4A — Modeling Super Storm Sandy Session 2 ● Monmouth 3

 

Effects of Sea Level Rise to Beach Erosion during Tropical Storm

Tianyi Liu

GZA, Inc./Coastal Engineer Specialist

tianyi.liu@gza.com

We modeled Hurricane Sandy using a circulation, wave and sediment transport modeling system ADCIRC+SWAN+XBeach in Atlantic Ocean and Connecticut Coast under current and future sea level conditions. The model uses a large scale mesh that covers Atlantic Ocean and Gulf of Mexico for the surge-wave model ADCIRC+SWAN, which computes storm surge and waves during Sandy and produces circulation/wave boundary conditions for the small scale and high resolution model XBeach at Stratford barrier beach on Connecticut coast. Sediment transport modeling by XBeach shows breach of barrier beach at Stratford coast and calculates the total volume loss of sediment during Sandy. Applying the USACE sea level rise condition of 0.87 feet by year-2065, the total volume loss of sediment at Stratford beach was calculated to increase by 29.6% during the tropical storm with same intensity as Hurricane Sandy. Coastal resiliency plans were developed for shoreline protection at Connecticut coast.

Tianyi Liu, PhD, is a Coastal Engineer from the Water Resource group of GZA Inc.. Tianyi Liu has extensive experience in coastal engineering specifically in coastally modeling. His modeling experience includes hydrodynamic, wave, storm surge, sediment transport modeling. He has worked on flood-risk evaluation projects and will provide engineering support regarding climate change and risk assessment.

 

Modeling historical storms and waves in the Mid-Atlantic and New York bights

Roham Bakhtyar

Stevens Institute of Technology

rbakhtya@stevens.edu

The US east coast is influenced by both extratropical and tropical cyclones, and therefore is vastly vulnerable to coastal floods and waves. In this study, the wave responses in the Mid-Atlantic and New York bights were investigated using a well-established and fast numerical framework. A surface wave model was coupled with three-dimensional ocean circulation model. For the ocean circulation module, we have used time-dependent version of the Stevens Institute Estuarine and Coastal Ocean hydrodynamic Model (sECOM), while the Mellor wave model was used for generating surface gravity waves. The model results were compared against the well-known and available observational data for historical storms, with good agreement found. The numerical results showed that the combined ocean-wave model is very accurate for wave height and moderately accurate for average wave period. Generally, the analysis shows that, with reasonable hypotheses, it is possible to simulate and predict the coastal zone waves under extreme storms. Then, we present the model-based assessment of the largest waves impacting the region during past century. The historical-modeling technique present here can be used for studying pre-historic hurricanes. Finally, we use a storm erosion index (SEI) as a means to quantify the damage and erosion potential of historical coastal storms.

Roham Bakhtyar is currently a researcher at Davidson laboratory of the Stevens Institute of Technology in Hoboken, NJ. I received my PhD and MSc degrees in coastal engineering and water resources research. Furthermore, I received my BSc in civil engineering. My main areas of research are ocean engineering, numerical modeling of nearshore processes, hydrodynamics, multi-phase flow, sediment transport, storm surges and sea level rise, fluid mechanics, coastal floods, and physical dynamics of coastal oceans.

 

Comparison of Three Overtopping Discharge Calculation Methods by Calculating Seawall Overtopping in Bay Head using SBEACH Output

Fanglin Zhang

Stevens Institute of Technology

fzhang9@stevens.edu

Bay Head, located along the northeastern coast of New Jersey, is protected by a 4,300 ft. long century-old relic seawall. Hurricane Sandy made landfall at New Jersey on Oct. 29, 2012, evolving into a 100-yr storm event in the Bay Head area. The buried seawall effectively defended against considerable wave and surge impact and proved its immeasurable value as being an efficient last line of defense against damage. Although the wall prevented catastrophic damage to structures behind it, damage due to waves overtopping the wall did occur.

Wave overtopping of structures is a significant parameter in the design and performance of a coastal structure. Average overtopping discharge and dimensionless overtopping discharge are two extensively used methods to determine the volume of water carried over the structure. Average overtopping discharge describes the overtopping condition by giving the total volume of water overtopped by a certain number of overtopping waves, while dimensionless overtopping discharge describes the proportion of waves overtopping. Empirical estimates of overtopping discharge have been developed from physical model tests (e.g., Owen, 1980, 1982; Ahrens and Heimbaugh, 1988b; Van der Meer and de Waal, 1992).

Existing cross-shore shoreline change models (e.g., SBEACH) are capable of simulating storm-induced beach erosion and the failure of bulkheads and seawalls due to wave and surge attack, but have not been developed to simulate wave overtopping of structures. The present research assesses the accuracy of using SBEACH output parameters and the relationships of Owen, Ahrens, and Van der Meer, for the prediction of overtopping discharge observed at Bay Head during Sandy.

Fanglin Zhang is a graduate student who majored in Ocean Engineering in Stevens Institute of Technology, department of Civil, Environmental and Ocean Engineering. She received her Bachelor’s degree in Naval Architecture and Ocean Engineering in 2014 in Jimei University, China. Her interests include coastal numerical models, coastal structures design and coastal hydrodynamics.

Co-authors: Thomas Herrington, Jon K. Miller

4B — Modeling Inlets & Shoreline Response ● Monmouth 4

 

Dynamics of a Small Tidal Inlet and the Search for Channel Stability

Bret Webb

University of South Alabama

bwebb@southalabama.edu

Little Lagoon is a long, narrow, shallow coastal lagoon behind the beautiful restored beaches of Gulf Shores, Alabama. The lagoon’s only permanent connection to the Gulf of Mexico is a narrow, stabilized inlet: Lagoon Pass. Management of the pass has been nearly continuous at times over the past few decades with tremendous effort expended on maintaining a court ordered minimum cross-sectional flow area of ninety-square-feet for the purpose of water quality. Having a somewhat divisive litigious history, with at times countervailing interests of down drift and lagoon property owners, any mention of modifying the pass or its maintenance has often been met with a healthy dose of skepticism. And yet the pass recently received a major modification with a doubling of the inlet throat width, replacement and extension of the jetties, and other associated upland improvements to an adjacent public park.

