GLO. Included in this goal are developing templates and standard operations to assist the GLO and interested coastal stakeholders in designing and constructing more resilient projects under the umbrella of adaptive management. It also includes helping progress prioritized, but highly conceptual coastal resilience projects into initial design and permitting phases. From a data collecting and monitoring standpoint, improving models that characterize “future with-project” scenarios at mitigating the effects of sea level rise will give additional justification for project construction and provide tangible goals for how projects should incorporate the predictions generated by these models during design.
The GLO coordinates its resiliency planning efforts with a wide array of coastal stakeholders. Part of the GLO’s focus on resilience includes fostering open communication and provide useful tools to improve how the coast is managed across diverse perspectives. From a stakeholder and community engagement standpoint, the GLO is developing enhanced coastal hazard mapping tools to better inform local coastal management and development planning, among other ongoing outreach and coordination activities.
Presenter Bio: Mr. Levitz is the coastal engineering and resiliency manager for the Gulf Coast at AECOM. He and his team specialize in restoration and resiliency design along the coast, with particular expertise in large-scale planning efforts and consensus building.
Climate Change: Facts, Fables, and Fanaticism
Chris Mack, AECOM
Most people today agree that climate change is occurring (i.e., it’s real). Controversy abounds regarding climate change cause-n-effect (i.e., it’s us). Is it “the Boy who Cried Wolf” or must something be done today (i.e., it’s urgent)? This presentation provides a topical summary of today’s climate change threats and trends, the facts and fables with empirical and modeled predictions, and a brief look at the antagonist and protagonist headlines leading the global debate.
Presenter Bio: Chris Mack has over 28 years of coastal engineering and water resource experience in the public and private sectors. This includes more than 13 years with the US Army Corps of Engineers (USACE) and 15 years with private coastal and marine engineering firms. Chris has academic degrees in Water Resources, Coastal, and Software Engineering from NCSU, College of Charleston, and the Citadel. He currently manages AECOM’s Coastal Services and a staff of coastal engineers and CAD/GIS technicians for coastal projects on the east coast of the US including NC and SC.
Implementing Nature-Based Solutions for Coastal Highway Resilience
Bret Webb, University of South Alabama
Co Authors: Bret Webb
There are over 60,000 miles of coastal highways in the United States exposed to, or occasionally exposed to, storm surge, waves, and erosion. These coastal highways, consisting of roads, bridges, tunnels, and their associated drainage infrastructure are vulnerable to extreme events today. Those vulnerabilities may increase over time as sea levels rise. Strategies for improving the resilience of coastal highways today can lead to enhanced resilience to future changing ocean and weather conditions. Such strategies include, either individually or in combinations: policy, structural, natural, and nature-based solutions. Combining traditional engineering (i.e., structural) approaches with nature-based solutions offer risk reduction benefits across a wide range of event frequencies and magnitudes, while simultaneously providing co-benefits such as water quality improvements, habitat enhancements, and opportunities for recreation and education. However, transportation professionals operating across the spectrum of project delivery (e.g., planners, scientists, engineers, maintenance staff) lack guidance on the implementation of nature-based solutions—marshes, mangroves, maritime forests, reefs, beaches, and dunes—when considering design, repair, restoration, or resilience alternatives for their infrastructure. The United States Department of Transportation Federal Highway Administration has developed an Implementation Guide for Nature-Based Solutions that seeks to address this and other barriers to implementation. The guide is organized into chapters that sequentially follow the transportation project delivery cycle. The benefits and typical costs of nature-based solutions are described first, followed by chapters on planning and funding; site characterization; design considerations; permitting; construction; and monitoring and maintenance. The goal of this guide is to provide transportation organizations (e.g., state departments of transportation, metropolitan planning organizations, regional transportation authorities, and others) with relevant and timely information to aid in the implementation of nature-based solutions for coastal highways.
Presenter Bio: Bret Webb is a Professor of Coastal Engineering at the University of South Alabama. Dr. Webb’s research interests fall within the broad topic of coastal resilience. His current research focuses on two different aspects of coastal resilience: resilience of the built environment to extreme events, and how that resilience is enhanced through the use of natural and nature-based features. Bret is currently working on a few nationwide projects related to natural and nature-based features, like living shorelines, and is also co-editor of an upcoming book on living shorelines. In addition to Bret’s research at USA, he is also a registered professional engineer (AL, FL) and often consults on living shoreline and other coastal engineering projects. Bret is also endorsed by the Academy of Coastal, Ocean, Port, and Navigation Engineers as a Board Certified Coastal Engineer.
Coastal Resiliency Planning: Managing Resiliency from a State Agency Perspective
Josh Oyer, Texas General Land Office
Co Authors: Chris Levitz, Taylor Nordstrom
This presentation will give an overview of the 2019 Texas Coastal Resiliency Master Plan (Resiliency Plan)—the Texas General Land Office’s (GLO’s) comprehensive, statewide plan to improve the Texas coast by identifying large-scale needs that “tell the story” of the current state of the coast and drilling down to individual project-level identification and implementation. The current version of the Texas Coastal Resiliency Master Plan was published in March 2019 and is the second iteration of the GLO’s Resiliency Plan. The presentation will describe the GLO’s future vision for coastal resiliency now through the next iteration of the Resiliency Plan in 2023.
Through more than seven years of statewide coastal resiliency planning, the GLO has developed a framework to assess coastal vulnerabilities for both current and future conditions, identify priority projects, and integrate the Resiliency Plan into funding streams available for project implementation. Within this broader framework, the methods the GLO has created range from a programmatic model, used to systematically sort and filter projects related to coastal resiliency, to repeatable stakeholder engagement processes, used to create meaningful discussions and elicit project evaluations from the GLO’s Technical Advisory Committee (a group of over 200 coastal experts from a variety of coastal-related disciplines). Specific to the 2019 planning process, the GLO developed a list of 123 prioritized ‘Tier 1’ projects recommended for implementation to increase Texas coastal resiliency.
Future expected enhancements to the Resiliency Plan include: better detailing out the practical application of resiliency concepts (such as mitigating risks from relative sea level rise) to prioritized projects and progressing the projects through design, permitting, and construction or implementation phases. The prioritized projects in the Resiliency Plan include a wide range of solutions, including beach nourishment, living shorelines, wetland restoration, shoreline stabilization, improving evacuation routes, creating additional storm surge protection levees, and making policy and program-level improvements.
As a state agency, the GLO also coordinates closely with its federal partners on ongoing federal studies, such as the U.S. Army Corps of Engineers’ comprehensive storm risk management study for storm surge protection and ecosystem restoration, known as the Coastal Texas Study. This presentation will explain how the Texas Coastal Resiliency Master Plan collaborates with this study, and other large-scale plans on the Gulf Coast. It will touch on how the Resiliency Plan integrates academic research, state and federal agency priorities, and local expertise to create a robust and achievable vision for statewide resilience to coastal storms and other vulnerabilities (such as lack of freshwater inflows, habitat degradation, and flooding, to name a few).
The presentation will be of particular interest to anyone who is involved with large-scale planning in coastal environments, including multi-agency and stakeholder coordination. It will describe lessons learned related to coastal resilience, master planning, consensus building, outreach, and project implementation through a state agency point-of-view.
Presenter Bio: Josh works with the Texas General Land Office in the Coastal Resources Division as a Planner focused on the ongoing coordination of the Texas Coastal Resiliency Master Plan. Previous to holding this position, he was a part of the Land Office’s Beach Access and Dune Protection Program dealing with enforcement of the state’s Open Beaches Act and Dune Protection Act. He has also held positions in education and outreach roles with the Texas Water Development Board, Texas Parks and Wildlife Department, and Texas State University – San Marcos.
Tracing Study into Beneficial Use of Dredge Material on a Nearshore Berm, South Padre Island, Texas
Kristina Boburka, City of South Padre Island
Co Authors: Patrick Friend
The interest in gaining a wider and better understanding of how sediment moves within an active beach profile has grown increasingly throughout the years. Nearshore berms have been used as placement areas for dredged material in shoreline management plans, but empirical data are lacking on the behavior of these berms. Results are reported for a sediment tracing and berm monitoring study after a nearshore berm was constructed roughly a half mile off shore. The data are required to monitor the existing sediment transport models and to better predict the sediment movement onshore from the berm to the beach.
Material placed on nearshore berms to modify the onshore beach profile has been practiced since the 1970s. The United States started extensively researching this idea in the 1980s with the intention of altering the beach profile and attenuating waves and moving sediment onshore (Burke et al, 1991). The idea of ‘feeder’ berms have been studied more recently in Ocean Beach, California, as well as in Fort Meyers, Florida (Brutsche and Wang, 2011). In Ocean Beach, sediment was transported onshore from large waves during the 2006-2007 winter, but it is unclear of whether this was related to the berm (Barnard et al., 2009). With onshore beach nourishment from Beneficial Use of Dredge Material (BUDM) being cost-intensive, interest in placing material onto nearshore berms has grown because of its cost efficiency.
The Beneficial Use Nearshore Berm Tracing study at South Padre Island, Texas, took advantage of an emergency dredging event by the US Army Corps of Engineers to remove material from the Brazos Island Harbor entrance channel. The material was used to construct a nearshore berm in water approximately 30 ft. deep and in the Placement Area 2 off South Padre Island. Nearshore berm placements have taken place at South Padre Island since 1988, when material was placed in Placement Area 1. Monitoring has shown that material moves towards the beach with major dispersal in an alongshore direction. This study is working to obtain a detailed understanding of how the sediment moves within the coastal system so we can better manage our beaches on South Padre Island.
Presenter Bio: Kristina Boburka earned her B.S. in Biology from Saint Vincent College in Pittsburgh, PA and then her M.S. in Marine Biology, with a GIS Certificate at Texas A&M University at Galveston. Her work in graduate school was focused on utilizing GIS and modeling to study the impacts sea level rise may have on the nesting habit of Kemp’s Ridley sea turtles along the Texas Coast. Kristina now works for the City of South Padre Island in the Shoreline Department applying her education to better manage the beach and natural resources on South Padre Island.
A numerical model analysis of potential shoaling rate changes due to the Corpus Christi Ship Channel Improvement Project
Gary Brown, US Army Corps Of Engineers, Engineer Research and Development Center
Co Authors: Mohammad Islam, Corragio Maglio, Thomas White
The U.S. Army Corps of Engineers Galveston District (SWG) is currently engaged in the deepening of the Corpus Christi Ship Channel (CCSC). The channel is being deepened from a previously authorized depth of 47 ft to a new authorized depth of 54 ft below mean lower low water (MLLW). In order to develop a Dredge-Material Management Plan (DMMP), it is important to evaluate potential shoaling rate changes due to the channel improvements. Changes in channel configuration can influence shoaling in any of several ways. Some of these are: i) Increased deposition associated with the increased channel bed surface area ; ii) Increased deposition associated with decreased tidal velocity due to increased channel cross-sectional area; iii) changes in the location and quantity of fine sediment deposition due to changes in the flocculation of fine sediments associated with altered salinity intrusion characteristics, and iv) Other factors, which may include greater bank and bed erosion due to changes in vessel traffic (vessels generate waves that can erode banklines) , increased trap efficiency of channel junctions and turning basins, etc.
To investigate and quantify the potential for changes to sedimentation associated with channel deepeningthe Adaptive Hydraulics (AdH) numerical model code, coupled to the SEDLIB sediment transport librarywas used to develop a 2D (vertically-averaged) hydrodynamic, salinity, and (quasi-3d) sediment transport model of Corpus Christi Bay and the surrounding area (Aransas Bay, Nueces Bay, Baffin Bay) that extends from the Gulf of Mexico inland to the extent of significant tidal influence. This model was applied to both the existing and plan channel geometries, and modeling results were analyzed to determine the impact of the proposed conditions on dredging requirements in the Federal Channels. Both existing and plan channel conditions were evaluated for one simulated year, for both the existing sea level elevation at the ocean boundary, and one for future condition for which the cumulative elevation associated with 50 years of estimated future sea level rise was applied at the boundary. The model was also simulated with vessel effects, where typical vessel tracks are applied to the model, and the resulting bow wave and drawdown are propagated through the model domain. This was done to evaluate vessel effects on sediment transport and shoaling rates. The results of this model application will be used to identify locations where significant shoaling can be expected (with and without project conditions) and to determine the advanced maintenance requirements necessary to maintain the desired dredging cycle of approximately 3-4 years.
Presenter Bio: Gary L Brown is a Research Hydraulic Engineer in the Coastal and Hydraulics Laboratory at the U.S. Army Engineer Research and Development Center (ERDC) in Vicksburg, Mississippi. He is a contributing developer of the Adaptive Hydraulics (AdH) numerical model, and he is the primary developer of the SEDLIB sediment transport library. His past applied work has included modeling of hydrodynamics, salinity, and sediment transport in rivers and estuaries throughout the United States. Most recently, he conducted a multi-dimensional modeling effort investigating the effects of proposed sediment diversions with respect to inundation, salinity, and land-building in the Mississippi Delta.
Helping River Sand Move to the Coast: The Santa Ana River Sand Management Project
Kim Garvey, Moffatt & Nichol
Co Authors: Jim Volz
The Santa Ana River is a significant source of sand to southern California beaches. Before the river was dammed and channelized, it was estimated to have yielded up to 650,000 cubic yards per year to the coast. Today, only a fraction of this sediment naturally makes its way to the coast; human intervention is required to remove sand impounded within the river and move it to the downcoast beaches. Since the Santa Ana River is a flood control channel within a large urban area, periodic sediment removal is required to maintain the channel capabilities, which in turn provides the opportunity to move some of the impounded river sediment to the beaches.
Clearing of the lower Santa Ana River sediment has occurred periodically over the last several decades. The most recent event was in 2016-2017, led by the Orange County Flood Control District. Approximately 650,000 cubic yards of sand were removed from the river and beneficially used on regional beaches. (Ironically, this is the same amount of sand that was historically delivered to the coast on an annual basis).
Placing sand on beaches is rewarding but not without its challenges. For the most recent Santa Ana River project, some of the challenges included working in a flood channel during winter months (required timing due to sensitive bird nesting windows), working in the tidally-influenced mouth of the river, potential impacts of sand placement in popular surfing areas, need for eelgrass habitat mitigation, and Federal and State permits processing timelines.
The County contacted several local agencies early in the planning process to survey for their beach sand needs. Due to this early outreach, these cities were included in the regulatory permits which allowed for the Santa Ana River sand to be placed on their beaches opportunistically when/if funding was available.
This presentation will provide an overview of the recent Santa Ana River beneficial use of dredge material project and discuss the challenges and successes associated with the permitting, design, and construction.
Presenter Bio: Ms. Garvey is a Coastal Engineer at Moffatt & Nichol who has worked on and led a variety of coastal projects. These projects have included beach nourishment, dredging, wetlands restoration, shore protection, ports and marinas. Prior to joining Moffatt & Nichol, Ms. Garvey was an Engineering Director at Boeing.
Methods to Reduce Water Column Turbidity from Hydraulic Dredge Placement; A Literature Review
Brandon Hill, AECOM
Co Authors: Brandon Hill, Carl Sepulveda, Nathan Mezzano
Populations grow, more and larger ships circumnavigate the globe, human nature drives us to the coast seeking ever-diminishing pristine shorelines, and all the while the coastal practitioners continue to strategically manage the precious resources that they have control over. One such resource is the finite amount of sediment which must be removed and repurposed with precision and forethought. This delicate balance facilitates beneficial use of dredged material (BUDM), valuing dredged sediments and prioritizing the positive impact that it can have on a community.
As coastal practitioners address the multifaceted pressures that their communities face even the fine-grain details can have a large impact. This presentation will explore the benefit, issues, and constraints, of reusing hydraulically placed dredged material for ecological good amid sensitive environments and the need to control discharged BU sediments. For exampleusing the material in oyster reef restoration where an abundance of established sensitive oyster habitat creates restrictive placement area conditions. Other applications found in the literature will also be reviewed.
The technology and techniques to minimize the impact of discharged dredge material on nearby delicate, aquatic environment is a well-explored subject. This presentation will summarize the key findings of several literature sources and posit the best path forward. It will explore environmental dredging hydraulic placement methods such as downpipes, multi-tremies, and submerged diffusers as well as containment techniques like confined aquatic disposal cells or beneficial use-based oyster reefs.
Rather than dipping into a highly granular technical discussion, this presentation will provide an accessible discussion into how specific practices can be crucial to fulfilling the vision of a holistic regional sediment management approach.
Presenter Bio: Brandon HillI, MMRM is a Coastal and Environmental Planner II with AECOM. As a project manager, he assists in the planning and implementation of large-scale dredging, BUDM, and RSM Projects. He specializes in systems management approach based upon experience in Six Sigma, municipal government, and research. While earning his Masters in Marine Resource Management from Texas A&M Hill worked as a NASA-funded researcher. Serving as a municipal Shoreline Director he built 1.7 million dollars worth of beach access infrastructure, crafted the city comprehensive plan and shoreline master plan and enhanced erosion response through nourishment strategies built upon particle tracing studies.
Design and Lessons Learned – Phase I of the Post Florence Renourishment Project, Bogue Banks, N.C.
Greg Rudolph, Carteret County Shore Protection Office
Hurricane Florence (2018) was the storm of record based on many metrics (water level, sand loss, etc.) for the ~25 mile long island of Bogue Banks, N.C. Beach and inlet management for the area is guided by the Bogue Banks Beach Master Plan that provides various volume and spatial prompts to implement shore protection and inlet rehabilitation measures; and was the core document utilized to secure regulatory permits and authorization pathways for the next 50 years. In the wake of Florence, ~5.2 miles of beach encompassing the jurisdictions of Indian Beach, a portion of Salter Path, and Eastern Emerald Isle lost ~945,000 cubic yards (cy) of sand; including most of the incipient dune field that dominates the beach front, and in rare cases, part of the primary dune as well. Utilizing the Master Plan permitting vehicle, Carteret County and the municipalities via their engineering team at Moffatt & Nichol, swiftly developed plans & specifications and successfully solicited an awardable bid to replace the sand lost during Florence and to mimic the geometry of the pre-existing incipient dune system.