For the past few years the University of South Alabama has been monitoring the coastal processes in the vicinity of Lagoon Pass. The monitoring effort has included frequent bathymetric and shore surveys of beach profiles up to two miles on either side of the inlet, channel surveys, and surveys of the ebb and flood tidal shoals. Mapping of lagoon water quality has been conducted as well. In addition to the field data collection, a two-dimensional model of coupled hydrodynamics and sediment transport was developed to simulate tidal and wave processes, sediment transport, and morphology. The model was created using the U.S. Army Corps of Engineers’ Coastal Modeling System (CMS) and validated with measured bathymetry, tides, and waves in the study area. With some exceptions, the final model demonstrated adequate skill when predicting morphologic change over a six-week period in the fall of 2015.

The CMS model was run for a twelve-month period using predicted tides, measured waves, and observed winds in two configurations: one representing the pre-project inlet geometry and the other with the recent engineering improvements. Interestingly, the primary results were consistent with the coastal engineering consultant’s own modeling investigations using Delft3D: that the doubling of the throat width would increase the tidal velocity through the pass and, therefore, more effectively maintain the minimum flow cross-sectional area. However, both models were not totally correct for a reason that, these authors believe, has not yet been addressed in the published literature. The water levels of this coastal lagoon are strongly influenced by submarine groundwater discharge (SGD) from the underlying shallow aquifer. Over a range of realistic SGD rates supplied to the CMS model as freshwater inflow boundary conditions the subsequent tidal inlet morphology exhibits very different behavior. In some cases, simulation of the SGD is seen to promote deposition and shoaling within the pass and channel through modification of the lagoon water stage relative to that of the Gulf tide. This and other interesting results from the model simulations will be described in the presentation.

Bret Webb is an Associate Professor in the Department of Civil, Coastal, and Environmental Engineering at the University of South Alabama. Dr. Webb is also a registered Professional Engineer in the states of Alabama and Florida as well as a Diplomate of Coastal Engineering.

 

Inlet Management Study for Bunces Pass and Pass-A-Grille Inlet at the Mouth of Tampa Bay, West-central Florida

Ping Wang

University of South Florida/Professor

pwang@usf.edu

Bounces Pass and Pass-A-Grille inlets are located at the mouth of Tampa Bay. Both inlets contribute directly to the tidal exchange between Tampa Bay and the Gulf of Mexico and are parts of the complicated barrier-island and inlet system at the entrance. Pass-A-Grille inlet, bordered to the north by Long Key and to the south by Shell Key, is stabilized along the north side with seawall and riprap, while the south side of the inlet is not stabilized. The Pass-A-Grille ebb shoal has been used as borrow area for several beach nourishment projects. Bunces Pass, bordered to the north by Shell Key and to the south by Mullet Key, is completely natural with almost no engineering activities.

Both tidal inlets are tide dominated with rather stable inlet channel over at least the past 100 years. This is controlled by the large tidal prism through the two inlets. In contrast to the stable locations of the main tidal channels, the barrier islands in the vicinity of the inlets are very dynamic and illustrate rather unusual shapes. The entire barrier island of Shell Key in between the two inlets was developed over the past 50 years and adopts a U shape. The barrier island of Mullet Key, bordered to the south by the main entrance channel to Tampa Bay, demonstrates an L shape. Large shoreline variations on the order of several hundred meters over a decadal time scale are observed along the entire Shell Key and Mullet Key. This study sheds light on the detailed mechanisms of barrier-island formation.

Managing the extremely dynamic barrier islands in the vicinity of Bounces Pass and Pass-A-Grille is a challenging task. In addition to longshore sand transport, net cross-shore transport in the form of semi-periodic emerging of large swash-complex with subsequent onshore migration and shoreline attachment play a significant role in the sediment budget and morphodynamics of the inlet system. A numerical model of the two-inlet system is established to examine the change of flow patterns in response to the ebb shoal evolution. The goal of this study is to develop a sediment budget and a numerical model for the management of the two inlets and the adjacent barrier islands.

Ping Wang is the director of the Coastal Research Laboratory and a Professor at the School of Geosciences at the University of South Florida. Wang obtained his Ph.D. in Coastal Geology from the University of South Florida in 1995. Wang’s research interest includes: coastal sedimentary processes, nearshore sediment transport, nearshore wave and current dynamics, coastal morphodynamics, coastal engineering and management, numerical modeling of coastal environments.

 

Challenges on Hydrodynamic Modeling of Oregon Inlet, NC

Liliana Velasquez-Montoya

North Carolina State University

lvelasq@ncsu.edu

Oregon Inlet is located in the Outer Banks of North Carolina, south of the Town of Nags Head. It is the only inlet from Rudee Inlet, VA until Cape Hatteras, NC. Oregon Inlet is the northernmost inlet draining the water of the Albemarle, Currituck and Pamlico Sounds to the Atlantic Ocean in a multi-inlet system. The inlet was opened during a storm in 1846, the Herbert C. Bonner Bridge spanning the inlet was constructed in 1963 and a terminal groin was built on the southern shoreline of the inlet in 1991. The historically southward migration of the inlet is nowadays restricted by the terminal groin while the northern spit remains responsive to littoral drift processes growing towards the south and obstructing navigation in the authorized route. Oregon Inlet’s navigational channel is dredged by the U.S Army Corps of Engineers (USACE) to a depth of 14 feet, whereas the inlet’s main channel is located southwards and has reached a maximum constant depth of 40 feet.

With the aim to increase the understanding of the dynamics of this complex system that directly affects the tourism, fisheries, and commerce in the region, a medium-term (years) morphological model of Oregon Inlet is under development using the modeling suite Delft3D. This presentation details the initial phase of model development in which a two-dimensional hydrodynamic model including waves-currents interaction was calibrated and validated for Oregon Inlet. Challenges and proposed solutions on model development in a dynamic area with hydrodynamic data scarcity like Oregon Inlet will be discussed in detail. Time series of the closest tidal and wave gauges in the region at two different fortnight periods of early 2014 were qualitatively and statistically compared with simulated conditions. An overall good performance of the model was attained.