The beach nourishment project was awarded to Great Lakes Dredge & Dock for ~$20.5 million and started on March 8, 2019 with the Liberty Island dredging sand from the authorized borrow site of the ODMDS, a component of the Morehead City Harbor Federal Navigation Project located 2 to 3 miles offshore near Beaufort Inlet. The Liberty Island completed Reaches 3 (Indian Beach East/Salter Path) and 2 (Indian Beach West) delivering 158,263 cy of sand and 192,428 cy to these reaches, respectively (350,691 cy total). Reach 1 (Emerald Isle East) was initiated on March 29th and completed on April 25th entailing 624,945 cy – resulting in a total project volume of 975,636 cy. The Liberty Island was accompanied by the Ellis Island during the time period of April 8th to the 18th to help complete the project.
The beachfill in cross-section was contoured by; (1) tying into the existing, eroded frontal dune at +12 feet NAVD 88 and maintaining that top dune elevation at vary lengths progressing seaward, (2) the newly constructed dune face was graded on a 5:1 slope to the elevation of +6 feet NAVD 88, (3) the berm was extended from dune toe/berm interface seaward at +6 feet NAVD 88 at varying lengths, and (4) the slope of the fill from the berm crest out to sea was on a 20:1 slope. The newly created dune crest and slope was vegetated with Sea Oats and Bitter Panicum (lesser extent) as part of the contract. The dune toe/berm interface could be considered as the anchor point of the project’s design as this represented the spatial position of the vegetation line pre-Florence.
Positive lessons learned from the overall project design, on-the-fly surveying and template adjustments, and endangered species trawling-relocation protocols will ideally be implemented for Phase II of the Post-Florence Renourishment Project – tentatively scheduled for winter 2019-2020, encompassing Central and Western Emerald Isle, Pine Knoll Shores, and East Atlantic Beach.
Presenter Bio: Greg “rudi” Rudolph is Carteret County’s Shore Protection Manager, where he coordinates and develops the County’s beach and inlet preservation program, and serves as a policy analyst for County governments as it pertains to sea-level rise, endangered species, waterway dredging and a host of other coastal issues. He is responsible for an annual budget of approximately $3.5 million and serves as secretary to the County’s Beach Commission, which is an 11 member County Commissioner appointed body created in 2001. Rudi holds three degrees including a M.S. in Coastal Geology and B.S. in Geology from East Carolina University, and a B.A. in Biology from UNC-Charlotte.
Environmental coordination among Federal, state, local, and private entities for Bogue Banks beach nourishment
Deena Hansen, Bureau of Ocean Energy Management
Co Authors: Leighann Brandt, Douglas Piatkowski
To meet all environmental requirements and consultations for the Bogue Banks Master Beach Nourishment Plan (“The Plan”), multiple entities coordinated on documents, negotiations, implementation, and reporting. To nourish coastal beaches according to The Plan and in response to Hurricane Florence, Carteret County identified several sources of sand. Among these was the Current Ocean Dredged Material Disposal Site (ODMDS) located in federal waters under the Bureau of Ocean Energy Management (BOEM)’s jurisdiction. For the 2019 nourishment event, then, BOEM granted the County access to federal sand resources through a negotiated agreement. Before leasing the sand, BOEM partnered with the U.S. Army Corps of Engineers (USACE) to analyze impacts and meet environmental requirements, as outlined in the National Environmental Policy Act (NEPA), Endangered Species Act (ESA), and Coastal Zone Management Act (CZMA), among others. Dial Cordy, a third-party contractor, supported many of these federal consultations, in particular with the development of an Environmental Impact Statement (EIS) and Biological Assessment (BA). While consultations were underway, USACE and BOEM worked with other federal partners like the National Marine Fisheries Service and U.S. Fish and Wildlife Service, while maintaining communication with the County and contractors. Through these consultations, environmental requirements and recommendations became part of the project.
Once construction began, BOEM coordinated with state and federal partners to ensure the County and dredging contractor, Great Lakes Dredge and Dock (GLDD), understood the environmental stipulations and reporting requirements. As the project encountered new issues and challenges, all partners worked quickly to address the circumstances and keep the project on track, while maintaining environmental stewardship responsibilities. This coordination required clear communication and led to decreased redundancy, streamlined compliance, and overall better outcomes, for both the project and the environmental resources.
Presenter Bio: Deena Hansen leads environmental compliance for dredging projects in federal waters that are under the jurisdiction of the Bureau of Ocean Energy Management (BOEM).
Engineering Design of 50-Year Bogue Banks Master Beach Nourishment Plan and Post-Florence Phase I Project
Nicole VanderBeke, Moffatt & Nichol
Co Authors: Katie Finegan, Johnny Martin
Carteret County, the Carteret County Beach Commission, and the Shore Protection Office (SPO) seek to provide long-term, sustaining management of Bogue Banks beaches. In 2001, by state legislation, the Carteret County Beach Commission was established, and a room occupancy tax (ROT) for funding beach nourishment and related functions was put in place mainly as a response to the hurricanes of the 1990’s (Bertha, Fran and Floyd) and subsequent storms. Carteret County intends to maintain Bogue Banks beaches via implementation of this proposed Master Beach Nourishment Plan (MBNP) with guidance from the SPO and oversight by the Beach Commission.
The proposed program incorporates actions within multiple oceanfront municipalities to nourish recipient beaches, via use of multiple sand sources, over a multi-decadal timeline with revolving nourishment-project events. The overall plan identifies MBNP engineering design elements including: sand volumes required to yield the desired level of protection throughout Bogue Banks; triggers expected to prompt future nourishment events; sand borrow sources, volumes, quality, and viability; the expected capacity of the recipient beaches for nourishment; and the projected timing of nourishment events. The plan also integrates inlet management for protection of adjacent infrastructure by use of a demarcated “safe box” or corridor for the inlet to migrate within. Once the inlet reaches the edge of the box, an inlet relocation project would be initiated to return the inlet to a more stable location. Lastly, the plan also investigates the use of cost-effective analytical (statistical) design procedures versus complex modeling to determine the differences in results and recommendations from each approach.
The first project implemented under the MBNP was the recently completed Post-Florence Renourishment Project – Phase 1. The project included ~5.2 miles of beach encompassing the jurisdictions of Indian Beach, a portion of Salter Path, and Eastern Emerald Isle with an approximate volume of ~945,000 cubic yards (cy) of sand; including replacement of most of the incipient dune field that dominates the beach front, and in rare cases, part of the primary dune as well. This presentation will explore the engineering design aspects of the MBNP as well as the Post-Florence Phase 1 project.
Presenter Bio: Having joined Moffatt & Nichol in 2005, Ms. VanderBeke has 14 years of providing engineering support and management for coastal engineering projects. She has been involved in multiple annual shoreline and beach volume change analysis programs, development of shoreline stabilization and beach nourishment projects, analysis of borrow area and native beach sediment data, wave environment analysis, coastal flooding studies, coastal floodplain mapping, and 1D numerical shoreline modeling.
Dredging Challenges Now and Future
Samuel Morrison, Moffatt & Nichol
Bogue Bank Master Plan – Dredging Challenges Now and in the Future.
In the development of the Bogue Banks master plan, which was implemented to provide a level of protection that was at a minimum able to withstand a 25-year storm event. This level of protection initiates the need for beach re-nourishment based on certain triggers that identify minimum beach fill quantities needed to be maintained in order to satisfy the protection levels. As part of the development of the 50-year plan it needed to be determine the approximate quantity of beach fill material that would be needed over the life of the Master Plan. When identifying the sources of the beach fill sand, availability and cost are major factors. As Hurricane Florence (2018) showed us we also can’t always predict when the re-nourishment cycles are going to occur and the availability of contractors. One of the greatest challenges from re-nourishment perspective is when an emergency re-nourishment is caused by storm event is to make sure the sand source is available and hope there are contractors available. For the Bogue Banks project the dredging window is November 15th thru April 30th, the typical turtle window for utilizing hopper dredges in the South Atlantic and the Gulf. With the limited number of companies utilizing hopper dredges and many of them booking up early for the typical turtle window season it is often dificult to obtain competitive bids as their may be limited contractor availability or simple market forces dictate much higher prices when the project is not schedule and bid well in advance of the anticipated work , difficult to accomplish when it is emergency work.
As there are varying sizes of dredges in the market, and not controlling what dredge will be bidding/employed on the project as the design engineer we need to plan to design/bid the most effective beach fill densities for the larger dredges as they have a difficult time controlling the fill into “thin” sections which we all now there is really no such thing as free sand. We also need to take into consideration the project size for the allotted time within the turtle window, which limits the size of the project if we want to make sure to allow the smaller dredge to be able to accomplish. Benthic resources in the borrow area and sea turtle / turtle trawling are also considerations as turtle takes can abruptly shut down the project prior to completion which is not good for the contractor or the project.
Although Atlantic Beach gets material for the inlet dredging every 3 years from the inlet maintenance dredging we need to have a back-up plan for emergency re-nourishment in this area as well.
Finally, I wanted to talk about the actual work done by GLDD on the first project, Dredge Liberty and Ellis Island, there performance on the project and some of the things that went well and did not go so well.
Presenter Bio: Have recently been serving as a Technical Director of Dredge Services with Moffatt & Nichol over the past year. Prior to that, I served for over 29 years with Great Lakes Dredge and Dock Company in a variety of roles from Field Engineer to Vice President – Division Manager of Middle East Operations. He received a Bachelor of Science degree in Construction Engineering Technology from Purdue University.
Novel Numerical Modeling of Storm Surge using a Reduced Dimension DSW Approach
David Kelly, Florida International University
State-of-the-art storm surge forecast models typically solve the non-linear shallow water (NLSW) equations on unstructured computational grids. More often than not, these models run on static computational grids that are defined before the simulation begins. There are some notable exceptions such as a model based on the GEOCLAW package  and the Fully Adaptive Storm Tide (FAST) model which both apply dynamic adaptive mesh refinement (DAMR) to evolve the computational mesh as the solution progresses in time . The main limitation of the present storm surge models are the inflexibility of the grid which is fixed in time (meaning that the optimal structure of the mesh has to be known by the user a priori), stability restrictions of explicit numerical schemes (which are constrained by the CFL condition ) and the use of shared-memory , as opposed to distributed memory, type parallelization. Moreover, depth-averaged storm surge models, are based almost exclusively on the NLSW equations. The hyperbolic NLSW equations form a highly simplified subset of reduced dimension shallow water models. These equations are obtained by depth-averaging the Euler equations with the assumption of hydrostatic pressure. Improved reduced dimensional descriptions are obtained by including the non-hydrostatic pressure contribution. These descriptions differ from the usual NLSW equations by the presence of higher-order dispersive terms whose origin lies in the vertical acceleration, and so are termed dispersive shallow water (DSW) theories. In this work a DSW storm surge model has been established within the framework of a DAMR numerical model. The model includes a novel numerical scheme for the advective terms that is based on a discrete velocity lattice gas model with suitable macroscopic properties. The dispersive terms are handled via a conventional high-order finite difference approach. A number of numerical experiments to hindcast the surge due to two recent historical hurricanes in the State of Florida, namely hurricane Irma (2017) and hurricane Michael (2018,) have been conducted. The inclusion of dispersion allows for wave-by-wave of dynamic overtopping within a sub-domain of the nearshore region. This is achieved using the spectral wave model SWAN  to provide a wave spectra in-order to drive the DSW model in order to simulate the surf-zone processes and dynamic run-up. It should be noted that simulation of dynamic run-up is a significant improvement on the current state-of-the-art which is a static set-up computed through the combined use of the NLSW surge model and a spectral wave model. Comparisons between static and dynamic run-up models in terms of the maximum envelope of water (MEOW) and the predicted maximum high water marks will be presented. Examples of selected numerical experiments will be presented and the associated results will be analyzed and discussed at conference.
References Kelly, D.M., Teng, YC., Li, Y. (2016) Validation of the FAST forecast model for the storm surges due to hurricanes Wilma and Ike Nat Hazards 83: 53-74.  Mandli KT, Dawson CM (2014) Adaptive mesh refinement for storm surge. Ocean Modell. 75:36-50.  Courant, R., Friedrichs, K., Lewy, H. (1967) On the partial difference equations of mathematical physics IBM Journal of Research and Development,11 (2): 215-234  Booij, N., Ris, R. C. and Holthuijsen, L. H. (1999), A third-generation wave model for coastal regions, Part I: Model description and validation, J. Geophys. Res. 104(C4) 7649-7666
Presenter Bio: Dr. David M. Kelly completed his undergraduate Degree In Environmental Physics with first-class honors from the University of East Anglia, Norwich, UK in 2000. Following on from this, after a short spell teaching English in Italy, Dr. Kelly completed a Post Graduate Certificate of Secondary Education (PGCE) in Physics at the University of Bristol (UK) in 2002. After working for four-years teaching Advanced Level Physics to 16-18 year olds Dr. Kelly undertook a PhD in Environmental Fluid Mechanics in the School of Civil Engineering at the University of Nottingham, UK. The PhD, which involved developing a novel new numerical model for swash zone hydro- morphodynamics, was undertaken under the supervision of Professor Nicholas Dodd (himself a student of the late, great, Professor D. H. Peregrine). Upon completion of his PhD, in January 2009, Dr. Kelly won a post doctoral position on the prestigious UK government Knowledge Transfer Partnership (KTP) program in which the UK government funds the transfer of excellent research to leading industrial partners. This two-year collaboration was between the University of Nottingham and HR Wallingford, UK. After completion of the KTP Dr. Kelly was employed by HR Wallingford as a Senior Research Engineer. During this time Dr. Kelly developed a new numerical model to simulate Tsunami hydro- morphodynamics and added a compressible air phase and sediment transport to HR Wallingford’s, openFOAM based, CFD model as well as making significant contributions to the Électricité de France (EDF) Telemac model. Whilst at HR Wallingford Dr. Kelly co-supervised two PhD students who continued developing models initiated by Dr. Kelly. Following on from this Dr. Kelly worked at the International Hurricane Research Center (IHRC), at FIU on the development of next generation storm surge models. Dr. Kelly is then worked as a Senior Engineering Scientist at W.F Baird & Associates, Canada before returning to FIU as an Assistant Professor in MME.
An Overview of ERDC’s Coastal Storm Modeling System as Applied to the South Atlantic Coast Study
Margaret Owensby, USACE-ERDC-CHL
Co Authors: Mary Bryant, Chris Massey, Ty Hesser
The U.S. Army Corps of Engineers Engineer Research and Development Center’s Coastal Storm Modeling System (CSTORM-MS) is a comprehensive methodology for applying a system of highly-skilled, highly-resolved numerical models to simulate coastal storms in order to accurately assess flood risk to coastal communities. The CSTORM-MS makes use of nonlinear physics-based models that are integrated into a suite of high-fidelity storm modeling tools to support a wide range of coastal engineering needs for simulating tropical and extratropical storm wind, wave and water levels and for representing the coastal response due to the storms. The CSTORM-MS has been applied to several large-scale USACE projects including the North Atlantic Coast Comprehensive Study (2015), the Coastal Texas Protection and Restoration Study (2018) and now the South Atlantic Coast Study. This presentation describes the current state of practice capabilities of the CSTORM-MS and its accompanying production system (CSTORM-PS) for efficiently executing modeling scenarios and storing data. Included will be an overview of the modeling system, as applied during the South Atlantic Coast Study. Additionally, a brief discussion on how the modeling results and computed statistical annual exceedance probabilities are stored in the Coastal Hazards System for access and use for many purposes in the engineering and planning communities.
Presenter Bio: Ms. Margaret Owensby is a research hydraulic engineer with the U.S. Army Corps of Engineers at the Engineer Research and Development Center in Vicksburg, Mississippi. Since joining the Corps of Engineers in 2016, she has specialized in coastal modeling and data analysis, and has worked on a variety of projects to aid decision-making for both government and military agencies. She is a member of the Coastal and Hydraulics Laboratory’s Coastal Storm (CSTORM) Modeling System team, which uses a coupled numerical model to simulate both historical and hypothetical hurricane conditions in coastal regions.
Surface Response Method with Optimal Storm Sampling for Surge Prediction.
William Chilton, University of North Florida
On the Gulf of Mexico and Atlantic seaboards in the eastern United States, the past 30 years have given rise to storms that have resulted in tremendous economic damage. Storm surge is considered the most damaging factor of a hurricane. In this time coastal development has continued to expand, and populations still rise. While the process of communicating an evacuation order has improved, the process of quantifying the risk posed to infrastructure and development along the coast still presents a challenge. The goal is to find a reliable way to quantify future risks and reduce human and economic losses moving forward. When examining storms, we have history, and statistics. The typical variables of interest are forward velocity, incident angle to shore normal, radius of maximum winds, intensity, and location of landfall. Two prominent JPM branches are Bayesian Quadrature (BQ) and Surface Response Method (SRM). BQ offers finite points within a parameter space where direct interpolation or extrapolation is instead replaced with influence patterns. These patterns will guide the sampling pattern. However, there is a restriction to the points in the parametric space. There has been no reliable way to know what happens between the points in space. SRM allows for probability density to be defined for any point in parametric space. To date methods using SRM have been developed for uniform spacing. This limits the ability of such a powerful method to increase resolution at more sensitive coastal configurations. How is the parametric space organized or optimized? If conducting simulations with multiple tracks for each storm type, what is sufficient spacing? What are the limitations presented by the configuration of the coast? Is there a way to reach a measure of uncertainty that remains in the approximation? If so how can we reach this, and what is the test that must be applied to maintain reliability of the method? Results will show that parametric space can be interpolated with an optimal set of storms using the SRM, and that is can be applied to many different coastal configurations.