Curvilinear grids of variable resolutions were coupled together to optimize simulation times and model resolution within the inlet while still capturing the hydrodynamic conditions in its vicinity. The most updated bathymetric data near Oregon Inlet was gathered and later integrated into the Digital Elevation Model of coastal North Carolina developed for the North Carolina Floodplain Mapping Program. Water level boundary conditions are extracted at approximately 65-feet depth from simulations of the Northwestern Atlantic Basin using ADCIRC’s high-resolution mesh for North Carolina (NC9 mesh). Future phases of the morphological model set up will include generation of sediment size maps in the inlet and additional calibration of morphology-related physical and numerical parameters in the inlet area.

Liliana holds a M.S. in Earth Sciences and a B.S. in Civil Engineering from EAFIT University in Colombia. She is currently a PhD candidate in the Department of Civil, Construction, and Environmental Engineering at North Carolina State University. Her interests include coastal morphology, tidal inlet morphodynamics, modeling of coastal processes, multi-dimensional geospatial analysis and climate change.

 

Vulnerability to coastal flooding at two locations on Islesboro, Maine

Leila Pike and Nathan Dill

Ransom Consulting, Inc.

leila.pike@ransomenv.com

nathan.dill@ransomenv.com

Vulnerability to flooding due to storm surge and sea level rise is being studied on the island of Islesboro, Maine, using the model output data provided by the United States Army Corps’ of Engineers (USACE) North Atlantic Coast Comprehensive Study (NACCS). The vulnerability study is being performed in an effort to increase the resiliency of the island and help plan for climate change by examining two of the islands most critical locations: Grindle Point and the Narrows. Grindle Point is the home of the ferry terminal, which provides access to the mainland. The Narrows is a narrow section of the island that provides part of the town with the only over-road access to public services including the school, ferry terminal, fire department, and health center. Information on the vulnerability of coastal flood hazards for planning purposes is currently only available from regional numerical modeling studies, such as the NACCS and FEMA Flood Studies. In general these regional studies do not provide a sufficient level of detail to assess the flood hazard for individual critical locations, particularly in areas with highly complex coastal features like the Maine coast, or very specific locations, such as the ferry terminal of an island. When it is necessary to evaluate the hazard at specific locations, communities can benefit from additional local-scale analyses based on refined modeling driven by the regional model results. Here we present an example application utilizing the model output data from the NACCS to drive local-scale numerical modeling and analysis of the storm surge and wave hazard at Grindle Point and the Narrows on Islesboro. We describe the methods employed to downscale the NACCS information for these specific locations and present the results in terms of coastal flooding risk.

4C — Planning for and Managing Coastal Projects ● Monmouth 5

 

What We Know and What We Think We Know: Common Coastal Management Facts and Their Misconceptions Revealed

Christine Avenarius

East Carolina University

avenariusc@ecu.edu

In 2012 Superstorm Sandy caused property damage along the shoreline of many communities in New Jersey. Strong primary dunes helped to limit the amount of damage in some of these communities. However, the debate about the importance of dunes and beach management among coastal residents, town managers, and politicians is ongoing. Some coastal residents recognize that nature-based man-made dunes are still the most economically feasible and realistically adoptable long-term solution to coastal stabilization. Others consider the encroachment on their properties unacceptable or would like to see investment in hardened structures. Hence our team of researchers wanted to get a better understanding of the opinions and current knowledge about best practices in coastal management among local property owners. By learning who knows what about the purpose of dunes and other coastal management strategies we aim to make a contribution to dialogue among stakeholders that can pave the way for the adoption of suitable management practices and thus better protected shorelines in the future. We selected Ocean County, NJ as the site for our study because it features both coastal areas that experienced protection from dunes and coastal areas without strong dune fortification. Our two phase research design started with an exploratory phase that used a semi-structured interview instrument to collect perception data from a purposive sample of 60 local residents in six different municipalities along the shoreline. We followed data analysis of opinions about the purpose of dunes, beach replenishment, and the rights of oceanfront property owners with an explanatory phase that used a structured instrument with a quota sample of 300 Ocean County residents to verify the distribution of knowledge and opinions by demographic characteristics. This paper presents our insights about the current state of knowledge about dunes and beach restoration in Ocean County and suggests strategies for outreach and community engagement to strengthen future efforts in facilitating long-term coastal resiliency.

Christine Avenarius, PhD is an associate professor of sociocultural anthropology at East Carolina University. Her interest in understanding social and cultural change in reference to the interrelation between human cognition and social network structures has brought her from studies of immigrant integration processes in the US, China, and Namibia to the exploration of climate change and sea level rise perception among residents of North Carolina, Virginia, and New Jersey. As a graduate director she is particularly interested in engaging graduate students in the research process.

 

MUNICIPAL: A Planning and Training Tool to Improve the Recovery of Interdependent Civil and Social Infrastructures Following a Hurricane Event

Richard Little

Visiting Research Scholar Rensselaer Polytechnic Institute, Department of Industrial and Systems Engineering

littlr3@rpi.edu

It is well recognized that civil infrastructures (e.g., transportation, power, water supply and sewerage, and communications) are critical to the wellbeing of a community. However, critical commercial services such as food and drug distribution, banking, and motor fuel also play a crucial role in societal functioning. How well communities can withstand and recover from the damage and disruptions of extreme events is a key element in community resilience.

The Multi-Network Interdependent Critical Infrastructure Program for the Analysis of Lifelines (MUNICIPAL), developed by Rensselaer Polytechnic Institute (RPI), is a decision support tool for emergency managers and managers of these critical civil and social infrastructures (CCSI). MUNICIPAL provides users with a tool to view CCSI systems and their interdependencies; visually assess damage to these systems and the resultant service outages; and make preparedness, restoration, and recovery decisions. By enabling communities to recover more quickly and efficiently, overall resilience is increased.

Refined over several years and tested in a large coastal county in North Carolina, MUNICIPAL is a unique decision support tool that simulates the various moving parts of infrastructure in a coastal region to define optimal ‘rules of engagement’ before, during and after hazards. MUNICIPAL is designed to help answer questions like, Where are the healthcare facilities, supermarkets, drug stores, ATMs, and gas stations that serve the most people? Using readily available data, MUNICIPAL could quickly identify, for example, where the power grid needs to be repaired first to restore these vital services to the maximum number of people. This knowledge can be used to help emergency managers develop emergency response plans and training programs, as well as facilitate greater coordination between emergency management personnel and service providers when responding to interruptions in critical services.