Presenter Bio: W. Paul Chilton is a graduate student at the University of North Florida. His interests lie in coastal resiliency, risk assessment, and coastal processes.
Restoration of Shallow Water Habitat in Hudson River Estuary – Rattlesnake Island Hydrodynamic and Sediment Transport Study
Ahintha Kandamby, OBG Part of Ramboll
Co Authors: Anthony Eallonardo, Shaun Gannon, Daniel Miller
Channelization and the construction of dikes in the early 20th century along the Hudson River Estuary resulted in the loss and degradation of shallow water habitats, and these effects are implicated in the decline of American shad (Alosa sapidissima) and the dominance of invasive species (e.g., water chestnut, Trapa natans) in backwaters with altered flow regimes. Such conditions exist at Rattlesnake Island and Coxsackie Cove where a wing dike partially blocks the side channel flowing into the northern end of Coxsackie Cove and has created a contiguous backwater with degraded environmental conditions and relatively low fish densities. This site provides an outstanding opportunity to evaluate the restoration of shallow water habitats because the potential degrading factor (the dike) is clear and modifiable, and the potential restoration gains are substantial. These gains include the creation of extensive habitat for numerous fish species including American shad and river herring (Alosa pseudohargengus and A. aestivalis) and the reduction of extensive water chestnut beds.
To better understand the impacts of dike modifications on the habitat, physical conditions, and flow regimes of Coxsackie Cove and associated areas, 2-D hydrodynamic and 2-D sediment flux models were developed. These models predict Hudson River hydrologic fluxes and sediment transport potential under the tidal conditions, and they provide an opportunity to develop a “proof-of-principle” test for a given restoration design before implementing such modifications to the Hudson River.
Three scenarios were modeled: Baseline (no change from current dike condition), 100% Removal (complete removal of the dike), and 100% Removal and Supplemental Channel (complete removal of the dike and construction of a shallow channel in the northern portion of Coxsackie Cove). Each proposed scenario was evaluated for long term (30-Day) tidally influenced and 1-Yr. storm sediment transport behavior in the cove area. Compared to the current condition, the removal of the dike with or without installation of a supplemental channel is predicted to, 1) increase the areal extent of maximum flow velocity within Coxsackie Cove, 2) reduce the bed shear stress between the northern end of Rattlesnake Island and the mainland, 3) reduce erosion/deposition in the northern portion of the cove and increase it in the southern portion of the cove, and 4) slightly increase the water depth within the cove. Collectively, these effects from dike removal would likely lead to improved habitat conditions in Coxsackie Cove. Additionally, a 3-D hydrodynamic and sediment transport simulation was performed to validate the 2-D erosion and deposition patterns and depth with suspended sediment transport concentrations along cross sections and longitudinal sections within the cove.
Presenter Bio: Dr. Kandamby is an experienced hydrology and hydraulics numerical modeler in the water resources consultancy industry. He has a Ph.D., in numerical modeling of river ice hydrodynamics and a MSc in numerical modeling of deep water oil spills from Clarkson University in Potsdam NY. He is a professional engineer in state of NY and a certified floodplain manager in state of PA, and working with OBG Part of Ramboll, assisting on numerous Computational Fluid Dynamics (CFD) and 1D / 2D hydraulics and sediment transport modelling.
Emerging Techniques to Address Compound Flooding: What We Know, What we Don’t, and What We Need Moving Forward
Raymond Caldwell, U.S. Army Corps of Engineers – Galveston District
As the largest civil works project in the history of U.S. Army Corps of Engineers Galveston District (USACE SWG), the $3.9B Sabine-to-Galveston (S2G) project is currently in the Pre-construction, Engineering and Design (PED) phase. Even though the primary focus of this Coastal Storm Risk Mitigation (CSRM) project is mitigation of risk from coastal storm surge and wave hazards, rainfall-induced interior flooding and interactions of rainfall-induced flows with coastal surge are important drivers towards informing a holistic risk-based design and accounting for the various sources of flooding risk to the CSRM system.
Recent tropical cyclone events (e.g. Harvey, Florence) have demonstrated that constructive interactions between rainfall-induced riverine flows and coastal surge can play a critical role in an evaluation of combined flood risk and design as well as operation of flood risk management systems. Broadly, a compound flooding event corresponds to flooding with multiple drivers (e.g., surge, riverine flow, rainfall) interacting with each other and contributing to the overall flood risk/impact. The impacts from compound flooding can range from influencing the design elevations of perimeter flood protection levees and floodwalls, to operational optimization of existing pumping systems to mitigate interior drainage flooding. On 2-3 April, 2019, USACE SWG hosted a two-day workshop entitled “Compound Flooding due to Interactions between Coastal Storm Surge and Rainfall-induced Riverine Flows” with leaders from USACE, USGS, NOAA, FEMA, and academic experts from across the nation, to discuss currently available, and emerging technologies in statistical and dynamic modeling, available to support S2G and other USACE projects affected by compound flooding events. In addition, the workshop addressed similar challenges being faced by communities elsewhere around the country, and the immediate needs of engineers and public officials in assessing, evaluating and communicating this potential risk.
This paper will present a summary of the discussions during the workshop including lessons learned from past practice, gaps in current practice, needs for development of more robust tools/models, and focus areas for research efforts aimed at a comprehensive understanding of compound flood risk. The challenges and opportunities associated with utilizing observational in-situ data, synthetic data from numerical modeling, numerical model coupling methodologies (loose one-way to tight and full two-way coupling), parameterization and modeling of precipitation associated with tropical cyclones (parametric rainfall models such as PHRaM and others), univariate and multi-variate statistical models (copulas and surrogates), addressing climate change impacts including sea level rise, and others aspects of compound flooding will be discussed. A companion paper at this conference by Malagon-Santos et al. (“Using Multivariate Statistical Modelling to Assess Compound Flooding Effects in Sabine Lake, Texas”) will present a detailed case study at Sabine Lake, TX illustrating the application of available data, methodologies and tools.
Presenter Bio: Dr. Caldwell is Water Control Manager for the US Army Corps of Engineers in Galveston, TX. He has over 20+ years of experience in hydrometeorology, specifically in numerical modeling of atmospheric and hydrologic processes related to flood risk management systems in federal, state, and local governments, as well, as private sector industry. With a focus of research-to-applications, Dr. Caldwell seeks to identify key needs in the wider community through collaborative efforts and bring academic discovery to real-world action. He is a Professional Surface Water Hydrologist, Professional Engineer, and Certified Consulting Meteorologist.
Using Multivariate Statistical Modelling to Assess Compound Flooding Effects in Sabine Lake, Texas
Victor Malagon Santos, University of Central Florida
Co Authors: Thomas Wahl, Shubhra K. Misra, Kathleen D. White
Compound flooding is caused by the interaction of two (or more) contributing hydrological/hydraulic forcing variables, which may or may not be considered extreme themselves, leading to extreme impacts. Both extra-tropical and tropical storms can result in compound flooding events with a wide range of consequences for coastal assets and people living near the coast. Storms featuring very low pressure and strong winds can drive storm surges whose flooding impacts can be aggravated by heavy rainfall-induced flow. For instance, hurricane Isaac in 2002, and most recently Hurricanes Harvey, Irma, and Florence in 2017/2018, all led to significant damages and loss of lives due to the interaction between storm surge and precipitation/discharge processes. Despite these important impacts for coastal flood risk management, only recently have compounding effects caught the attention of communities, engineers and risk management officials. One of the reasons why compound flooding has been ignored in the past within the design/engineering and risk management practices has been the lack of reliable methodologies to assess the related processes with coupled process-based and statistical models. A proper understanding of compounding effects is necessary to avoid flood risk miscalculations when building/upgrading flood defenses to mitigate risks associated with high-impact events.
Here, we assess compound flooding effects in Sabine Lake, TX, as part of the Sabine to Galveston Pre-construction, Engineering and Design project, which aims to build/update coastal storm risk management systems in the area. Sabine Lake receives discharge from two rivers and is connected to the Gulf of Mexico through Sabine Pass. These geographic characteristics make it potentially susceptible to compounding effects, which are being thoroughly explored. First, we perform a dependence analysis between surge and the combined discharge from both rivers using overlapping records from water level and river gages in the wider area. Second, univariate and multivariate models are used to assess how compounding effects modulate multivariate return periods/annual exceedance probabilities (AEP) of flood levels in the area. During the last few years, copula-based multivariate extreme value models have played an important role in assessing compound flooding processes as they are capable of capturing and modelling the dependence structure of the contributing variables. We test the adequacy of different copula models to derive joint distributions that optimally represent existing dependencies and allow us to reliably estimate joint return periods for different discharge and surge scenarios. Then, compounding effects are evaluated by comparing annual exceedance probabilities obtained through copula models and those derived under the independence assumption (i.e. no dependence exists between contributing variables).
Preliminary results suggest that dependency between discharge and surge in the Sabine Lake area is statistically significant, although small in magnitude, leading to a total water level difference of up to 10 cm between dependence and independence cases for an event with a combined AEP of 2%. Short data records and the presence of data gaps complicate the analysis and we explore various approaches to include additional in-situ data from nearby stations as well as synthetic data from numerical models.
Presenter Bio: Victor Malagon Santos is pursuing a PhD in Civil engineering at the University of Central Florida, where he is focusing on combining numerical and statistical models for coastal hazards analysis. He undertook a double bachelor’s degree in Oceanography and Environmental Science at the University of Cadiz (Spain), and attained his Master’s degree in Engineering in the Coastal Environment after graduating from the University of Southampton (UK). His main research interests include, but are not limited to, coastal oceanography and morphodynamics, flood risk assessments, numerical and statistical modelling of coastal processes, and changes in waves, tides and sea level.
Compound Flood Modeling of the Upper Coast of Texas
Amine Kiaghadi, Oden Institute for Computational Engineering and Sciences at UT Austin & CIVE Department at the University of Houston
Co Authors: Babak Poursartip, Mark Loveland
In this study, we describe coupled storm surge and rainfall-runoff models targeted towards evaluating flood mitigation projects proposed by the U.S. Army Corps of Engineers for the Beaumont-Port Arthur, Texas region. This region is vulnerable to both surge and riverine flooding from the Nueces and Sabine watersheds. The modeling framework includes the Advanced Circulation (ADCIRC) model for storm surge, combined with HEC-RAS models of the various watersheds. Of particular interest in this study is how and where to couple the models to capture both the impact of surge on river stage, and the riverine inflow into the bays and estuaries and its interaction with the surge. This research could influence similar coupling strategies in other regions of the U.S. Test cases from recent hurricanes, including Ike, Rita and Harvey will be presented.
Presenter Bio: Amin Kiaghadi earned his Ph.D. in Environmental Engineering from the University of Houston. He is a joint appointed postdoctoral fellow working under the direction of Dr. Clint Dawson at Oden Institute for Computational Engineering and Sciences at the University of Texas at Austin, and Dr. Hanadi Rifai at the University of Houston. Dr. Kiaghadi’s research interests include hurricane storm surge modeling, rainfall-induced flooding, fate and transport of spills during severe hydrologic events, water and sediment quality, geospatial models, machine learning, and water-energy nexus.
A New Lagrangian Shallow Water Approach for Storm Surge Modelling
Abhijeet Chodankar, Florida International University
Co Authors: David Kelly
Climate change can lead to extreme and frequent storm surge events, and hence there is an urgency to improve storm surge forecast models to predict coastal inundation and avoid loss of human life. Wind shear, tides, low pressure system, bed shear stress, coastal configuration, and bathymetry strongly influence storm surge events. The present operational numerical storm surge models are classified into 2D models (WAQUA-in-Simona, BSHsmod(Germany), MI-POM, IIT-D, SLOSH, JMA-MRI) and 3D models (NPAC(Canada), HIROMB) models. Storm surge models developed presently are based on non-linear shallow water equations (NLSW) employing finite element technique (IIT-D), baroclinic technique (HIROMB), barotropic technique (Nivmar), finite difference technique (CS3 tide surge(UK), SLOSH), and hydrodynamic technique (Mike 21(Denmark), Caspian Storm Surge (Kazakhstan)). State of the art research codes use curvilinear (CEST model) or unstructured grids (ADCIRC, UnTRIM , FVCOM , and SELFE models). Curvilinear grids are more flexible than Cartesian meshes, while unstructured grids can provide coarse resolution at ocean basins and fine resolution at the coast, thus avoiding the use of high resolution throughout the computational domain. The main limitations of the present storm surge models are the inflexibility of the grid which is fixed in time, stability restrictions of explicit numerical schemes and the use of shared-memory, as opposed to distributed memory, type parallelization..
In order to alleviate some of the problems mentioned above, the model presented is based on the Lagrangian, rather than the Eulerian, form of the NLSW equations taking into consideration wind shear, tides, and bed shear stress. The Lagrangian form of the governing equations offers symmetric eigenvalues and characteristic directions, hence there is no necessity to use upwind difference scheme. In the Eulerian system, excessive numerical diffusion or noise in the numerical solution arises due to the treatment of the non-linear advection terms . This can lead to shocks being smeared badly . In the Lagrangian system, there is no explicit advection term, and numerical diffusion is minimized. The disappearance of the advection terms from the momentum equation favours symmetric centered differencing . In the presented model, the bathymetry is based on an Eulerian grid and the bathymetry data is collected using a Lagrangian based dynamic dual mesh system. The novelty of this research is that a dynamic adaptive grid simultaneously handles the non-linear advection term while
ensuring the optimal grid configuration for the current flow state. A dynamic adaptive mesh is a time dependent mesh, which allows mesh refinement in specific areas of the flow to resolve certain bathymetric and hydrodynamic features. It provides high resolution, higher accuracy, and also solves the steep gradient problem, and further lowers computational cost. It also implicitly solves the wetting and drying fronts. Further, the model will be made massively parallel using the message passing interface library (openMPI) to achieve distributed-memory-type parallelization. To conclude, a novel Lagrangian shallow water model, employing a dynamic adaptive Lagrangian grid, will be presented in order to optimize storm surge simulations whilst at the same time including physics based parameters, with the hope of predicting surge and inundation more accurately.
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Presenter Bio: Abhijeet Chodankar is presently pursuing his PhD degree in Mechanical Engineering at Florida International University. He completed his Masters degree in Petroleum Engineering at the University of Louisiana at Lafayette. He received a Bachelor in Mechanical Engineering from Goa University, India in 2013. His research interest lies in coastal modelling, marine hydrodynamics, and fluid-structure interaction.
Long Term Water Quality Monitoring Trends within New Hanover County North Carolina’s Tidal Creeks
Brad Rosov, APTIM
Co Authors: Brad Rosov
While New Hanover County is the second smallest county in North Carolina, it is also the second most densely populated. The county is bordered to the west by the Cape Fear River and to the east by the Atlantic Ocean. It can be characterized as and urban coastal county containing numerous tidal watersheds. The tidal creeks within the county provide a wide range of recreational activities for its ~230,000 citizens and visiting tourists each year. These creeks are generally rich in terms of aquatic, terrestrial and avian wildlife and support complex food webs (Odum et al, 1984; Kwak and Zedle, 1997). As such, protection of the water quality within these creeks is a high priority for New Hanover County. As growth and development continue within the City of Wilmington and the county, water quality has been increasingly threatened due to many factors including aging infrastructure, increased impervious surface area and subsequent stormwater runoff flowing into the creeks.
Realizing the value that these creeks bring to the county, APTIM has been contracted to monitor the water quality within seven of the county’s tidal creeks on a monthly basis since November 2007. Each month, APTIM collects data pertaining to dissolved oxygen, pH, salinity, turbidity, conductivity, temperature, Chlorophyll-A, enterococcus bacteria from 19 monitoring sites within these seven creeks. Over the past 12 years, long-term water quality trends have emerged providing local leaders the information required to make informed management decisions in an attempt to improve water quality, protect human health, and maintain the ecosystem services derived from these natural systems.
Several monitoring sites within one of the tidal creeks included in this long-term study have demonstrated chronically high levels of enterococcus bacteria since the study’s beginning in 2007. Over the years, several source tracking studies were conducted in partnership with UNC-Chapel Hill to determine the origin of this contamination. Results have shown that human waste is a contributing factor, however, at this time; the geographic origin of this contamination remains unknown. Several approaches are being evaluated to determine the source of this bacterial loading and will be discussed in this presentation.
Presenter Bio: Brad Rosov has over 17 years of environmental permitting, documentation, and biological surveying/monitoring experience; 12 years of which has been with APTIM where he serves as a Senior Marine Biologist and Client Program Manager. He utilizes his comprehensive understanding of the NEPA process to draft NEPA-compliant documents including EISs, EAs, BAs, and EFHs in support of various coastal projects. Mr. Rosov also leads permitting efforts at the state and federal level and guides clients through consultation efforts with various agencies. His fieldwork experience includes water quality assessments, salt marsh surveys, benthic invertebrate monitoring, hard bottom surveys, shellfish monitoring, and SAV surveys.
Locals Lead Indian River Lagoon Restoration
Matt Shelton, Tetra Tech, Inc.
Co Authors: Virginia Barker, Marcy Frick
The Indian River Lagoon (IRL) in Florida is an Estuary of National Significance, supporting one of the greatest diversity of plants and animals in the nation. However, the IRL has been degraded because urban stormwater runoff has increased pollutant loading, causing turbid conditions and algal blooms which negatively affect the aquatic community. These pollutants also contribute to muck accumulation, which releases nutrients, depletes oxygen, and creates a lagoon bottom that is not hospitable to marine life. The municipalities located in the IRL basin, led by Brevard County, decided to work together to restore and protect the IRL system.
Brevard County, working with Tetra Tech, developed and adopted the Save Our Indian River Lagoon Project Plan – a multi-pronged approach to Reduce, Remove, Restore, and Respond: reduce pollutant and nutrient inputs to the lagoon though cost-effective projects, remove the accumulation of muck, restore oysters and living shoreline ecosystem services, and measure progress to respond to changing conditions and new information. To implement the plan, the City Councils and County Commission approved a referendum for a ½-cent sales tax, which was included on the November 8, 2016 ballot. The sales tax passed by 62.4% of the votes and provides a dedicated funding source for IRL restoration projects throughout Brevard County over 10 years. To ensure the sales tax funding is used responsibly, the plan is adaptively managed through annual updates with input from an appointed Citizen Oversight Committee.
Since the plan was adopted in August 2016, it has been revised to reflect new projects and the latest information through updates completed in 2017 and 2018. In 2019, the plan is entering the third year of implementation and projects in all categories are proceeding. To date, 19 projects have been completed, 12 are underway, and 26 are under contract.
Presenter Bio: Matt Shelton is a Project Manager in Tetra Tech’s Water Resources Group in Cocoa, Florida. He has over 20 years of professional experience in technical support and project management for watershed management and restoration, environmental compliance and auditing, stormwater permitting and compliance, health and safety, and contaminated site assessment and remediation projects. Mr. Shelton has a B.S. degree in Environmental Health with minors in Biology and Geography from Salisbury University.
CZF Abstract: Monitoring Ecological Conditions of Estuarine and Near-Coastal Waters of the Mississippi Gulf Region
James Stribling, Tetra Tech, Inc.
Co Authors: Emily Cotton, Valerie Alley, Alice Dossett
The Mississippi Department of Environmental Quality (MDEQ) began monitoring its coastal waters in the early 1990s. From the inland estuaries, through Mississippi Sound, to approximately three nautical miles beyond the barrier islands, ecological monitoring began as part of the USEPA Environmental Monitoring and Assessment Program (EMAP-Estuaries) and continues through the cyclical USEPA National Coastal Condition Assessment (NCCA) and the annual Mississippi Coastal Assessment (MCA). The initial calibration of a State-specific biological indicator using benthic macroinvertebrates in 2013 resulted in the Gulf Benthic Index for Mississippi (GBI-MS). The GBI-MS multimetric index consists of several individual metrics that were tested for their capacity to detect gradients of natural and stressor conditions. The natural site classes were identified by comparing taxonomic composition among samples with relatively minimal disturbance (low sediment contamination by metals and organic compounds, high rates of survival in toxicity tests, and high dissolved oxygen). Taxonomic composition was evidently associated with gradients of salinity and silt/clay substrates. The most prominent benthic taxa showing in non-metric multidimensional scaling ordinations included Ophiurida (brittle stars) and Lumbrineris (Polychaeta), associated with high salinity; Parandalia and Streblospio (both Polychaeta), with low salinity; and Mulinia (Polychaeta) and Sigambra (Bivalvia), with low and high silt/clay, respectively. Effects of silt/clay percentage on composition were stronger in high salinity samples (>18ppt) than in lower salinity samples. Sensitivity of metrics was tested between sites within four site classes based on high salinity, low salinity, high silt/clay (>35%), and low silt/clay content. Samples from sites with relatively minimal human-induced disturbance were identified as a reference to which conditions in other sites were compared. Sites having evidence of stressors were identified as highly disturbed. The indexes (by site class) correctly identified poor biological conditions in 72–100% of highly disturbed sites and included between 3 and 5 metrics describing the richness, composition, feeding groups, and pollution tolerance of taxa in the samples. Following the initial calibration exercise, we undertook an effort to develop a monitoring network design that would allow not only assessment of individual sampling locations, but also areawide, from individual strata to the entire estuarine and near-coastal region of the state. The target population consists of all coastal waters of Mississippi, including tidal creeks, tidal rivers, tidal ponds, tidal lakes, bays, Mississippi Sound, and waters up to 3 miles beyond the barrier islands. Tidal marsh areas were specifically excluded due to lack of historical data but will likely be added to the design in a subsequent iteration of the monitoring program. Using the USEPA Generalized Random Tessellation Stratified (GRTS) program, 125 locations were selected for a 5-year rotation (25 sites per year), and distributed among waterbody categories as bays/inland estuaries (n=40), open water/Mississippi Sound (n=52), open water beyond barrier islands (n=15), tidal creeks and rivers (n=13), and tidal ponds and lakes (n=5). The goal of the monitoring network design is to be the spatial framework for application of the GBI-MS, and to obtain an unbiased estimate of biological condition for Mississippi waters. Several features of the monitoring results will be reviewed.
Presenter Bio: James Stribling is a director and senior aquatic biologist in Tetra Tech’s Center for Ecological Sciences, located in Owings Mills, Maryland. He received his Ph.D. in 1986 from The Ohio State University, where he specialized in entomology, systematics, taxonomy, and evolutionary biology, primarily focused on two families of terrestrial and semiaquatic beetles. In his ~28 years at Tetra Tech, Dr. Stribling has focused on developing and testing biological assessment protocols and indicators, devising and implementing tests of data quality, and procedures for effective communication of ecological assessment results.
HABITAT, WATER QUALITY, AND COASTAL RESILIENCE IMPROVEMENTS IN MISSION BAY, SAN DIEGO, CA
Astrid Vargas Solis, Moffatt & Nichol
Co Authors: Christopher Webb, Matthew Valerio, James Arnhart
Mission Bay is a 2,299 acres estuary in San Diego, CA, constructed between the 1940s and 1960s with the purpose of developing the largest mand-made aquatic park in the country (Mission Bay Park). Unintended consequences of the man-made bay have arisen overtime, including declining water quality, limited habitat value, and coastal erosion.
The Mission Bay Park Improvement Fund was created in November 2008 to complete a series of capital improvement projects in Mission Bay Park. These projects include efforts to restore wetlands, wildlife habitat, and other environmental assets; maintain hazard free navigable waters, restore shorelines and embankments; and improve the overall conditions of the Park for the benefit and enjoyment of residents and visitors.
Preliminary design is currently underway for prioritized projects which include: Restoration and protection of the shoreline at ten sites of concern along the Bay; expansion of an existing wetland and creation of three new wetlands sites, encompassing a total area of approximately 130 acres; and implementation of modifications of the existing landforms to improve water quality in the back bay, where poor tidal circulation prevents rapid flushing of contaminants. This presentation will provide an overview of considerations for these projects, highlighting on innovative solutions to incorporate resiliency to future sea level rise into their design. Particular attention will be given to the study of alternatives for improvement of water quality. A numerical modeling investigation was undertaken to identify the most effective and feasible alternative among proposed modifications, which include implementation of one-way tidal gates, replacement of an existing causeway with an open channel, and creation of new tidal channels through the northern region of a 435 acres Island on the eastern side of Mission Bay.
Presenter Bio: Ms. Vargas Solis joined Moffatt & Nichol in 2016 after earning a Master of Science degree in Coastal and Marine Engineering and Management. Ms. Vargas Solis has worked on projects focusing on analysis of wetland, estuarine and coastal conditions; coastal flooding vulnerability assessments and numerical modelling of wind-waves, swell waves, and tsunami waves, as well as tidal hydrodynamics and transport modeling in fluvial and coastal environments using both 2D depth-integrated models and fully 3D models.
Improving Coastal Resiliency after Superstorm Sandy: Spring Creek Hazard Mitigation Project
Philip Blackmar, HDR Engineering, Inc.
Co Authors: Christian LaPann-Johannessen, Srikanth Gorugantula
Coastal resiliency has been forced into the headlines in the last two decades as the combination of sea level rise and increasing storm intensities have resulted in some of the most costly hurricanes to date. The result has been an increased focus to developing systems and solutions to better protect our coastlines. Further, these systems are targeting nature based systems that can provide ecological benefits in addition to the storm protection they provide. In response to Hurricane Sandy, the New York State Department of Environmental Conservation (NYSDEC) has been awarded a grant from the Department of Homeland Security’s Federal Emergency Management Agency (FEMA) Hazard Mitigation Grant Program (HMGP) for the implementation of Coastal Storm Risk Management (CSRM) measures at Spring Creek South. NYSDEC, U.S. Army Corps of Engineers, National Park Service, and FEMA are working together to restore Spring Creek South, providing CSRM and ecosystem benefits to the Howard Beach community within Jamaica Bay.
The Spring Creek site is located within the borough of Queens, New York and was filled with millions of cubic yards of dredged material during the first half of the 20th century to create developable land but instead served as a sanitary landfill for 30 to 40 years. These past actions profoundly degraded the salt marsh community and habitat at Spring Creek. The site currently contains marsh, dune, grassland, and secondary woodlands that are dominated by invasive vegetative species (e.g., common reed). During Hurricane Sandy storm surge in the community approached 6 feet and damaged approximately 2,000 structures (residential homes, businesses, schools etc.).
The primary purpose of this coastal resilience project is to mitigate damages to the community by re-contouring and repurposing more than 235 acres of land. An important design feature is a 19-foot (NAVD88) berm to further attenuate wave impacts during coastal storm events. Nature-based features such as low and high marsh, freshwater and tidal wetlands, and living shorelines are proposed components of the mitigation project. This presentation will cover the damages from Hurricane Sandy, the overall project need in the area, and the modeling and analysis approach.
Presenter Bio: Mr. Blackmar earned a B.S. degree in Ocean Engineering from Texas A&M in 2011 and a M.S. degree in Coastal Engineering from Oregon State University in 2013.
Between his B.S and M.S. degrees he worked as a coastal engineering intern at HDR Engineering and following his M.S. degree he returned to HDR full time. Mr. Blackmar’s project experience includes engineering design of shoreline protection, dredging, marsh creation/restoration, beach nourishment, and performing numerical wind wave, ship wake, and circulation modeling, and the evaluation of coastal processes and their interaction with structures.
Piloting innovation: Advancing nature-based resilience strategies through strategic partnerships
Brian Leslie, GHD
Co Authors: Danielle Boudreau, Laura Engeman
In the face of a changing climate many coastal communities are striving to be “resilient”. But how do we actually achieve resilience on-the-ground? How do we track the successes and challenges of implementing innovative shoreline management strategies? In response to these questions, organizations across California are coming together to better understand how to monitor and evaluate the implementation of adaptation projects in the context of resilience. Academic institutions, nonprofits, and the private sector are partnering to increase long-term monitoring of projects and to better understand what ecological and sociological metrics indicate successful adaptation to coastal hazards. In particular, many parts of California have limited examples of nature-based solutions leading to a gap in understanding how living shoreline options may increase both community and ecological resilience. By implementing pilot projects, designing effective partnerships to increase monitoring capacity, and sharing lessons learned throughout the region communities are positioning themselves to better prepare for the future by advancing innovative approaches to coastal resilience. This presentation will explore pilot projects working to leverage regional expertise and science to evaluate nature-based solutions to increase resilience. Each of the projects is working to build a set of best practices for increasing resilience by learning from the challenges each project faces in the design, implementation, and monitoring phases.
Presenter Bio: Brian Leslie is a Senior Coastal Scientist and Project Manager for GHD’s Maritime & Coastal group, where he manages inter-disciplinary teams that implement coastal resilience and beneficial sediment reuse projects. Recently, Mr. Leslie has specialized in the design and construction of nature-based and living shoreline techniques for coastal protection. Brian received a Bachelor of Science in Oceanography from the Florida Institute of Technology in 2001 and a Certification in Coastal Engineering from Old Dominion University in 2012. He has 16 years of professional experience within both the public and private sectors in the fields of coastal science and engineering.
Transforming Existing Planning Processes to Meet Your Needs: Space for Community Discussions on Coastal Management Solutions
Kate Skaggs, Michael Baker International
How do you most effectively manage coastal areas today, in the context of current social and economic structures, while at the same time supporting communities prepare for future climate conditions? The answers can’t be found in prescribed planning requirements, but existing processes can be tools used to bring partners together to discover and develop locally-driven options. This session will highlight tools, best practices, and other ideas for finding answers amongst uncertainty. These ideas will include nuances of navigating existing planning processes from the perspective of FEMA’s Hazard Mitigation Plans to consider multiple hazards within a watershed planning area for holistic, resilient, floodplain management. There is exciting momentum on using hazard mitigation plans as a process for discussing water quantity, water quality, and green infrastructure as solutions for stormwater management and flood mitigation strategies. Participants will learn about the potential of HMPs for going above and beyond minimum requirements to include a cross-sector planning team, a robust public outreach strategy, integrated climate science and uncertainty, and robust hazard mitigation/adaptation actions that all work together to reduce the risk of flooding. Examples will highlight how an engaged planning team could support a local government’s participation in FEMA’s National Flood Insurance Program’s Community Rating System, how robust outreach could increase public awareness of the confluence of rivers and coastal areas, integrate future conditions into hazard assessments, develop mitigation actions/adaptation strategies based on local priorities and identities, and could favor natural and nature-based infrastructure solutions. Additionally, through presenting best practices from FEMA Region 10’s multi-hazard approach to Risk MAP, the presentation will cover alternative risk communication strategies, such as storytelling, to reach a wider audience in a more approachable way, encouraging personal mitigation action and ownership of ‘resilience’. An HMP is not applicable to all communities for all solutions and this session will acknowledge limitations, but where feasible, and HMP is encouraged to represent a community’s values, priorities, and powerful stories as one method for developing inclusive, feasible mitigation actions. While hazard mitigation plans, and other planning mechanisms, are multi-hazard, this presentation will have a coastal management focus, presenting ideas in a way that could be relatable for a wide array of communities.
Presenter Bio: Kate supports FEMA Region 10 Risk Analysis Branch through Resilience Action Partners. She has 10 years of experience in coastal management, climate adaptation, hazard mitigation, and partnership building in Maryland and the Pacific Northwest. Most of her work, and professional enjoyment, has been engaging with coastal communities to support their efforts in discussing creative ways of addressing natural hazards. Kate specializes in helping identify existing planning processes that could be leveraged as opportunities for regional and local discussions around identity, priorities, and how to preserve what means the most to a community, going into the future.
Buzzard Point Coastal Protection Plan
Trine Munk, Ramboll
Co Authors: Murat Utku
The Buzzard Point neighborhood is about to go through a tremendous period of development and investment with several new developments planned along the shoreline. However, the Climate Ready DC Plan identified this area as one of the most vulnerable to climate change impacts in the city and much of the proposed development sits within or adjacent to flood hazard zones. Ramboll is providing a comprehensive analysis of the impacts that storm surge and sea level rise pose and a strategy to minimize or mitigate those impacts on future development. Strategies under consideration include a living shoreline, raising the elevation of key areas, or cloud burst strategies for storm water and flood management.
Ramboll, in collaboration with DOEE, created a dynamic hydraulic model simulating both drainage and coastal flooding for a new neighborhood district in South East D.C. in order to provide strategies for climate adapting a hydrologically susceptible and economically important area of development. The technical solution is being developed alongside the conceptual design to ensure that the conceptual solutions have the desired impact on the overall project area. The stormwater measures are coordinated with the riverine measures to ensure a flexible solution for the entire study area. The stormwater masterplan will consist of one overall plan with one to three alternative suggestions.
Presenter Bio: Mrs. Munk has worked with cities across the world to address complex issues of climate resilience through integrated planning, including Copenhagen, New York City and Washington D.C. Mrs. Munk works closely with the cities, both directly, through co-facilitating city-to-city partnerships or providing specialist knowledge through networks, such as C40.
West Coast Ocean Alliance: Shifting Policy & Real Partnerships
John Hansen, West Coast Ocean Alliance
Since 2013, the states of California, Washington and Oregon, along with federal agencies and over a dozen tribal governments have partnered to create a unique forum for regional collaboration around ocean management. Initially organized as the West Coast Regional Planning Body under President Obama’s National Ocean Policy, the group recently transitioned to the new West Coast Ocean Alliance after a change to federal ocean policy under President Trump. This session will highlight the unique aspects of forming this regional ocean partnership, the efforts made to ensure its effective continuation under the current federal administration, and the importance of working relationships between staff. While federal, state and tribal leadership inevitably change, the group has built new links between governments that allow collaboration existing and emerging ocean uses in ways not possible previously. With a focus on transparent decision-making, compatible use of the oceans, effective sharing of ocean data, and strengthened tribal engagement the WCOA has evolved into a fascinating space for discussion and implementation of ocean policy and management in the U.S. This session will provide an overview of the group’s evolution over time, the features of its intergovernmental membership, and a snapshot of the group’s activities in 2019. Special emphasis will be placed on aspects of intergovernmental relations and new approaches to implementing existing laws and regulations. Stakeholder outreach and engagement on ocean issues will also be highlighted, underscoring the importance of how to work with a range of perspectives over a large geographic scale. Finally, the session will highlight the most pressing ocean issues the group is dealing with currently and how it plans to coordinate and engage around them heading into 2020.
Presenter Bio: Since 2013 John Hansen has served as the coordinator of the West Coast Ocean Alliance, initially established as the West Coast Regional Planning Body. In this role Mr. Hansen supports federally-recognized tribal governments, state governments and federal agencies in the region to coordinate and collaborate at multiple scales to better address current and emerging ocean policy and management issues. Before coordinating the West Coast Ocean Alliance, Mr. Hansen coordinated the West Coast Ecosystem-based Management (EBM) Network, a 501c3 organization focused on enhancing local ocean management approaches along the West Coast through stronger region-wide dialogs, and for the State of Washington on aquatic lands policy and management. Mr. Hansen received his B.S. in Aquatic Biology from the University of California at Santa Barbara, and his Master’s of Marine Affairs from the University of Washington. He lives in Lafayette, CA with his wife and two daughters, Georgia and Josie.