Although computer-aided simulation and decision-support tools such as MUNICIPAL have a recognized role in disaster management, they are often underutilized by the practitioner community they are designed to serve. Recognizing this potential obstacle, the development of MUNICIPAL was guided by an interactive stakeholder involvement process to increase the likelihood that it would become a useful aid to planners and policy makers, emergency managers, and infrastructure service for training, awareness-raising, and team building among the diverse public and private stakeholders who are responsible for delivering, maintaining, and restoring CCIS.

The research team has completed data collection efforts for critical infrastructure, human services facilities, and commercial services in a large coastal county. On-going activities in this pilot community include geo-coding of additional data into a MUNICIPAL-compatible format, inclusion of U.S. Census Bureau and state population and socio-economic datasets, and assignment of HAZUS-MH fragility measures for typical commercial structures. Inclusion of this information will allow a more expansive assessment of interdependent service outages that take into account critical commercial services.

This presentation will explain the origin and development of MUNICIPAL, the stakeholder involvement process used to elicit user needs and secure feedback, and its potential value as a planning and training tool for coastal communities vulnerable to hurricanes, storm surge, and coastal flooding.

Richard G. Little is a Visiting Research Scholar in disaster mitigation at Rensselaer Polytechnic Institute. He was Director of the Keston Institute for Public Finance and Infrastructure Policy at the University of Southern California until 2012. Before joining USC, he was Director of the Board on Infrastructure and the Constructed Environment of the National Research Council (NRC) where he directed a program of studies dealing with hazard preparedness and mitigation and has lectured and published extensively on risk management and decision-making for critical infrastructure. He has over forty years experience in planning, management, and policy development relating to civil infrastructure.

 

Future Storm Surge Impacts in the Barnegat Bay

Thomas Herrington, Stevens Institute of Technology

A new, high-resolution, hydrodynamic model that encompasses the Barnegat Bay of New Jersey has been developed and validated for simulating inundation during Hurricane Sandy. A 100m resolution square model grid combined with a high-resolution LiDAR elevation dataset allow for the simulation of high-resolution overland inundation modeling. The back-barrier bay inundation model is a triply nested sECOM model application; sECOM is a successor model to the Princeton Ocean Model family of models. Robust flooding and drying of land in the model physics provides for the dynamic prediction of flood elevations and velocities across land features during inundation events. The inundation model was forced by water levels from the extensively validated NYHOPS hindcast of hurricane Sandy. Validation against 6 water level time series measured by USGS tide gauges located in the Barnegat Bay verified that the model is able to capture the spatial and temporal variation of water levels in the Bay observed during Hurricane Sandy. A comparison against 42 verified high water marks found that the model is capable of hincasting overland water elevation to within 0.2m (one standard deviation) at 71% of the total water marks measured. Model simulations forced with low (0.38m), middle (0.91m) and high (1.9m) projected sea level rise scenarios for 2100 show that the bay will respond similarly to that observed during Sandy for the low and middle sea level rise conditions. However, the increased water depth increases the propagation of the storm surge up the Bay, reducing the time of arrival of peak water elevations by 1 and 6 hours for the low and middle sea level elevations, respectively. For the high sea level rise projection, the Bay responds as if it were open to the ocean.

 

Life Cycle Cost Analysis of Beach Erosion Alternatives at Rincón, PR

Francisco J. Villafañe Rosa (1)

Co-authors: Luis D. Aponte Bermúdez, P.E., Ph.D.(2), and Miguel F. Canals-Silander, Ph.D.(3)

University of Puerto Rico at Mayagüez

• Graduate Student, Department of Civil Engineering and Surveying, francisco.villafane@upr.edu
• Associate Professor, Department of Civil Engineering and Surveying, luisd.aponte@upr.edu
• Associate Professor, Department of Engineering Science and Material, miguelf.canals@upr.edu

The town of Rincón located in the northwest corner of Puerto Rico as a current population of about 15,000. Like other US American beach community, Rincón’s local economy prosperity thrives on the condition of its beaches and has been driven primarily by the tourist industry since the late 1950s, its beachfront hotels, and the variety of small beaches along its shoreline. Coastal erosion and beach loss is a present threat of Rincon’s urban beach economic progress and has raised public and government concern to protect and preserved it. The study presented in this paper details a the recommended framework to establish a cost-benefit ratio of beach nourishment along Rincon’s shoreline vs. the cost of armoring the beach (beach loss) and land loss (managed retreat). Although beach nourishment is the primary method to combat beach erosion, a feasibility study is imperative to provide marine coastal zone manager the most reliable alternative. The study employs analysis and manipulation of geographical information system (GIS) utilizing data from the USGS, and the Center for Municipal Revenue Collection referred as CRIM by its acronym in Spanish. The USGS GIS data provides historical shoreline position and erosion rate estimates; this data is used to predict the expected shoreline inland projection. A correction to the projected inland shoreline is needed to take into account, sea level rise, terrain elevation, and existing beach armoring barriers (i.e. sea walls, metal sheet piling, and breakwater boulders). Field campaigns to gather GIS data of existing beach armoring system have been carried out; these systems are typically built on the oceanfront properties, after surge events, to protect the infrastructure. Beach armoring create a stability condition that prevents inland shoreline movement, but lessons learned from the past point out that man-made barriers have a high price to paid since these coastal barriers structures exacerbate beach erosion resulting in beach loss. The adjusted inland shoreline projection through the year 2050 and 2100 are related to the CRIM’s oceanfront property values using engineering economics to establish the benefit-cost ratio. Rincon’s CRIM database contains 10,097 parcels, of which 937 are oceanfront. The database provides a base property appraisal value adjusted to the year of 1958, of which 2,738 parcels (27%) contain data regarding recent sales value and transaction year. The mean growth rate of these properties represents a growth rate of 5.3%. Preliminary results of this study can serve to understand the value of beach nourishment as an effective alternative to secure Rincón’s beaches.