Eroding Regulations? Moving Away from the 540-rule and Primary Frontal Dune at FEMA
Christina Lindemer, FEMA Headquarters
Co Authors: Christina Lindemer
Technical credibility has long been a priority within FEMA’s Risk Mapping, Assessment and Planning (Risk MAP) program to support the delivery of Flood Insurance Rate Maps (FIRMs). Without it, map acceptance for both flood insurance purchases and floodplain management is problematic. This has been demonstrated consistently throughout the history the mapping program, where the most contentious resistance is due to accuracy disputes and perceived lack of fidelity. A focus of the Risk MAP program has been to use the best available science and data to deliver accurate and reliable mapping to communities. This has been achieved through rigorous data usage, peer-reviewed modeling, and adherence to mapping standards.
Hurricane Katrina ushered in a new era of coastal program studies, resulting in an enhancement of mapping in coastal influenced areas. A significant effort was undertaken in updating the guidance supporting methods and models used for these coastal studies, vetted through world-renowned subject matter experts in coastal sciences. The modeling utilized in coastal mapping is aligned with state-of-the-art practices, particularly with respect to storm surge modeling, that are used to develop SWELs prior to overland wave modeling and mapping. The process to develop SWELs can take several years, cost millions of dollars, and be computationally intensive. As a result, these aspects of the modeling effort are sought after by the scientific community and other federal agencies.
However, despite the advances in stillwater modeling, erosion is still based on separate modeling methods developed several decades ago. Similarly, the Primary Frontal Dune (PFD) is delineated not from modeling calculations, but through engineering judgment and visual interpretation of topographic and historical data. The disconnect between modeling results and mapped hazards can be perceived by those who review the maps at a community and individual level as an indication of subjectivity and are often the focus of map disputes.
This also creates a large disconnect in technical credibility between two important aspects of a coastal study – storm surge modeling and erosion calculations. There are now more advanced models that couple dynamic physical processes that can allow site-specific, tailored evaluation of erosion hazards. FEMA is exploring using scientifically sound and modernized methodologies to accurately calculate erosion risk, as it is critical to maintaining technical credibility of coastal FIRMs. In addition, as FEMA begins a programmatic shift from a singular hazard frequency shown on a FIRM to a graduated view of total flood risk, there will be a need to review the level of erosion that can occur at multiple storm recurrence frequencies. Creating a thorough profile of risk exposure along the coastline will assist with providing a site-specific, actuarially sound categorization of hazards.
This presentation will highlight some of the issues encountered in applying the current FEMA erosion analysis methodology and delineating the PFD. It will make a case for developing additional guidelines and methods for determining storm-induced erosion and the Primary Frontal Dune. These explorations will be leveraged to help ensure informed decisions are made regarding the resilience of the nation’s coastline to erosional hazards.
Presenter Bio: Christina Lindemer is a coastal engineer at FEMA Headquarters, and previously worked as a project manager of numerous coastal studies at FEMA Region IV.
The effects of subsidy removal on shoreline armoring
Jordan Branham, University of North Carolina at Chapel Hill
Co Authors: Todd BenDor, Nikhil Kaza, Kyle Onda
Significant urban growth in coastal areas due to growing residential, commercial, and tourist demands has transformed the shape and composition of shorelines. This development relies on a number of factors to remain viable, including public funding for infrastructure, such as roads or utilities, as well as funding for shoreline protection features to guard against natural hazards (e.g., storm surges, sea level rise).
In this paper, we seek to understand how federal flood insurance and infrastructure subsidies affect the development and placement of coastal protection infrastructure. More specifically, we ask, how does the removal of these subsidies affect the location, extent, and composition of coastal protection infrastructure?
We contextualize our work through the lens of the 1982 U.S. Coastal Barrier Resources Act (CoBRA, Public Law 97-348), which aimed to disincentivize risky development in high-hazard areas by removing federal funding for infrastructure and disaster assistance on undeveloped barrier islands (called CBRA units) along the eastern and gulf coasts of the United States.
To understand the impacts of the relatively novel, “subsidy removal” policy approach (Jones 1991), we use a quasi-experimental, pre-post design to assess changes in the composition and location of the coast over time and its relationship to CoBRA units. Along with current, GIS shoreline composition data, we use high resolution satellite imagery to digitize historic shoreline data to assess shoreline change in four states (Alabama, Delaware, Florida, and Texas) across multiple time periods, including before (1980) and after (2015) CoBRA implementation. Shorelines are classified by CoBRA designation (within or outside a CoBRA boundary) and land composition (rock, sand, riprap, tidal flat, marsh). Difference-in-difference tests are used to evaluate the change in shoreline composition over time based on different federal, state, and local land protections. Our findings illuminate the degree of variation in shoreline change between CoRBA units and non-CoBRA areas and provide insights into the relationship between the composition of a shoreline, its nearby development pressure, and the impacts of CoBRA as a subsidy removal approach to hazard management. Initial results suggest that CoBRA was generally effective in limiting the armoring of shorelines.
Studies examining interactions between the built environment and sensitive coastal resources have emphasized macro-scale system dynamics in coastal regions (Timmerman and White 1997) and micro interactions at the habitat scale (Bulleri and Chapman 2010). While shoreline dynamics are the result of a number of influential, natural and anthropogenic forces, we hypothesize that the differential application of hazard reduction conservation-oriented policies may play a major role. While recent work has discovered substantial human modification of shorelines (i.e.,Gittman et al. 2015, 2016), few studies have actually looked at the rates of change to shorelines in light of conservation policy (e.g., CoBRA) or development patterns.
In this paper, we seek to understand how federal flood insurance and infrastructure subsidies affect the development and placement of coastal protection infrastructure. More specifically, we ask, how does the removal of these subsidies affect the location, extent, and composition of coastal protection infrastructure?
We contextualize our work through the lens of the 1982 U.S. Coastal Barrier Resources Act (CBRA, Public Law 97-348), which aimed to disincentivize risky development in high-hazard areas by removing federal funding for infrastructure and disaster assistance on undeveloped barrier islands (called CBRA units) along the eastern and gulf coasts of the United States.
To understand the impacts of the relatively novel, “subsidy removal” policy approach (Jones 1991), we use a quasi-experimental, pre-post design to assess changes in the composition and location of the coast over time and its relationship to CBRA units. Along with current, GIS shoreline composition data, we use high resolution satellite imagery to digitize historic shoreline data to assess shoreline change in five states (Alabama, Delaware, Florida, North Carolina, and Texas) across multiple time periods, including before (1980) and after (2015) CBRA implementation. Shorelines are classified by CBRA designation (within or outside a CBRA boundary) and land composition (rock, sand, riprap, tidal flat, marsh). Difference-in-difference tests are used to evaluate (1) the change in shoreline composition over time, and (2) locational shoreline change. Our findings illuminate the degree of variation in shoreline change between CRBA units and non-CBRA areas and provide insights into the relationship between the composition of a shoreline, its nearby development pressure, and the impacts of CBRA as a subsidy removal approach to hazard management. We also explore edge effects at CBRA boundaries, which offer further lessons regarding the unintended effects of having abrupt edges to zones of subsidy removal.
Studies examining interactions between the built environment and sensitive coastal resources have emphasized macro-scale system dynamics in coastal regions (Timmerman and White 1997) and micro interactions at the habitat scale (Bulleri and Chapman 2010). While shoreline dynamics are the result of a number of influential, natural and anthropogenic forces, we hypothesize that the differential application of hazard reduction conservation-oriented policies may play a major role. While recent work has discovered substantial human modification of shorelines (i.e.,Gittman et al. 2015, 2016), few studies have actually looked at the rates of change to shorelines in light of conservation policy (e.g., CBRA) or development patterns.
Presenter Bio: Jordan Branham is a second-year doctoral student with a specialization in land use and environmental planning in the Department of City and Regional Planning at the University of North Carolina at Chapel Hill. His research interests center around two major areas: coastal climate adaptation and risk management. Currently, he focuses these interests by (1) assessing how major and minor natural hazards impact displacement and (2) examining the determinants of various risk management strategies in coastal areas, such as shoreline armoring or managed retreat.
A Small Community’s Approach to Big Issues
Christopher Layton, Town of Duck
The Town of Duck, North Carolina, is a small vacation community that is home to approximately 400 permanent residents living alongside a community of highly engaged second homeowners and business owners. Many members of this community are involved in Town Council meetings; Town projects and events; and volunteer their time to serve on committees and in support of local programs. The relationship that the Town staff and council members nurture in Duck played a key role in the successful planning and execution of the 2017 beach nourishment project and in continued support for beach maintenance.
Prior to entering the planning phase for beach nourishment, the Town had committed to dune and beach maintenance, providing assistance with sand fencing, dune grass planting, and permitting of projects such as beach pushes. As the commitment to maintenance grew to the exploration of a beach nourishment fill project, staff and elected leaders defined their community approach to the project and the methods needed to find support from a diverse group of stakeholders.
This presentation will discuss how Town of Duck leaders met their community’s expectations and needs with a focus on defining the purpose, expected outcomes, and reasonable costs of the project and how they successfully engaged the community in the decision-making process during all phases of the 2017 beach nourishment project. Relying on open discussion backed by beach analysis data, Town staff communicated a clear justification for the municipal service districts, funding, and future of beach maintenance in the Town of Duck, resulting in informed and engaged community support.
Presenter Bio: Christopher James Layton has served as the town manager of Duck since 2002. Mr. Layton received a Bachelor of Arts in History from the College of William & Mary and a Master of Public Administration from Virginia Commonwealth University. He is a 2006 graduate of the University of Virginia’s Weldon Cooper for Public Service Senior Executive Institute, a 2012 graduate of the UNC School of Government’s Public Executive Leadership Academy, and is one of 1400 public executives to have a earned Credentialed Manager status from the International City Managers’ Association.
Equal Protection vs. Equal Sand: Designing for Equitable Storm Damage Reduction within a Community
Kenneth Willson, APTIM
Co Authors: Kenneth Willson
The Town of Duck is a vacation destination community located in northern Dare County, North Carolina. In 2011, following severe hot spot erosion experienced along a portion of the Town’s approximately 6-mile shoreline, the Town embarked in a feasibility assessment to determine erosion mitigation options. The feasibility assessment concluded that a beach nourishment project along a 1.6-mile portion of the shoreline was the most feasible option.
In order to build Town-wide support for a project that only covered a portion of the Town, APTIM project managers and engineers worked with Town staff to develop a method of assessing need for beach nourishment that was transparent, equitable, and easy to understand. Ultimately, the beach nourishment project and the funding mechanism was approved. The funding mechanism included a combination of County funds generated by a room accommodations tax, a modest increase in the ad valorem tax rate across the Town, and ad valorem taxes generated within a municipal service district that covered the project area. A similar method of designing for equal protection vs. equal sand, has been used by APTIM for two other Dare County Towns.
Though not an entirely novel approach to designing beach nourishment projects, this approach is often misunderstood by local officials and property owners. This presentation will discuss some of the basic methods of the design analysis and how the project team worked to educate the public on how the assessment was performed and what the project was expected to accomplish. Furthermore, the presentation will discuss how the design method continues to be used to assess the entire Town shoreline, not just the portion along which beach nourishment was conducted, to ensure the community maintains equal protection into the future as conditions change.
Presenter Bio: Ken Willson is a client program manager for APTIM. Since 2003, he has assisted coastal clients in Massachusetts, Virginia, North Carolina, Florida, Louisiana and Texas on a variety of coastal management projects. His broad knowledge base of coastal geology, engineering, environmental science, policy, and finance has allowed him to assist numerous clients with designing, permitting, and constructing a wide array of coastal management projects. Mr. Willson resides in Wilmington, North Carolina with his wife Ali and their four (4) children.
Sharing Information During Beach Nourishment: Relationship Building and Communication Methods
Betsy Trimble, Town of Duck
The Town of Duck, North Carolina, is a small vacation community that is home to approximately 400 permanent residents living alongside a community of highly engaged second homeowners and business owners. Although many beachfront communities consist of a wide variety of stakeholders that must be reached, the Town of Duck laid the groundwork for a successful project before the first beach survey.
The Town of Duck has historically worked to maintain relationships with oceanfront property owners, which smoothed the way for beach nourishment project planning. Significant time was spent meeting with owners during the pre-project period to discuss impacts. Staff met with property owners as often as needed to obtain hold-harmless agreements, easements, and to maintain those easements in perpetuity. Often, this involved adapting communication methods to meet community and individual needs. Property owners had access to maps, could request staff to stake areas of their property for a visual reference, and could work with staff via phone, email, or face-to-face meetings. During the active phase of the project, the Town provided daily email updates, online project maps, and photo and video documentation of the progress. With a further personal touch, staff often contacted homeowners once construction was completed at their property with updated photos to keep lines of communication open.
This presentation will detail how each style of communication aided stake-holder engagement and how adapting to the needs of individuals changed the minds of hold-out property owners.
Presenter Bio: Betsy Trimble is the Assistant Public Information Officer for the Town of Duck and has a Bachelor of Arts degree in Historic Preservation from Mary Washington College. She has been with the Town for three and a half years and was responsible for community outreach during the 2017 beach nourishment project. Betsy enjoys working with people and has always lived on the coast where she enjoys working on projects and activities dedicated to preserving the coastline.
Preservation of Coastal Areas Through Community Participation
Sandy Cross, Town of Duck
The Town of Duck, North Carolina, is a small vacation community that is home to approximately 400 permanent residents living alongside a community of highly engaged second homeowners and business owners. These stakeholders were the basis of the community approach used by the Town of Duck when planning and implementing the 2017 beach nourishment project. Staff surmised that the community would like to stay involved and engaged as the project entered the post-construction monitoring phase and ultimately, the planning of a maintenance project.
As discussed in associated abstracts, the Town’s commitment to beach and dune protection existed prior to the nourishment project. The existing beach management program utilized contracted sand fencing and beach grass planting to maintain dunes and encourage dune building. After the nourishment project, this program’s scope was lacking due to the amount of additional sand. Continuing the Town’s commitment to a community-based approach, staff created a successful volunteer planting program by soliciting community involvement, easily closing the gap between the contracted program and the needs of the nourished beach.
This presentation will report the methods used to plan, organize, and complete a successful volunteer beach planting program. The presentation will also discuss the benefits to the volunteers, including community engagement and community building, hands-on investment in the Town’s nourishment project, and an ever-growing understanding of the shoreline environment.
Presenter Bio: Sandy Cross is the permit coordinator for the Town of Duck and has been with the Town for 15 years. She graduated from the University of Maryland and serves the Duck community as a certified zoning official, floodplain manager, and a CAMA local permit officer. Sandy is an avid beachgoer and has a passion for preserving beaches by promoting community involvement.
A New Framework for Near-Bottom Nearshore Currents Based on Measurements at the USACE Field Research Facility
Nikole Ward, Taylor Engineering Research Institute (University of North Florida)
Co Authors: Donald T Resio
Several sets of near-bottom current data were collected over a period of 8 years at the U.S. Army Corps of Engineers Field Research Facility in Duck, North Carolina. This data set consisted of currents measured at up to three elevations above the bottom at deployment depths of 5 meters, 8 meters and 13 meters, as well as continuous real-time wind and wave data collected at the pier. The data has been recovered from previously encrypted files, and has now been collated, quality checked and analyzed to define a climatology of near bottom currents along the study area using current moments. A major reason why the data set had not been previously available for analysis was the format of the data combined with the large effort required to subject them to rigorous processing and quality control. The analyses conducted in this presentation represent the first ever attempt to analyze this type of data on this scale.
An initial monthly investigation was conducted at the 8-meter site to determine driving forces of mean currents and construct a seasonal investigation to quantify relationships between the cross-shore currents and different forcing mechanisms. Once seasonal trends were established relating mean current to incident wave height, wave steepness and wind speed, an examination of some significant historical events within the study was completed to help link cross-shore current behavior to storm events. Three separate nor’easter events and three significant hurricanes (Bonnie, Dennis and Floyd) were found to produce very significant cross-shore currents at the study site. Similar to previous nearshore studies, it was found that the occurrence of onshore winds higher than about 12 m/sec and significant wave heights greater than about 1.5 meters produce near-bottom mean currents moving in the offshore direction. Alternatively, when winds are blowing in the offshore direction, waves are still propagating onshore, but mean near-bottom currents tended to be directed in the onshore direction, particularly when accompanied by low-steepness waves.
The importance of pronounced vertical current structure within the water column was evident, even though the instruments’ measurement elevations were often all located within the bottom boundary layer. In contrast to the assumption of zero cross-shore mean currents at near-coast sites implicit in two-dimensional depth averaged models used in most coastal engineering studies today, it was found that cross-shore near-bottom currents are rarely ever zero. Depth-averaged models inherently assume that currents move as a single block of water throughout the water column. The physical impacts of this misrepresentation of nearshore currents become very significant in predictions of many coastal phenomena, such as storm surge, sediment transport and wave conditions at the coast.
When wave heights exceed 2 meters, mean currents tend to be between 0.2-0.5 meters per second in both the onshore and offshore direction, in the opposite direction of the primary forcing at the surface. In some instances, wave heights are low with strong mean currents while wind speeds are high, indicating the driving force in this situation is wind speed. However, there are cases where wave heights are large and mean current values are relatively low, which requires further investigation. Future work will include investigating phenomena that are related to higher-order odd moments of the current statistics, since they are expected to play a critical role in improved understanding of the physics within the nearshore and are very much needed for predictions of coastal evolution under future sea level rise and potential climate change.
Presenter Bio: Nikole Ward is a Ph.D. student within a joint program between UF and UNF working on nearshore circulation and sediment transport. She received her Master’s in Coastal Engineering
at UNF in August 2018.
Seasonal and interannual variability of swash-zone sand-habitat biogeochemistry: Time-series monitoring in Long Bay, South and North Carolina
Angelos Hannides, Coastal Carolina University
High-energy sandy shores, such as those of Long Bay, South and North Carolina, play an important role to the economic and ecological health of the region. Evaluating the state of our sandy shores and vulnerability to external impacts requires an understanding of interdisciplinary baseline conditions. Data must be collected with regularity, i.e., over a time series, to capture natural variation due to seasons, tides, weather, etc. Knowledge of baseline conditions allows a more precise investigation of living and non-living processes underlying and dictating those conditions. Ultimately, this knowledge can be used to gauge the impacts of human activities and natural disturbance events on the health and function of this important coastal zone type.
The sand biogeochemistry research program was established at Coastal Carolina University in fall of 2016 with the above goals in mind. It is the brush with which we have started painting a comprehensive baseline picture of the conditions at sandy beaches and how they vary over natural cycles. We have been applying our continuously enhanced interdisciplinary observational and analytical methodologies on swash-zone sand biogeochemistry at a monthly time-series at the Anne Tilghman Boyce Coastal Reserve (Waties Island) since November 2016, and a set of seven additional sites, from Pawleys Island, SC, at the south end to Caswell Beach, NC, at the north, occupied on a quarterly or intermittent basis since the summer of 2017.
We present seasonal and interannual patterns in physical (e.g., permeability, porosity), geological (e.g., grain size and surface area, sedimentary composition), chemical (e.g., oxygen, carbon, nitrogen, phosphorus) and biological (e.g., organic matter, chlorophyll a) properties and parameters, that characterize a gradient across space and across master-properties, such as permeability, that dictate primary productivity and nutrient cycling. We discuss the implications of our findings on the ability of sandy shores to process land-derived material, supplied by humans or by natural processes, such as hurricanes and floods, and the needed time for (re)nourished beaches to reestablish their baseline biogeochemical character.
Presenter Bio: Angelos Hannides is an Assistant Professor in the Department of Marine Science at Coastal Carolina University. His major research focus is on nearshore permeable sediments and the interactions of physical forcing, biotic processes and organic matter cycling that determine their function and ecosystem services. He also has a long-term interest in biogeochemical sensors and their applicability and performance on various deployment platforms.
Does the Equilibrium Beach Profile Theory Still Fit New Jersey Beaches?
Jon Miller, Stevens Institute of Technology
Co Authors: Adam Sissson
(Brunn, 1954) became the first to empirically identify the 2/3rds power law relationship between offshore distance and depth (h=Ay2/3) which has become known as the equilibrium beach profile. (Dean, 1977) confirmed the empirical results obtained by Bruun by analyzing 502 beach profiles from the Atlantic and Gulf coasts of the United States. Among these were 42 profiles in New Jersey. (Dean, 1991) showed that the result could also be obtained theoretically by assuming the profile shape was related to the ability of a given grain of sand to withstand a certain amount of wave energy dissipation per unit volume. The present work was inspired by recent anecdotal observations that single grain size equilibrium beach profiles typically do not fit New Jersey beach profiles well. The general observation is that either the nearshore or the offshore can be fit, but that in doing so, the fit of the opposite end is severely compromised.
The analysis to be presented relies upon 27 years of beach profile data collected biannually by Stockton University at more than 100 sites along New Jersey’s ocean and bayfront coastlines. The data is utilized to re-examine the fit proposed by Bruun and Dean, and to examine spatial and temporal trends in the data. Early results indicate that the existing equilibrium beach profile relationship appears to fit the measured data well, but that the typical A values may underestimate the nearshore beach slope for New Jersey beaches. The results also reveal a general decreasing trend in A values between Sandy Hook and Manasquan Inlet (nodal point where the net longshore sediment transport switches direction). Temporal trends will be similarly evaluated and existing relationships between sediment grain size and A and b (exponent) will be reexamined.
Brunn P. Coast Erosion and the Development of Beach Profiles [Report] : Tech. Memo No. 44. – [s.l.] : US Army Coirps of Engineers, Beach Erosion Board, 1954.
Dean R.G. Equilibrium Beach Profiles: Principles and Aplplications [Journal] // Journal of Coastal Research. – 1991. – pp. 53-84.
Dean R.G. Equilibrium Beach Profiles: US Atlantic and Gulf Coasts [Report] : Report No 12. – Newark, DE : Department of Civil Engineering, University of Delaware, 1977.
Presenter Bio: Dr. Miller is a Research Associate Professor of Coastal Engineering in the Department of Civil, Environmental, and Ocean Engineering at Stevens Institute of Technology. Dr. Miller received his Bachelor’s Degree in Civil Engineering from Stevens in 1999 and a Masters and Ph.D. in Coastal Engineering from the University of Florida in 2001, and 2004 respectively. While at Florida, Dr. Miller received a Fulbright Post-doctoral Fellowship to study at the University of Queensland in Brisbane, Australia. Dr. Miller currently serves as the New Jersey Sea Grant Coastal Processes Specialist and Director of the New Jersey Coastal Protection Technical Assistance Service (NJCPTAS).
Panel Discussion: Lessons from Structuring Outcomes-based Transactions for Flood Infrastructure
Shannon Cunniff, EDF
Outcomes-based financing is proving to be a compelling, new and innovative means for local governments to pay for resilience infrastructure projects needed to address complex climate change, resilience and flooding challenges. More specifically, cities are issuing Environmental Impact Bonds as a means to financially de-risk much-needed innovative infrastructure projects by connecting bond buyer returns directly to the performance of the projects. If innovative projects achieve or exceed their intended outcomes, everyone wins, including citizens/ratepayers, government issuers and investors. If projects underperform expectations, then investors share in that loss with the city. The implications of structuring EIBs are profound and include enhanced community engagement, project design, project evaluation and ongoing public communications about project success in terms of outcomes achieved. This panel brings diverse experience and expertise in the policy and practical implications of structuring outcomes-based infrastructure transactions to the urgent conversation field of preparing for the implications of a changing climate.
Presenter Bio: Shannon Cunniff, recently retired from Environmental Defense Fund where she was the Director of Coastal Resilience and advocated for using natural infrastructure solutions as part of community efforts to build resilience to floods and storms. Shannon has been working on ways to accelerate adoption of natural infrastructure solutions by developing planning and design guidance, exploring innovative financing, and influencing development and implementation of federal policies. Prior to EDF, she worked 27 years for the federal government — specifically the USACE, EPA, DOI, and DoD – on issues at the intersection of water resources engineering, risk management, and environmental policy.
Todd Appel, Quantified Ventures
Presenter Bio: Todd brings decades of experience in organizational transformation, performance management, and multiparty deal structuring, working with numerous government departments in the U.S. and Europe. As Managing Director, Todd leads client delivery across all of Quantified Ventures business verticals. He has led the launch of several Environmental Impact Bond projects, including closing the first publicly offered EIB with Atlanta. He focuses on utilizing outcomes-based financing to deploy green infrastructure and other resilience investments, improve energy efficiency, address water quality issues through on-farm management practices, and promote sustainable urban wood economies. Prior to Quantified Ventures, Todd led projects domestically and internationally for IBM and PriceWaterhouseCoopers. He is based in Boulder, Colorado – the perfect place for a nature lover like him to bike, hike, and ski.
Brian Joyner, Moffatt & Nichol
Design and Construction of the Little Beaver Island Shoreline and Coastal Wetland Habitat Improvement Project at Beaver Island State Park
Matthew Henderson, Anchor QEA
Co Authors: Ryan Davis, Ram Mohan, Mark Bogdan
Beaver Island State Park is a 950-acre park at the south end of Grand Island in the upper Niagara River in New York. The park is owned and operated by the New York State Office of Parks, Recreation, and Historic Preservation. The proposed project covers approximately 800 linear feet of shoreline and nearshore habitat along a high-energy section of the Niagara River. Erosive forces, including high velocity currents, wind energy, and ice scour acting along the shoreline, prevent the establishment of coastal wetland habitat and have led to extreme bank erosion and property loss.
The project sponsor, Buffalo Niagara Waterkeeper, identified stabilizing and enhancing this portion of Little Beaver Island as a top priority for improving habitat for rare, threatened, and endangered species, as well as for its potential contribution to the de-listing of the Niagara River as an Area of Concern.
Project designs were initiated in mid-2018. The design objectives included creating and restoration riparian and coastal habitat to improve ecological conditions for resting, feeding, and spawning habitat for numerous fish and wildlife species, and enhancing shoreline stability to prevent future property loss by addressing erosive forces and improving coastal resiliency. To meet these objectives, stabilization and restoration designs were developed that included offshore breakwaters to reduce wind-driven wave energy and provide offshore tern nesting habitat. A hydrodynamic and wave model of the area was developed to evaluate erosive forces acting across the living shoreline under various storm events and typical conditions. Inshore of the breakwaters, coastal wetland and riparian habitats were designed to improve habitat diversity and support native species.
Permitting was completed in fall 2018 and construction started in late 2018 and is expected to be completed in spring 2019.
In this presentation, we will review the coastal and habitat restoration design and lessons learned during construction of the project.
Presenter Bio: Matthew Henderson has more than 25 years of experience as a coastal and environmental engineer, focusing on evaluating coastal conditions and developing sustainable approaches and designs to ensure stability of shorelines, coastal infrastructure, and natural resources. His expertise includes hydraulics and hydrodynamics, coastal engineering, living shoreline designs, beneficial use of dredged material, hurricane surge modeling, wave modeling, riverine flood modeling, and sediment erodibility and stability assessments. He has performed shoreline erosion and protection designs for waterfront and restoration projects throughout the United States.
Shoreline Engineering with Cobble Material
Conor Ofsthun, Moffatt & Nichol
Co Authors: Brian Leslie
Southern California is known for its wide, sandy beaches. However, this is not the natural state which these beaches equilibrate towards (Flick 1993). These beaches are naturally narrow. Even when a sand supply is present, a stormy winter season often erodes a sandy beach and exposes a natural underlying cobble beach.
Sea level rise threatens to eliminate up to two-thirds of southern California’s beaches by year 2100 (Vitousek et al. 2017). Fine sand is the first to erode, leaving coarser material behind, such as cobble. Coarse sediment tends to form steep reflective beaches with offshore, submerged sand storage (Wright and Short 1984). This is the direction that southern California beaches may be heading.
Cobble material, with a grain size of 64 to 256 mm (Wentworth 1922), is known to better maintain its position in the face of storms (Bradbury and Powell 1992). An opportunity exists to engineer shorelines with cobble material to maintain beaches under threat of sea level rise and storm waves. Several past studies have tackled such an opportunity. Everts (2002) identified a tendency for cobble berms to accrete during winter wave climates and lose volume during the summer. This research found near zero net alongshore transport of cobble material and hypothesized that cobble management could minimize coastal erosion. Furthermore, Allan and Hart (2007) found cobble berm construction in front of an artificial dune to be protective in the face of major storms, and resilient to periodic overtopping.
Design parameters for an effective cobble berm are currently being worked out by scientists and engineers through on-going projects (Philip Williams & Associates 2005, Komar and Allan 2010, ESA 2016, M&N 2017). For example, Moffatt & Nichol designed a buried revetment and sand dune to be fronted by a total of approximately 2,000 CY of repurposed on-site cobble. The construction of this project was completed in Spring 2019 and will undergo a rigorous 5-year monitoring program to assess and adapt its design components.
Certain concerns exist with the use of cobble for shoreline management that should also be considered. One is the damage that loose cobble can do to infrastructure and structures if thrown shoreward during storms. Also, cobble can litter coastal roadways and require extensive removal operations. In addition, cobble in small deposits along the base of coastal bluffs can actually accelerate erosional notching of the base of the bluff, triggering more rapid bluff failure and landsliding. Finally, cobble beaches are relatively habitat deficient and present little benefit to the beach ecosystem as compared to sand beaches.
In southern California, retaining sand beaches and providing coastal protection will become increasingly difficult. Cobble material can improve the resilience of shorelines by maintaining beach width and elevation during storms. This presentation will cover a literature review of cobble material on the West Coast of the USA, and present examples of integrating cobble material into on-the-ground coastal engineering projects.
Presenter Bio: Conor Ofsthun is a Coastal Scientist with Moffatt & Nichol in San Diego, CA. Brian Leslie is a Senior Coastal Scientist at GHD in San Diego, CA. The two authors work on a wide range of coastal environmental and engineering projects in southern California including beach nourishment, wetland restoration, sea level rise analysis, and coastal development.
Bringing Concrete to Life – Enhancing Natural Processes on Concrete Based Coastal and Marine Infrastructure (CMI)
Andrew Rella, ECOncrete Inc.
Co Authors: Andrew Rella, Ido Sella, Shimrit Finkel
With two-thirds of the human population concentrated around coastlines (Creel, 2003), alongside with threats from sea level rise and increased storminess, coastal development and changes to natural coastlines are inevitable. Unfortunately, too often coastal and marine structures like ports, marinas, and coastal defense structures, take the place of highly diverse and productive intertidal and subtidal habitats, replacing them with barren, unproductive urban habitats. Not only do these hard defenses have significantly lower environmental value compared to natural coastal habitats, they are also less resilient and adaptive compared to natural barriers such as coral or oyster reefs, which organically grow with time.
Following the growing interest in living shorelines and nature-based solution for coastal protection, in recent years a complementary approach of eco-engineering coastal and marine infrastructure has emerged. The latter aims to provide an environmentally sensitive solution in areas that do not allow for living shoreline solution due to heavy urbanization or the lack of horizontal width that they typically require. Eco-engineering solutions strive to enhance the biological performance and ecological value of engineered solutions, without compromising their functional and operational capabilities.
Here we present a more advanced approach, in which eco-engineering aims not only to enhance biological performance for the sake of the environment, but to harness natural processes for increasing the sustainability and resilience of the infrastructure itself. By implementing science based, cost effective design enhancements that are in accordance with the principles of ecological engineering it is possible to modify the design of coastal and marine infrastructure to encourage the increased growth of native organisms, as well as greater species richness (Perkol-Finkel and Sella, 2014). These design approaches have been proven not only to provide significant ecological advantages over traditionally engineered CMI, but also valuable structural advantages; contributing to a structures’ strength, stability and lifespan (Perkol-Finkel and Sella, 2015).
ECOncrete®’s innovative solutions reduce the ecological footprint of ports, marinas, coastal protections schemes and urban waterfront projects, while adding to their structural integrity. Using numerous case studies of ECOncrete’s bio-enhanced concrete elements being implemented in Ports around the world, we provide quantitative data of biocalcification processes and compare them to those developing on standard “gray” seawalls. The case studies to be presented will include bio-enhanced seawalls, ecological tide pool and armoring units, and ecologically enhanced marine mattresses. All findings are based off of comprehensive, multi-year monitoring programs whose results clearly show the ability of bio-enhanced structures to enhance growth of calcifying organisms thus enhancing natural growth of habitat forming species and ecosystem engineers that have the potential to increase the resilience and adaptivity of the structure. In addition to presenting the key results from these case studies, the paper will discuss the key role of multidisciplinary collaborations in such projects, and relate to future implications and knowledge gaps in this emerging field.
Presenter Bio: Andrew Rella is the global Director of Engineering for ECOncrete Tech, a company based in Israel, with operations around the world; offering innovative concrete ecological solutions for marine infrastructure. Andrew’s work focuses around Coastal, Riverine and Environmental Engineering. Previously, Andrew worked as a postdoctoral researcher and lecturer at Stevens Institute of Technology, in Hoboken, NJ. Andrew’s experience includes being a member of the Coordinating Team of the Hudson River Sustainable Shorelines Project since 2009, consulting on pilot projects for the NJ USACE and American Littoral Society, developing workshops for the Departments of Remediation and Environmental Protection, as well as co-authoring the NJDEP Living Shorelines Engineering Guidelines. Andrew has a Ph.D. in Ocean Engineering from the Center of Maritime Systems at Stevens Institute.
Shoreline Protection of Historic and Coastal Resources at Brunswick Town/ Fort Anderson
Randy Boyd, Atlantic Reefmaker
Co Authors: Devon Eulie, PhD
The shoreline at the State of North Carolina’s historic site, Brunswick Town/ Fort Anderson (BTFA), was in need of protection from constant tide forces and dynamic wave action. Colonial-era wharves are being destroyed, and precious artifacts from these buried colonial-era wharves are being washed into the Cape Fear River. The Civil War-era batteries are being undermined. Additionally, valuable Spartina alterniflora marsh platforms were being eroded. The NC Department of Natural and Cultural Resources (NCDNCR) seeks to halt the shoreline erosion in order to prevent the destruction of and additional wash of these buried colonial-era wharves, the Civil War-era batteries and the destruction of three other colonial era wharf sites.
Erosion on the banks of BTFA was first noted in 2008. In 2012, the NCDNCR attempted to arrest the shoreline erosion. The initial attempt was unsuccessful in arresting the erosion, and the NCDNCR struggled to protect these sensitive and historically significant resources from the adjacent high energy wave environment.
The Reefaker concept was identified as a potential solution for the shoreline erosion in place of a traditional breakwater structure. The Reefmaker product provides several ecoservices and works in horizontally limited area whereas the breakwater structure does not provide these services nor would have worked in horizontally limited areas.
In summer 2017, Phase 1 was implemented involving 220’ of RM along the highest eroded area of BTFA. Construction for Phase 2 (240’) was completed in early August 2018, prior to Hurricane Florence battering the project area for several days. The shoreline in these areas has been stabilized, and a new shoreline is being formed as the Reefmaker structure disrupts wave energy and allows for flushing which enables sediment accretion.
The University of North Carolina Wilmington conducts project monitoring for the State of NC. Monitoring components include sediment accretion, vegetation establishment and wave energy measurements; including the approaching wave, wave transmission through the structure and reflected wave energy. UNCW established the project’s baseline documentation in 2016, and began monitoring Phase 1 in August 2017. Quarterly monitoring reports are being generated by UNCW through summer 2018.