Francisco J. Villafañe-Rosa is from Hatillo, Puerto Rico. In May 2015, he earned a BS dual degrees in Civil Engineering and Surveying and Topography from the Department of Civil Engineering and Surveying of the University of Puerto Rico-Mayagüez (UPRM) Campus. Since January 2015, Francisco has been working as a research assistant on a project titled: Life Cost Analysis of Beach Restoration: Rincón, Testbed financed by the Puerto Rico Sea Grant Program at URPM. The PI’s of the project are Dr. Luis D Aponte-Bermúdez (PI), and Dr. Miguel F Canals-Silander (Co-PI).

4D — Regional Sediment Management Session 1 ● Atlantic 3

 

Historic RSM Coastal Navigation Sediment Placement in the U.S.

Nicole Elko

Elko Coastal Consulting, President

nelko@elkocoastal.com

The historic U.S. Army Corps of Engineers (USACE) project-by-project approach to navigation and beach and ecosystem restoration projects has employed the federal standard of maximizing net benefits for erosion control and storm protection projects while selecting the least-cost alternative for maintenance dredging of navigation channels. These independent approaches often do not capture the potential synergies and resulting cost savings and benefits from combination programs that make more efficient use of sediments, a concept known as Regional Sediment Management (RSM). This presentation describes a comprehensive assessment of the challenges and opportunities of national RSM implementation.

This research investigates and visualizes how USACE navigation sediment has been placed (disposed of) since 1998 by the coastal USACE Districts. The first phase of this project quantified navigation sediment that was dredged and placed using contract dredges. This phase has incorporated sediment dredged and placed by government-owned dredges. The total volume of sediment dredged and placed in coastal USACE districts since 1998 is over 3.4 trillion cubic yards (cy) of sediment. The New Orleans district has handled the most sediment at over 965 million (M) cy, an average of 56.8 Mcy per year.

An online, interactive tool that spatially conveys the dredging and placement activities of the USACE Navigation program at both the national and district level will be demonstrated to highlight potential RSM implementation opportunities.

Nicole Elko is Vice President of Science & Technology for the American Shore and Beach Preservation Association, Executive Director of the South Carolina Beach Advocates, and President of Elko Coastal Consulting in Charleston, SC. She received her Ph.D. from the University of South Florida in 2006 after working with the USGS Coastal Marine Geology Program, St. Petersburg, and while serving as the coastal coordinator for Pinellas County, FL. Dr. Elko has nearly 20 years of experience in the coastal field and has managed or assisted with more than 20 beach nourishment projects along the U.S. East and Gulf coasts.

The authors for this paper are:

Nicole Elko, Quin Robertson1, Linda Lillycrop2, Zhifei Dong1 and Heather Vollmer1.

1 – CB&I

2 – USACE ERDC-CHL

 

Regional Sediment Management (RSM) Dredge Optimization for USACE South Atlantic Division

Clay McCoy

USACE, Jacksonville District

Clay.A.Mccoy@usace.army.mil

The South Atlantic Division (SAD) RSM Optimization Pilot (OP) was developed to help define sustainable solutions across United States Army Corps of Engineers (USACE) missions and support RSM implementation strategies across project business lines. The goals of the OP were to: (1) develop and provide an actionable and optimized RSM strategy to most efficiently execute Navigation and Flood Risk Management program budgets, and (2) maximize the amount of dredging while also increasing the amount of RSM opportunities implemented. Funding saved and value created through RSM and optimization will allow USACE to execute a greater number of projects under flat-lined or reduced budgets. While RSM principles and strategies have been explored and implemented in many districts, this OP is the first comprehensive approach to define RSM opportunities for all projects and to quantify economic and environmental benefits at a regional scale.

SAD (coastal North Carolina through Mississippi) dredges approximately 60 million cubic yards of sediment per dredging cycle and the OP identified roughly $100 million in annual value associated with RSM implemented projects and opportunities. The presentation will highlight and summarize economically and environmentally optimized dredging and placement strategies throughout SAD. Value associated with the strategies is categorized by program (Navigation, Flood Risk Management, Combined Programs, Other-other federal agencies, state/local government) and dredged material type (beach quality sand, nearshore quality material, silt/mud/clay/rock). Value is primarily a function of quantified beneficial use and lower cost placement strategies relative to traditional upland or offshore placement. Examples of beneficial use includes placement of material on beaches or in nearshore environments that provides shore protection benefits and development of wetland habitat. Examples of lower cost placement strategies include thin layer placement in estuarine and shallow nearshore environments and open water placement in offshore environments.

Dr. Clay McCoy is a Project Manager for the USACE RSM Regional Center of Expertise in Jacksonville, Florida. Dr. McCoy has worked with at the Jacksonville District for five years focusing on coastal navigation and flood risk management projects. 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

Co-authors: Clay McCoy, PhD and Jacqueline J. Keiser, PG

 

Fire Island Inlet to Montauk Point, NY – Hurricane Sandy Interim Projects

Lynn Bocamazo

USACE, New York District

ynn.m.bocamazo@usace.army.mil

917-790-8396

Hurricane Sandy caused widespread coastal property and economic damage to the northeastern United States, and in particular the southern shores of Long Island, NY. Through the Congressional Hurricane Sandy Relief Bill (PL 113-2), the U.S. Army Corps of Engineers was given funding to develop interim coastal storm risk management projects in the area between Fire Island Inlet and Montauk Point. Two locations were determined to be in the federal interest for these interim projects, Fire Island Inlet to Moriches Inlet and Downtown Montauk. Hurricane Sandy Limited Reevaluation Reports were developed and approved, studying the coastal processes analyses and engineering design, the economic justification and environmental considerations for storm risk management features. The New York State Department of Environmental Conservation is the non-Federal sponsor for the projects, with additional partners including the Department of Interior (National Park Service, U.S. Fish and Wildlife Service, U.S. Geological Survey) and county and town governments.

The Fire Island Inlet to Moriches Inlet (FIMI) project spans portions of the barrier island over 25 miles (encompassing 17 communities within the Fire Island National Seashore), and includes the placement of over 8 million cubic yards of offshore borrow material to enhance dunes and berms, creation of approximately 65 acres of environmental habitat areas, over 100 public access pedestrian cross-overs, and multiple house relocations and removals. Construction of the project began in November 2014 and will be completed in early 2018, utilizing eight construction contracts.

The Downtown Montauk project will provide coastal storm risk management to over 3200 ft. of shoreline in the eastern Long Island hamlet of Montauk. The project consists of a reinforced dune created with approximately 11,000 geotextile bags, covered with three to six feet of native sand, a fronting beach berm, planting of dune grass, four pedestrian access cross-overs, vehicle cross-overs and two drainage structures. The project was initiated in October 2015 and competed in May 2016. The presentation will cover the design and construction of these challenging projects.

Ms. Bocamazo is the Chief of the Hurricane Sandy Relief Branch, in Engineering Division for the U.S. Army Engineer District, New York. Her principal coastal engineering work has been on coastal storm risk management and inlet navigation projects in New York and New Jersey. Ms. Bocamazo was the co-leader of the USACE National Coastal Working Group, which represents all coastal professionals within the Corps, from 2006 to 2013. Ms. Bocamazo was made a Diplomate of the Academy of Coastal, Ocean, Port, and Navigation Engineers in 2011. Ms. Bocamazo is a Registered Professional Engineer in New York State.

 

Nearshore Placement as a Regional Sediment Management Practice

Katherine E. Brutsche

USACE, ERDC

Katherine.E.Brutsche@erdc.dren.mil

Beneficial use of dredged material is an important practice for Regional Sediment Management in order to keep valuable sediment within the littoral zone and system. There are many ways to beneficially use dredged material, but an increasingly utilized method is to place sediment in the nearshore zone in the form of a berm or mound. The goals of this method are to place sediments as a feeder berm which supplies sediment to the beach profile and shoreline or place sediments as a stable berm to add protection to the shoreline through the dissipation of wave energy by breaking over the nearshore berm. However, little is known about the transport and dispersion of the sediment after it is placed in the nearshore. To that end, several research programs within the U.S. Army Corps of Engineers (USACE), Engineer Research and Development Center (ERDC), including the Regional Sediment Management (RSM) program, Coastal Inlets Research Program (CIRP), and the Dredging Operations and Environmental Research (DOER) program are working collaboratively to advance the science and our understanding of nearshore placement of sediment.

Several tools are available through the CIRP and RSM programs to determine whether sediment placed in the nearshore will move including the Sediment Mobility Tool (SMT; McFall and Brutsché, submitted), the Coastal Modeling System, and the Depth of Closure database. All three of these tools were used at a case study at Vilano Beach, Florida. Material was dredged by the USACE dredge Murden from St. Augustine Inlet and placed in the nearshore of Vilano Beach. Approximately 150,000 yd3 of material was placed in two discreet 1000 ft berms adjacent to a highly eroded section of the shoreline over a period of 45 days. Two different berm designs were chosen to determine whether berm shape had an impact on overall performance. Multi-beam and cross-shore surveys of the placement area were taken prior to construction and twice post construction. In addition to topographic surveys and the use of the SMT, two separate camera arrays were deployed to monitor qualitative changes in the shoreline and wave characteristics created by the presence of the nearshore berms. Finally, the Coastal Modeling System (CMS) was used for additional prediction, verification, and visualization of the berm’s influence on the hydrodynamic conditions.

Katherine Brutsché is a Research Physical Scientist at the USACE Engineer Research and Development Center in Vicksburg, M.S. She received her Ph.D. at the University of South Florida in 2014, where she also received her Masters of Science degree in Geology in 2011. Her Bachelor of Science degree in Geosciences, with dual emphasis in Geology and Earth Science Education, 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 as well as other issues pertaining to the dredging and placement of sediment in the nearshore.

4E — Beach Restoration: Project Performance ● Atlantic 4

 

Influences of Beach Nourishment on Shoreline Stability at New Jersey Beach Profile Network (NJBPN) Erosion Problem Areas

Kimberly McKenna

Stockton University Coastal Research Center/Director of Sponsored Programs

kimberly.mckenna@stockton.edu

Following the devastating impacts from Hurricane Sandy in October 2012, Congress passed Public Law 113-2 in January 2013 which provided the funding for the US Army Corps of Engineers (USACE) to restore authorized federal coastal storm damage reduction projects in New Jersey to their original design templates. Between 2013 and 2016, approximately 26,261,000 cubic yards of sand were used to rebuild the beaches and dunes along 92.7 miles of the 127 mile Atlantic Ocean shoreline (an average of 283,290 cubic yards per mile). A review of the changes to the New Jersey Beach Profile Network (NJBPN) locations indicates that this influx of sand benefitted former erosion problem areas. Erosion problem areas are defined from decadal trends in shoreline movement and dune/beach/nearshore volumetric changes where both volume losses and landward shoreline movements were recorded over a 25-year period (1986-2011). Erosion problem areas are plagued by the inability to rebound from storms due to several factors: not enough sand in the beach/dune/nearshore system, minimal cross-shore transport of sand from the nearshore to the beach, increased littoral transport rates, influence of tidal inlets, impact of large groins or armoring on sediment transport, human or natural influences on dune widths and elevations, and overwash. Of the 105 NJBPN locations, 16 are considered erosion problem areas and six of those were included in the emergency federal beach fills by 2015. Two in Monmouth County (Elberon, Deal) and one in southern Ocean County (Beach Haven) should receive sand by 2016 year end. Four erosion problem area sites are found within state or federally-managed locations and will not receive direct placement of sand (Island Beach State Park, Forsythe National Wildlife Refuge-Holgate Unit-, Green Acres Natural Area-Brigantine). Two sites are located in northern Ocean County (Mantoloking, Ortley Beach) and await resolution of real estate issues before the federal beach project can commence. One erosion problem area is located adjacent to a tidal inlet (North Wildwood) and is maintained by local interests using sand backpassing techniques to mitigate volume losses.

Kimberly McKenna is Director of Sponsored Programs at the Stockton University Coastal Research Center. She received her BS degree in geology from Stockton University and MS degree in geology from the University of South Florida. Kim is a licensed professional geologist in Delaware and Texas and has served on the Delaware State Board of Geologists.