This presentation will describe past stabilization methods of the historic site, document why the Reefmaker concept was the best solution for the BTFA site over a rock breakwater structure, note Phase 2 adjustments from lessons learned on Phase I and describe the project’s monitoring results to date.
Presenter Bio: Randy has more than 28 years of experience in hydrologic/hydraulic analysis and design. Prior to joining Atlantic Reefmaker, Randy worked at the North Carolina Department of Transportation (NCDOT) as the Regional Hydraulics Engineer-Region II and at a private engineering firm in Raleigh, NC. He has extensive experience utilizing hydrologic/hydraulic design principles for the completion of a variety of project types. While being tasked to identify a shoreline stabilization method at NC state historic site, he learned of the Reefmaker technology. Over the past 3 years, he has improved the Reefmaker’s capability and applicability in the coastal environment.
Resiliency through Restoration: Implementation and Monitoring of Community-Driven Restoration Projects to Inform Nature-Based Adaptation
Nicole Carlozo, Maryland Department of Natural Resources
Co Authors: Rebecca Swerida, Bhaskar Subramanian, Sasha Land
Natural features can enhance the ability of communities to prepare for and recover from climate change impacts such as sea level rise, storm surge, erosion, and precipitation-induced flooding. Recognizing the risk-reduction benefits of natural features, the Maryland Department of Natural Resources (Department) established a Resiliency through Restoration Initiative in 2017. The Initiative will demonstrate how natural and nature-based features can be integrated into local resilience planning and help protect communities and economies from climate change impacts. Over the past century, mean sea level in the Chesapeake Bay has risen 1 foot and the state expects up to 2 additional feet by the year 2050. Rising waters coupled with sinking land has led to more common sunny-day and stormwater flooding that impacts day-to-day activities across the state. In addition, Maryland has experienced six significant hurricane and flood events over the past decade that warranted Presidential Disaster Declarations, resulting in more than $99 million in federal public assistance. An additional $31 million is expected from 2018 events. The Resiliency through Restoration Initiative is one of many state-led efforts to address community adaptation to these climate impacts. This novel and completely state-funded program provides local governments and non-profits with financial and technical support for design, construction and adaptive management of natural and nature-based resiliency projects through a Community Resilience Grant. Unique to this effort, the Initiative promotes tracking and monitoring of 15 innovative pilot projects to support adaptive management activities and increase understanding of the community benefits of natural adaptation solutions. The Chesapeake Bay National Estuarine Research Reserve (Reserve) is collaborating with the Department to develop a consistent, project-specific adaptable monitoring framework in order to study and possibly improve upon shoreline restoration methods. This presentation will highlight the design, construction and monitoring of a dune restoration and marsh enhancement project in Deal Island, an underserved community on Maryland’s eastern shore. The Deal Island Community Shoreline Restoration and Enhancement Project is the first of the state’s 15 pilot projects to be designed and monitored. It was identified as a top priority by the community through a series of community conversations held through the Deal Island Peninsula Project, a collaborative coastal resilience effort between numerous state, local, community, non-profit, and university partners. In preparation for construction, Reserve and Department staff developed a Before-After Control-Impact (BACI) design monitoring protocol based on the consistent, Initiative-wide framework. Pre-construction monitoring is currently underway to track marsh, shoreline and stone structure elevation, vegetation diversity and density, rates of accretion, and changes in sediment characteristics at the project and adjacent control site. A consistent monitoring effort across this series of innovative, natural and nature based projects will produce a detailed understanding of how restoration can increase community climate resiliency.
Presenter Bio: Nicole is a Natural Resource Resiliency Planner at the Maryland Department of Natural Resources where she manages the state’s new Resiliency through Restoration Initiative. Nicole is responsible for integrating climate data and other technical and spatial information into coastal restoration, conservation, and waterfront enhancement activities. Nicole earned a Masters Degree in Coastal Environmental Management and a Certificate of Geospatial Analysis from Duke University, and a B.A. in Biology & English from St. Mary’s College of Maryland.
Increasing use of natural and nature-based features to build resilience to storm-driven flooding
Pamela Mason, Virginia Institute of Marine Science
Co Authors: Jessica Hendricks, Julie Herman
Community resilience to storm-driven coastal flooding is improved with the presence of natural and nature-based features (NNBFs) such as wetlands, wooded areas, living shorelines, and beaches. In addition to flood protection, these features provide multiple ecologic and socio-economic benefits. We have developed a GIS-based analysis to identify NNBFs in coastal Virginia that allows us to 1) priority rank NNBFs that provide flooding mitigation and co-benefits to buildings, and 2) identify and priority rank areas where the creation of NNBFs could be beneficial for at-risk infrastructure and generation of co-benefits credits. We focus on two of these co-benefits: Community Rating System credits through the Federal Emergency Management System National Flood Insurance Program and water quality services tracked for the Chesapeake Bay TMDL Program and the Virginia Stormwater Management Program. Locality specific results and outreach will enable local governments to make informed decisions regarding existing and future natural infrastructure and engage in funding and implementation partnerships to address multiple needs for coastal resilience.
Presenter Bio: Pamela Mason has been working on coastal resource issues for several decades with a focus on integrated management of shorelines and coastal community resilience. Her current research interest is multiple benefits of natural and nature-based features including tidal and non-tidal wetlands. She has been engaged with the Chesapeake Bay Program for over 20 years serving on the Wetlands Workgroup and 2 BMP Expert Panels: Shoreline and Wetlands (co-chair). She is serving on the Technical Review Team of the Federal Highway Administration Nature-based Resilience for Coastal Highways and the Virginia Coastal Policy Team. She participated in the Technical Workgroup to Virginia Marine Resources Commission supporting the development of two Living Shorelines General Permits for Virginia and was primary author of “Study of Tidal Shoreline Management in Virginia: Recommendations for living shorelines and tidal resources sustainability” report to the Governor and Virginia General Assembly 2010. She has a BS in Biology from the University of Delaware and MS in Marine Science from William & Mary, Virginia Institute of Marine Science.
The US Army Corps of Engineers New Jersey Back Bays Coastal Storm Risk Management Study: An Overview of Current Efforts and Products
J Smith, USACE
The Atlantic Coast of New Jersey is fronted by a Federal Coastal Storm Risk Management (CSRM) program. However, the New Jersey Back Bays (NJBB) study area, which encompasses five counties, approximately 1,300 square miles and 950 miles of coastline, currently lacks a comprehensive CSRM program. As a result, the NJBB region has experienced major flooding impacts and devastation during Hurricane Sandy and subsequent coastal events owing to the low elevation areas and highly developed residential and commercial infrastructure along the back bays coastline.
The purpose of the U.S. Army Corps of Engineers (USACE) NJBB CSRM Feasibility Study is to assess comprehensive CSRM strategies to manage risk to vulnerable populations, property, ecosystems, and infrastructure from coastal flooding associated with storm surge events and future sea level scenarios. CSRM management measures including structural, nonstructural, and natural and nature-based features for the NJBB study area are being considered for inclusion in a Tentatively Selected Plan and draft Feasibility Report scheduled for release in early 2020. An Interim Report was released in March 2019 which presents a focused array of alternative plans that manage risk and reduce damages from coastal storms as well as the associated engineering, economic, social, and environmental analyses. The Study will likely conclude in 2022.
A particular emphasis has been placed on coordinating and collaborating with Federal agencies, NGOs, municipal entities, stakeholders and the general public to facilitate community coastal resilience in a systems context and to ensure consistency with other plans, projects and programs. Several stakeholder and public meetings have been held which have been instrumental in defining study context and scope. The New Jersey Department of Environmental Protection is the Study’s non-Federal Sponsor.
Presenter Bio: J. Bailey Smith is a Regional Technical Specialist with the U.S. Army Corps of Engineers (USACE) Coastal Storm Risk Management Planning Center of Expertise and the Philadelphia District. Mr. Smith is the project manager for the New Jersey Back Bays Focus Area Study and has contributed to the post-Katrina restoration studies in Louisiana and Mississippi. Mr. Smith oversaw the Delaware Estuary Regional Sediment Management Plan and previously worked at the USACE Engineer Research and Development Center in Mississippi.
The use of Geosynthetic Mattresses for Coastal Protection
Robert Creel, HUESKER INC
Huesker originally created the Incomat Geo-synthetic Mattress system as a fabric form work for concrete mattress. Since the needs of coastal protection have evolved since the early 1960’s we adapted our product to be able to use native materials while still taking advantage of the consolidation and confinement provided by the geo-synthetic. The use of a Incomat Sand Mattress dune capping system can greatly reduce the amounts of dredge material needed for beach re-nourishment by providing a uniform container that can act as a secondary protection layer to the dune itself. We can use this system in conjunction with our Dune Core tubes for added strength as well.
Presenter Bio: Robert Creel has worked for HUESKER Inc. since 2013. He came on board as a Regional Sales Manager after graduating from Clemson University. When given the opportunity to bring the hydraulics and coastal protection products to the States Robert could not wait to get started.
Local Funding for Coastal Projects: Policy, Consideration, and Practices
Annie Mercer, ASBPA
The ASBPA local funding white paper attempts to identify project considerations and tools available as a resource for local officials daunted by the challenges of funding coastal projects.
Increases in storm severity and damage bring awareness to the need for creating, continuing, and sharing cost on coastal projects. Funding as a response to storm related damage is not enough. Therefore, proactive projects are becoming more common. Shore protection legislation commenced in the 1950s evolving to the storm-based funding seen in the past 20 years post-Katrina. Funding practices have seen a similar evolution through the years beginning with the Water Resources Development Act (WRDA). Large scale projects are seeing efforts to expedite funding while smaller local and regional projects may not see this speed unless they invest in their own preliminary studies. Evolutions in policy gives local officials the agency to make big decisions about how to manage and fund their projects.
Considerations for towns to examine before funding decisions are made include: community characteristics, regional characteristics, and funding partnership opportunities. Communities should assess the nature of their beach’s population, its density, nature of building style, among others. Legal considerations from federal and state legislation to town ordinances should be consulted. Regional considerations on the type of the shoreline, type of environmental disasters the project would encounter, or sand source availability need to be evaluated for assessing the total cost of projects. Finally, local officials need to be aware of federal, state, or municipal partnerships available for minimizing financial strain.
Coastal projects have a multitude of funding options at the local, municipal, and regional levels. Beach officials can access funds through special taxing districts, inlet management districts, erosion control districts, tourism taxes, sales and use taxes, parcel assessments, Metropolitan Planning Authorities, joint power authorities, geologic hazard abatement districts, different bonds, and parametric insurance.
This presentation will focus on informing the audience about the white paper. There will be a brief overview of policy and funding history for coastal projects. The overview will be followed by a discussion of considerations towns should discuss before making funding choices. The main portion of time will be dedicated to introducing the different tools available to fund projects and case studies of successful implementation of tools.
Presenter Bio: Annie Mercer, ASBPA Intern
Ms. Mercer served as a Government Affairs intern during the summer of 2019 managing the Local Funding white paper. She has a Masters in Forensic and Legal Psychology with a concentration in Intelligence Studies from Marymount University and received her Bachelor of Arts in Psychology from Hood College. She has worked on the beach installing vegetation since 2005 with her father’s company Coastal Transplants. Now she is working as a Project Coordinator for the company.
Financing Coastal Resilience
Dan Ginolfi, Coastal Strategies, LLC
Co Authors: Dan Ginolfi, Howard Marlowe
In 2019, almost every community in the nation has a FEMA approved local hazard mitigation plan, but similarly, almost every community struggles to find ways to implement for two reasons: evaluation of alternatives and cost. In order for communities to advance from planning to implementation, they must have the resources, skills and knowledge to make informed decisions to better their region in preparedness and response to disasters and severe weather events, and the capital to finance it. New flood risk maps are being released, new reports are providing data on the costs of disasters and the costs of mitigation and new technologies are being developed that are solutions to problems communities are facing today. However, the greatest problem remains funding. The National Institute of Building Sciences has concluded in their 2018 report, Natural Hazard Mitigation Saves: Utilities and Transportation Infrastructure, that every $1 invested in resilient infrastructure that complies with the 2018 International Residential and Building Codes provides a national benefit of $11. So, the question persists, why has the United States waited so long to implement projects after hundreds of billions in damages have directly affected its economy? The answer is cost. And the time to invest is now. With sea level rise and climate change literally knocking down doors, Coastal Strategies has risen to tackle the initiative of finding institutional investment for private, local and regional projects. Local businesses, corporations, utilities, banks, insurance agencies as well as the local and state governments have a vested interest in their local economies – when it floods and storms, everyone loses business. When properties lose value due to flooding, it cripples the local tax base, further crippling the ability to invest further into resilience projects. The issue goes far beyond flooding, with high winds, drought, and storm surge, utilities and other critical infrastructure are likely to be damaged or destroyed. Before material science and manufacturing technology enabled us to develop robust and resilient designs, rebuilding was intense, but not nearly as costly. The number of developments along bodies of water has exploded in the past two decades, with nearly 50% of every person in the US living within 50 miles of the coast, whether it is the Great Lakes or on of the nation’s ocean-facing coasts. So the question is what can we do to protect it?
Presenter Bio: Two-person presentation:
Dan Ginolfi is the Director of Coastal Resilience for Coastal Strategies. Dan works with local governments, businesses and nonprofits to identify, plan, finance and implement coastal resilience projects. He currently serves as a consultant to the Army Corps of Engineers’ Institute for Water Resources and also works as Policy Advisor at Warwick Group Consultants. Dan serves as a lead researcher on innovative water resources solutions in energy, finance and sustainability. He is a graduate of James Madison University and has a degree in Engineering with a focus on systems engineering, environment and sustainability.
Howard Marlowe is President of Coastal Strategies and Warwick Group Consultants. He has over 36 years of experience as a coastal advocate for state and local governments on projects, studies and policies related to the nation’s water resources. He specializes in the policies and procedures of the US Army Corps of Engineers as well as other Federal agencies who provide technical and financial assistance related to coastal resilience. As a recognized expert in coastal resilience, he has appeared on CNN, CBS-TV, Bloomberg TV, and many other media outlets and has been the subject of articles in The New York Times, The Wall Street Journal, Bloomberg BusinessWeek, The Washington Post and more than two dozen other publications. Mr. Marlowe is a graduate of the University of Pennsylvania’s Wharton School of Finance and Commerce as well as New York University’s School of Law. Currently, he is also a member of the Adjunct Faculty at the George Washington University’s Graduate School of Political Management.
Weighing the benefits of a federal versus locally sponsored beach management program; a lesson in funding, schedules, and uncertainty from Pawleys Island, SC.
Steven Traynum, Coastal Science & Engineering
Co Authors: Ryan Fabbri
Federal storm damage reduction projects have been implemented along some of the most popular US beaches for decades. These projects are attractive to the local community for several reasons, including cost sharing and disaster recovery assistance. While beneficial to some communities, not all beaches are eligible for federal funding or federal funds may not be available for an approved project. The Town of Pawleys Island, SC received approval for a federally funded 50-year storm damage reduction project in 2004 totaling ~665,000 cy of sand over a 7,500 length of beach. However, as of 2014, federal funds were never appropriated for the project and the Town decided to move forward with planning a locally sponsored project to address significant erosion issues. The local project would place up to 1,000,000 cy of sand along an approximately three mile stretch of beach. The Town sponsored engineering studies and permitting for an offshore beach nourishment project, and received bids for the work in July 2018. During the week of the bid opening for the local project, the Town was informed that the USACE received supplemental funding following recent hurricane events, and that the Pawleys Island federal project was included in the funding. The Town had to quickly evaluate the potential benefits of the federal vs local projects to determine the most advantageous path forward, with incomplete information and much uncertainty. Considerations were given to the project schedule, noting that the federal project would be delayed at least one year from the local project, fill volume density, dune placement, alongshore fill limits due to only a portion of the eroded area being eligible for federal cost sharing, easements and legal concerns, and initial and maintenance project costs. The Town ultimately decided to move forward with the federal project, which is pending a scheduled start date of fall 2019, fifteen years following initial federal approval. We discuss the decision-making process, engineering requirements, and environmental protection measures from the perspective of the Town’s independent beach consultant. Lessons from this experience may be useful to other communities currently involved in ongoing or proposed federal storm damage projects, or those considering locally sponsored projects.
Presenter Bio: Steven Traynum is a project manager for Coastal Science & Engineering with 14 years of experience in beach nourishment and coastal processes. He specializes in beach restoration project design and permitting, environmental impact assessments, community outreach, and data analysis.
Human Impacts in Coastal Ecosystems in Puerto Rico (HICE-PR): A remote sensing, hydrologic, ecologic and socio-economic assessment with management implications
Maritza Barreto, University of Puerto Rico, Rio Piedras Campus, Graduate School of Planning
Co Authors: Juan Torres, Jorge Ortiz, Carlos Ramos-Scharron
An interdisciplinary study was conducted by integrating remote sensing, fieldwork and hydrological modeling techniques to infer how anthropogenic activities related to land cover/land use changes (LCLUC) have modified riverine inputs into the coastal and marine ecosystems (CMEs) in two watersheds in the north and south coasts of Puerto Rico. This study relies on a social ecological framework that makes explicit physical and social connections between watersheds and the coastal system. We present a summary of the evaluation of LCLUC, hydrological and CMEs (beaches and coral reef) located in both watersheds, the Rio Grande de Manatí and the Rio Loco watershed. The Soil and Water Assessment Tool (SWAT) was used to evaluate the possible effects of LCLUC on the water and sediment discharges from 1978-2016. Findings indicated important LCLUC showing a substantial shift from agricultural areas to forests and rangeland from 1970 to 2017. An increase in agriculture activities were subsequently identified from 2010 to 2016 in the lower part of both watersheds. According to the SWAT modelling data, an increase of both water discharge and suspended sediments were mostly related to periods of higher presence of agriculture and barren land types along the watersheds. Findings highlight the importance of vegetation cover in maintaining low soil erosion rates and suggest that unpaved access roads are the most dominant sources of sediment at the farm scale, therefore, watershed agricultural and developed infrastructure trends are particularly relevant. In addition, our findings suggest that sediment river discharge is one of the factors likely having a strong association with the quality and distribution of some CMEs in study sites. Decrease in coral cover and beach geomorphological changes were identified in sites near the river mouth, leading to CMEs deterioration and increased coastal vulnerability. Our group also identified public policy changes that continue to influence LCLUC and the distribution and quality of CMEs, given an ongoing controversy between agricultural and natural resource groups over land use designations in the area.
Presenter Bio: Geological Oceanographer and Professional Geologist. Professor of the Graduate School of Planning, University of Puerto Rico, Rio Piedras Campus. Dr Barreto is member of the following groups: ASBPA; Iberoamerican Beach Network (ProPlaya); Board of Geologist (Puerto Rico Government); Beach Board of Puerto Rico; National Blue Flag Commitee. Dr Barreto participate as a Principal and co investigator in research works supported by NASA, NOAA, USGS, NSF and UPRRP during the last 5 years.
Adam Finkle, Woods Hole Group
Mother Nature Erodes Best Laid Plans: Phased Retreat and Lessons Learned at Nauset Public Beach
Presenter Bio: In March of 2018, a series of nor’easter’s resulted in the dramatic loss of coastal beach and dune at Nauset Public Beach in Orleans, MA. Rates of shoreline change at Nauset Beach, which is located on a Town-owned parcel within the Cape Cod National Seashore, have been accelerating since the mid-1990’s. However, the erosion of 70 feet of dune over a 2-week span in March 2018 was unprecedented and resulted in the loss of an iconic beachfront dining destination, the forced relocation of an historic bandstand, and left remaining municipal buildings and infrastructure damaged and imminently threatened. Working with the Woods Hole Group, the Town filed an emergency permit application under the Massachusetts Department of Environmental Protection Severe Weather Emergency Declaration to raze damaged buildings and shore-up what remained of the coastal dune to improve the resilience of adjacent infrastructure and ensure the beach remained safe and accessible to residents, recreators, and seasonal visitors.
Fortunately, municipal officials had already begun planning for phased retreat from Nauset Beach by developing a series of design alternatives on a 30-year time horizon, and procuring adjacent, landward parcels to facilitate relocation of municipal buildings, parking, and infrastructure. Despite these planning efforts, the March 2018 storms greatly accelerated the proposed timeline for initial phases of the Phased Retreat Plan. During the summer and fall of 2018, Woods Hole Group worked closely with municipal partners, state regulatory agencies, and the National Park Service to augment existing design alternatives, select a preferred alternative, secure necessary permits, and develop a comprehensive bid package for Phase 2 of the Plan. Construction funds were mobilized following a fall Town meeting vote and construction began on Phase 2 of the Nauset Beach Phased Retreat Plan in December 2018. Phase 2 of the project involved the excavation and removal of 2 seaward rows of parking, relocation and/or removal of existing utilities, establishment of a new concession area, and the import of 27,000 tons of beach compatible sand for coastal dune enhancement along the landward edge of the existing degraded dune. Woods Hole Group provided the Town with construction support services and oversight throughout the implementation phase. The following presentation will focus on the steps taken by the Town to accelerate phased retreat from Nauset Beach and lessons learned following construction.
A New Generation Master Planning Effort Underway at Waikīkī Beach.
Dolan Eversole, University of Hawaii Sea Grant/ Waikiki Beach Special Improvement District
Co Authors: Rick Egged
This talk will describe some of the community-based current design efforts (not just engineering) to manage and improve Waikiki Beach.
The Waikīkī Beach Special Improvement District Association (WBSIDA) has developed a Beach Management Plan for Waikīkī in partnership with the University of Hawai‘i Sea Grant College Program (Hawaii Sea Grant). The primary goal of the Waikīkī Beach Management Plan is to improve the quality and sustainability of the public beach and nearshore resources along Waikīkī Beach. The Project is part of a broader environmental initiative, the Hoʻomau ‘O Waikīkī Kahakai which translates to (Waikīkī Beach renews itself). This initiative is being conducted as a Waikīkī Beach “Master Plan” and serves as a guiding principle for the community visioning process for Waikiki Beach and includes development of several inter-disciplinary project strategies.
The primary objective of the project is to create and support a stable and resilient beach in Waikīkī while improving beach conditions and shoreline infrastructure assets. The Project analysis and recommendations also consider the unique natural, historical, cultural, and economic value of Waikīkī. The primary outcome of the project is development of a Feasibility Study, Environmental Impact Statement (EIS), and project conceptual designs for beach improvements at Waikīkī for the Department of Land and Natural Resources (DLNR), Office of Conservation and Coastal Lands (OCCL). Specific project engineering designs and improvement plans will be developed over the project lifetime.
Stakeholder engagement and community outreach are critical components of the beach management plan. The outreach includes various efforts to identify stakeholder concerns, gather feedback on potential beach management strategies and alternatives, develop collaborative partnerships and agreements, and build stakeholder consensus. Interviews, focus group meetings, and workshops are being held with key stakeholders in the public sector, private sector, and the Waikīkī community to identify information needs, concerns, and support for various beach management strategies. A series of stakeholder and community design charrettes are being planned for Waikīkī in order to develop a vision and design rational process for future designs with consideration of sea-level rise projections in the alternative design analysis. These design charrettes involve critical thinking about the future conditions of Waikīkī beach, priorities for protection and integration of the beach improvements with the backshore development to be resilient and sustainable functional public areas.
The WBSIDA has developed a Waikīkī Beach community advisory committee to help inform project development, serving as a community representative to the project team. A series of advisory committee and public meetings has also provided opportunities to educate stakeholders and the general public with topics to include the history and evolution of Waikīkī Beach, coastal and beach processes in Waikīkī’s littoral cells, historical and modern approaches to beach management, and coastal hazards (including sea level rise).
Presenter Bio: Dolan Eversole currently serves as the Waikīkī Beach management coordinator through the University of Hawai‘i Sea Grant Program, in partnership with the Waikīkī Beach Special Improvement District Association. Dolan Eversole is a Coastal Geologist by training having earned his degrees in Geology from the University of Hawai‘i. Dolan served from 2003 to 2010 as a technical and policy advisor to the Hawaii Department of Land and Natural Resources (DLNR) on coastal management and hazard mitigation issues. Dolan draws from years of experience as an ocean recreation enthusiast and ocean lifeguard that has complimented his position as a coastal geomorphologist.
To Retreat or not to Retreat: Decision-Making by Residents of Coastal Communities
Ayse Karanci, Moffatt & Nichol
Increasing frequency and intensity of coastal flooding is affecting many sections of coastline around the world. Understanding the long-term dynamics of management and policy decisions is important for creating effective adaptation policies. The aim of this study is to investigate the ramifications of sea level rise adaptation actions in a coastal resort community.
Using a coastal community agent-based model this study establishes a bottom-up analytical framework that can represent interaction between human decisions and morphological conditions of the coast. The model simulates the effects of storms, SLR and soft coastal protection measures on the morphological landscape as well as social decisions based on community attractiveness. The management choices considered are “hold the line” with beach nourishment efforts, creating natural coastal habitat that provides protective functions through retreat, and a combined approach with a surge barrier for storm-driven floods and retreat for areas which experience nuisance floods.
The results of exploring the sea level rise management options indicates that policies that move people and buildings away from coastal hazards (e.g., managed retreat) are most successful in protecting property from flooding impacts. The study also examines the sensitivity of retreat decisions to buyout incentives and property tax rates, including betterment taxes for community adaptation projects.
Presenter Bio: Ayse Karanci is a Coastal Engineer with Moffatt & Nichol in their Raleigh office. She received her Ph.D. in civil/coastal engineering from North Carolina State University. Her research focuses on numerical coastal modeling; coastal management and mitigation; coupled-human nature systems; climate change and social dimensions.
Improving Efficiency of Coupled Hydrodynamic Predictions by implementing a Fetch-Based Parametric Wave Model
Samuel Boyd, Florida Institute of Technology – Dept. of Ocean Engineering and Marine Sciences
Co Authors: Robert Weaver
A fetch-limited parametric wave model is created for making hydrodynamic predictions in a restricted estuarine environment. Model development is motivated by the need to improve the efficiency in existing coupled hydrodynamic models which are computationally expensive. The improved efficiency will allow for improved ensemble wave-surge forecasting. The model is developed for use with the automated estuarine modeling system Multistage which makes use of a one-way nesting technique as opposed to the continuous single-domain approach. The performance of the parametric model is evaluated with respect to a third-generation wave model: Simulating Waves Nearshore (SWAN). 2D wave height contours are generated by SWAN and the parametric model over the same domain and compared for consistency. Once the model performance is established, the parametric model is coupled to the Advanced Circulation Model (ADCIRC) and results are compared to the ADCIRC-SWAN coupled model system. The coupled parametric model is run for 4 different sea states with wind forcing from each cardinal direction. Model performance is evaluated based not only on wave height differences but also run-time efficiencies. This project seeks to determine if a parametric wave model may be an efficient alternative for replacing the widely used third-generation wave models for faster run-times enabling ensemble simulations of storm impacts. The current version of the model may be employed in any semi-enclosed or restricted estuarine environment. Future work will involve extending the model domain into the open ocean for application in coastal regions as well.
Presenter Bio: I am a Masters student presenting my current progress in my thesis research. I am very interested in obtaining employment from a reputable firm or government agency in the field of ocean engineering/ modeling so I would love any opportunity to share my work and meet other professionals in this field. I believe that this work may be very valuable in real coastal applications and I would love to see what progress other people are making in the ocean community as well.
Multiscale simulation of erosion and breaching of barrier islands: Coupling XBeach and ADCIRC
Alireza Gharagozlou, NC State University
Co Authors: Casey Dietrich, Margery Overton
Barrier islands are susceptible to erosion, overwash, and breaching during intense storms which can enhance the flooding in the back-barrier areas. Large-scale coastal flooding models are very useful tools to predict the inundation of low-lying areas during a storm, however, such models typically lack the spatial resolution to capture the fine-scale beach morphological changes. In this study, we model the storm-driven island breaching and then we explore the requirements for bridging the gap between dune-scale morphodynamic and region-scale flooding models.
Hurricane Isabel made landfall in coastal North Carolina on Sep 18, 2003, as a Category 2 hurricane. The largest erosion event occurred near the western end of Hatteras Island, where the island was breached due to extensive erosion and overwash. The breach resulted in a 520m-wide inlet that connected the ocean and the sound. We use XBeach, an open-source tool for hydrodynamic and morphodynamic modeling, to simulate the breaching of the island during the storm. The initial DEM for the model is derived from pre-storm surveys, and the data for waves and water levels at the boundaries are extracted from a tightly-coupled, ADCIRC+SWAN simulation.
Model results are validated by comparisons with post-storm surveyed data. The modeled dune erosion, breaching, and channel depth matches the post-storm data well, proving the reliability of our model in predicting storm impacts on the domain. Then, the updated topography is applied in larger-domain model ADCIRC, thus allowing for enhanced flooding predictions in communities along Hatteras Island. It is found that even using a fixed topography in the region-scale model, the flooding predictions are improved significantly when predicted post-storm topography from XBeach is implemented. In this presentation, we will present the results from this loose coupling, which allows for waves and surge to push across the inlet, and thus improves the accuracy of storm forecasts.
Presenter Bio: Alireza Gharagozlou is a Ph.D. student at NC State University. His research interests mainly include coastal hydrodynamics, numerical modeling, and sediment transport. Alireza obtained his master degree at the University of Tehran, Iran. Currently, he is working on a project that involves modeling the erosion, overwash, and breaching of barrier islands during storms. The goal is to improve the flooding prediction by coupling the morphodynamic model to region-scale flooding models.
Impact of Storms on a Barrier Island Aquifer
Rachel Housego, MIT-WHOI
Co Authors: Britt Raubenheimer, Levi Gorrell, Steve Elgar
Flooding is a serious societal and economic concern on barrier islands owing to their low elevations. During storms, barrier island flooding results from both precipitation and high groundwater levels. Oceanic water fluctuations driven by waves, tides, and setup increase the elevation of the water table in the coastal aquifer. The resulting bulge of high groundwater propagates inland, attenuating with distance from the shore. The bulge may cause groundwater flooding up to several days after a storm has passed if the elevated groundwater exceeds the land surface. However, the propagation of the storm-driven fluctuations in the coastal water table are not understood.
The effects of storms on a coastal surface aquifer are investigated using groundwater heads and salinities measured every 10 min from Oct 2014 – 2018 at 8 locations spanning the 550-m-wide barrier island near Duck, NC, USA. Wave height and precipitation also were measured at the site by the U.S Army Corps of Engineers Field Research Facility. Offshore (26-m water depth) wave heights exceeded 4 m approximately 14 times owing to tropical storms (including Hurricanes Joaquin (2015), Hermine and Matthew (2016), Jose and Maria (2017), and Michael (2018)) and nor’easters. Shoreline water levels were elevated at least 0.65 m above normal tidal levels by storm surge (measured in 6-m depth) and wave-driven setup (estimated as 0.2 times the offshore wave height) during 27 storms. Infiltration from surge, tides, and waves caused up to 2 m increases in the groundwater level under the dune. These observations are used to validate a simple analytical model to predict the water table evolution across the barrier island from precipitation and the storm-driven fluctuation in the shoreline water level.
A citizen-science flood reporting phone application (app), iFlood, was developed to assess the ability of the analytical model to predict groundwater-driven flooding events spanning the Outer Banks. iFlood collects location data, photographs, and survey responses about flooding across the Outer Banks reported by app users. These data will help us assess whether the analytical model predicts the timing and location of groundwater-driven coastal flooding accurately. App functionality, development, and preliminary results from iFlood will be discussed. Funding provided by USCRP, NSF, and ASD(R&E). We thank the USACE CHL-Field Research Facility for ocean and meteorological observations, Heidi Wadman and Jesse McNinch for assistance deploying the groundwater wells, and Andy Garman (Nags Head town manager) and Chris Layton (Duck town manager) for assistance advertising and distributing the iFlood app.
Presenter Bio: Rachel Housego is a PhD candidate in the MIT-WHOI Joint Program and National Science Foundation Graduate Research Fellow. She is working with Dr. Britt Raubenheimer to study how changes in hydrodynamic and meteorological conditions impact coastal groundwater, using observational data and numerical modeling. Her goal is to better characterize feedbacks between ocean, groundwater, and shoreline processes to improve predictions of storm-driven hazards, such as flooding and erosion.
Parcel-Scale Mangrove Wave Attenuation: Physical Modelling and Field Measurements
Tori Tomiczek, US Naval Academy
Co Authors: Anna Wargula, Sabella Goodwin, Victoria Laveck, Marie Jendrysik
Today’s coastal communities are threatened by both chronic (e.g. nuisance flooding, erosion, sea level rise) and acute (e.g. hurricanes, Nor’Easters, tsunamis) hazards, emphasizing the need for residents and communities to make challenging decisions: retreat or implement successful, sustainable adaptation solutions to mitigate storm impacts to environmental, social, and physical systems. Natural and nature-based features (e.g. marshes, wetlands, mangroves) are promising adaptation alternatives that have been observed to not only provide ecological and social cobenefits, but also dissipate waves and reduce damage to nearshore structures during extreme events. However, the engineering performance of these natural systems remains uncertain, limiting their implementation in adaptive coastal design. This work quantifies the potential for mangroves shorelines to provide coastal protection by synthesizing physical model experiments of mangrove effects on hydrodynamic transformation and wave-induced loads on idealized inland structures and field measurements of boat wake transformation through mangrove islands near Key West, FL, USA.
Hydraulic experiments were conducted in Oregon State University’s Directional Wave Basin. We constructed 100 physical models of the mangrove trunk-prop root system at a 1:16 geometric scale. Random and transient (tsunami-like) wave conditions were generated with and without the presence of a background current for three experimental configurations with mangrove cross-shore thicknesses of 0, 0.51, and 1.19 m, respectively, representing full-scale cross-shore distances of 0, 8.2, and 19.0 m, respectively. Water surface elevations, velocities, and loads on idealized structures positioned 0.41 m behind the inland-most mangrove trunks were recorded for each wave condition and shielding configuration. Results indicate that transient wave forces were reduced by 21-65% for trials conducted when structures were shielded by a 1.19 m (19.0 m full-scale) mangrove fringe and suggest a dependency of force mitigation on the shielding mangrove cross-shore thickness and incident wave conditions (amplitude, period, current).
Field experiments conducted in Key West, FL measured boat wake transformation through mangrove islands. Pressure gauges were used to measure water surface elevations in front of, within, and behind a mangrove fringe adjacent to a heavily used boating channel; over 250 unique events were observed between 4-7 July, 2019. The 20 m cross-shore expanse of mangroves reduced the maximum water surface elevation by over 50% in some instances when comparing peak water surface elevations measured at the fringe of the mangroves to those recorded just behind the mangrove island. In addition, the temporal signal of the wake was affected due to mangrove interaction with propagating waves. Ongoing work will further quantify wave reduction in the presence of mangroves for other wave conditions, including large storm waves, to inform coastal stakeholders about natural and hybrid adaptation measures.
Presenter Bio: Tori Tomiczek is an Assistant Professor at the U.S. Naval Academy. She earned her B.S. at the University of Florida and PhD at the University of Notre Dame. She completed a post-doctoral fellowship at Oregon State University before joining the Ocean Engineering faculty at USNA in 2017. She has participated in field reconnaissance surveys evaluating damage and recovery and has enjoyed working on physical model experiments at USNA, OSU, and Kyoto University. She is interested in better understanding wave-induced forces on coastal structures to inform design guidance and finding sustainable, resilient solutions that mitigate damage due to coastal hazards.