 

Morphology and Shoreline Dynamics of a Southwest Florida Barrier Island: Natural and Anthropogenic Influences over the Last 75 Years

Tiffany Roberts Briggs

Florida Atlantic University

briggst@fau.edu

Big Hickory Island is a barrier island located along the mixed-energy southwest Florida Gulf Coast. This barrier island experiences high long-term rates of shoreline recession, with much of the erosion concentrated along the central and southern portions of the island. In an effort to mitigate the ongoing coastal erosion, a beach and dune restoration project occurred in 2013, utilizing sediment from an adjacent tidal inlet. In addition, seven concrete king-pile groins with adjustable panels were constructed subsequent to the completion of the beach nourishment. Near-term (decadal) and short-term (sub-annual to annual) natural and anthropogenic influences on the dynamics of Big Hickory Island are discussed through analysis of shoreline and morphologic change using historic aerial photographs and topographic and bathymetric surveys. Although much of the long-term anomalously high rates of erosion for the area are related to natural interchanges between the sand resources along the barrier island chain and adjacent ebb tidal deltas, additional reduction in sand supply is the result of human-interventions updrift of Big Hickory over the last several decades. The study concludes that coupled natural and anthropogenic influences are driving the coast towards a different morphodynamic state than would have occurred under natural processes alone.

Assistant Professor in the Department of Geosciences at Florida Atlantic University (FAU), specializing in coastal geology and geomorphology, with research publications related primarily to the morphodynamics of coastal change associated with storms, nourishment, and wave runup. She received a Ph.D. and M.S. in Geology from the University of South Florida (Tampa) and a B.S. in Environmental Science from the Honors College at the University of South Florida (St. Petersburg). Before beginning her current position at FAU, she taught geology at Louisiana State University in the Department of Geology & Geophysics. Briggs also co-chairs ASBPA’s Student & New Professional Committee and Science & Technology Committee.

Co-authors: Tiffany Roberts Briggs, Ph.D. and Nicole Elko, Ph.D.

 

Beach Restoration to Protect NC Highway 12 at Buxton, Dare County, North Carolina

Timothy Kana

Coastal Science & Engineering/President

tkana@coastalscience.com

Dare County (North Carolina) encompasses ~89 miles of ocean shoreline from the Town of Duck to Hatteras Inlet. In total, 50 percent of Dare County’s ocean shoreline is developed with 50 percent undeveloped and held in permanent trust by the Cape Hatteras National Seashore. NC Highway 12 is the main artery for access and emergency vehicles to the communities of Buxton and Hatteras Village, as well as National Park facilities. The narrow isthmus immediately north of Buxton Village has breached in the past and remains highly vulnerable to future breaches.

Coastal Science & Engineering (CSE) was retained by Dare County in 2012 and completed a feasibility study in 2013 for beach restoration in the Buxton area to protect NC Highway 12 north of the old Cape Hatteras Lighthouse site. Permit application and final design were initiated in August 2014, and NEPA/SEPA coordination entailed over a year of weekly meetings with National Park Service (NPS). The Environmental Assessment and seven other supporting documents (including littoral processes, biological assessment, essential fish habitat assessment, geotechnical data, cultural resources, biological monitoring, and monitoring and mitigation measures) were prepared by CSE and reviewed by NPS and other resource agencies prior to submission of permit applications to the USACE, North Carolina Division of Coastal Management (NCDCM), and NPS. After officially submitting permit applications in September 2015, all permits for the Buxton nourishment project were received by mid March 2016. The permitted project encompasses up to 15,500 linear feet (2.94 miles) of ocean beach and calls for up to 2.6 million cubic yards of beach-quality sand to be pumped onto the beach via dredge. The source of sand for beach nourishment will come from an offshore borrow area situated within state waters about 1.7 miles off the south section of the project. The borrow area is close enough to the project to be pumped via traditional suction cutterhead dredges as well as hopper dredges, yet in water depths that are well beyond the zone of active sediment exchange with the beach.

Funding for the project is from various local sources with no federal funding involved. Bids for the project were received on 7 April 2016, and the apparent low bidder was Weeks Marine, Inc. (Weeks). Dare County executed a contract with Weeks on 3 May 2016 for a total contract value of $22,150,000 to complete the maximum permitted 2.6 million cubic yards of work. Construction will be conducted in summer 2017 and is expected to be completed by 15 December 2017.

Dr. Tim Kana is founder and president of Coastal Science & Engineering based in Columbia (SC). He has 30 years experience in coastal erosion projects and has written over 250 reports and publications relating to causes of erosion, coastal and inlet processes, sediment budgets, beach nourishment, impacts of sea-level rise, and coastal zone management. CSE has developed plans and supervised construction of more than 35 beach nourishment and inlet relocation projects in South Carolina, North Carolina and New York. Dr Kana received the Morrough P O’Brien Award in 2015 from the American Shore & Beach Preservation Association (ASBPA).

 

St. Lucie County – South County Beach Project Plan Formulation

Michael Walther

Coastal Tech – G.E.C., Inc.; Vice President

mwalther@coastaltechcorp.com

The St. Lucie County South Beach Restoration Project encompasses approximately 3.3 miles of Atlantic Ocean shoreline immediately north of the Martin County line. The Project Area includes shoreline segments designated as critically eroded by the Florida Department of Environmental Protection – where upland development is threatened by erosion and recession of the beach-dune system. In September 2004, St. Lucie County suffered the impact of Hurricane Frances and Hurricane Jeanne within a period of 21 days; high waves and storm surge from the storms inflicted substantial damage on the shoreline, upland property, and infrastructure. The following year Hurricane Wilma came across the state from the Gulf of Mexico and passed offshore of St. Lucie County leading to more erosion. Towards the end of October 2012, just after the pre-construction survey was performed, Hurricane Sandy’s high waves and storm surge substantially eroded the beach and dune in the Project Area. The area is frequently affected by wintertime nor’easters which bring high waves and heavy erosion.

In November 2002, the U.S. Army Corps of Engineers (USACE) completed a Section 905(b) analysis for a St. Lucie County, Florida – Hurricane and Storm Damage Reduction Study for the South St. Lucie County Beaches. Because a Federal project is not expected to be undertaken for several years, St. Lucie County initiated the Project as an initial non-federal project to address the deteriorated shoreline and emergency conditions as soon as possible with parallel development of a Federal Shore Protection Project to provide for future re-nourishment of the beaches within the Study Area. The initial non-federal Project was constructed from mid-March to mid-May of 2013 to generally offset historical erosion, restore recreational beach, provide storm protection to upland properties, and restore coastal habitat.

In the spring of 2016, the USACE released its Draft St. Lucie County, Florida Coastal Storm Risk Management Feasibility Study and Integrated Environmental Assessment. In general, the USACE results are consistent with the design of the County’s non-federal Project and the following key elements:

• The 2013 non-federal project – placed about 682,500 cy of sand – with the expected re-nourishment interval at 10 years and a re-nourishment volume of 200,000 cy.
• The NED Project – is the 20ft Berm Alternative and is based upon the 2008 profiles (prior to 2012 Hurricane Sandy impacts) as the existing condition and is expected to entail an initial fill on the order of 530,400 cy with a re-nourishment interval of 18 years and a corresponding average re-nourishment volume of 380,000 cy.

This presentation will (a) review the formulation of the 2013 non-federal project and the currently proposed federal Storm-Damage Reduction project, and (b) compare the methods and resulting recommended plan for both projects.

In December 1977 Michael earned a Master of Science in Engineering from the University of Texas; his thesis entailed a Methodology for the Stream Function Solution to Wave Kinematics. As a former Air Force brat, Michael returned to Florida and worked with one of Florida’s coastal engineering firms. In 1984, Michael founded Coastal Tech and served as President of the firm until 2014. In December, 2014, Coastal Tech was acquired by GEC – based in Louisiana. Currently, as Vice President of Coastal Tech-G.E.C., Inc. (GEC) Michael oversees the firm’s coastal engineering services in Florida and supports GEC national coastal engineering practice.

4F —Building Ecological Solutions to New Jersey Coastal Community Hazards ● Atlantic 5

 

Building Ecological Solutions to Coastal Community Hazards in Post-Sandy New Jersey

Stacy Small-Lorenz

National Wildlife Federation, Climate Adaptation and Resilience Specialist

smalls@nwf.org

New Jersey’s 127-mile long coastline along the Atlantic Ocean and 83 miles of shoreline along the Raritan and Delaware Bays provide an unsurpassed combination of ecological riches. Combined with its 239 coastal municipalities, coastal ecosystems contribute to a tourism industry estimated to be worth over $16 billion annually, with beaches being a significant economic driver for this sector.

Furthermore, over 1.5 million migratory shorebirds call New Jersey’s pristine wildlife refuges and tidal wetlands home for some part of the year. While the bays, rivers, estuaries and oceanic habitats not only contribute ecological value, they also support a commercial fishing industry that harvests over 50 different species of finfish and shellfish annually.

The inherent value of these natural systems and vulnerability of human communities became apparent with Hurricane Sandy and subsequent coastal storms, as beaches, habitats and properties have been severely damaged or destroyed. With sea level rise and increased storms projected for New Jersey, the vulnerability of the remaining resources are at a greater risk. Though destructive, Sandy was the call to arms for a proactive and organized approach to protecting New Jersey’s coastal resources, with growing emphasis on the protective value of natural and nature-based features.

In 2015, the NJ DEP Office of Coastal and Land Use Planning launched an initiative to assist communities in protecting their coastal resources with a grant from the National Fish & Wildlife Foundation-Hurricane Sandy Coastal Resiliency Program. The project, Building Ecological Solutions to Coastal Community Hazards, includes academic, non-profit, public agencies and local governments. Partners are developing tools and voluntary incentives to help communities protect themselves and their coastal resources from natural hazards under the threat of intensifying climate impacts. This multi-disciplinary team includes coastal engineers, planners, ecologists, and educators, alongside municipal decision-makers.

Our proposed interactive panel discussion would highlight various aspects of this effort, including:

• Ongoing stakeholder engagement, including municipal vulnerability assessments to project future flood hazards to physical, social and natural assets.
• The development of natural and nature-based hazard mitigation best practices for NJ coastal communities that provide risk reduction and habitat benefits, using a web-based platform to allow easy public access.
• Case studies of pilot municipal projects, including highlights from planning efforts that propose beach and dune restoration or identify synergies among beaches, dunes, and other coastal/barrier island ecosystems. These will include highlights from our direct municipal technical assistance efforts and joint permitting guidance from state and federal agencies.
• Developing voluntary incentives through sustainability certification programs that encourage municipalities to seek out and implement ecological solutions to coastal hazards.
• Metrics and monitoring in development for assessing baseline conditions and evaluating ecological solutions to coastal community hazards.

 

Our interactive session will showcase the benefits of interdisciplinary collaboration in post-Sandy New Jersey. The following technical partners will be represented:

— NJ Department of Environmental Protection, Office of Coastal and Land Use Planning and the Land Use Regulation Program

— National Wildlife Federation

— Sustainability Institute, The College of NJ

— Stevens Institute of Technology

— Partnership for the Delaware Estuary

Session Organizer: Dr. Stacy Small-Lorenz is a Climate Adaptation and Resilience Specialist at National Wildlife Federation. As a member of NWF’s national climate safeguards team, Dr. Small-Lorenz advances climate-smart conservation and the use of ecological approaches for protecting people and wildlife from the impacts of climate change and other natural hazards. An avian ecologist by training, she holds a doctorate in avian ecology and has worked for the last 20 years in the field of habitat conservation, including research & monitoring, ecological restoration design & management, and conservation policy.

5A — Storm Surge & Flood Modeling ● Monmouth 3

 

Modeling the impact of historical storms on the Rhode Island shoreline

Lauren Schambach

University of Rhode Island/Master’s Student

lschambach@my.uri.edu

Co-authors: Lauren Schambach (1), Annette Grilli (1), M Reza Hashemi (1,2), John King (2), and Stephan Grilli (1,2)

(1) Ocean Engineering, University of Rhode Island, Narragansett, RI

(2) Graduate School of Oceanography, University of Rhode Island, Narragansett, RI

The impact of selected historical storms on the southern Rhode Island shoreline is modeled using a combination of hydrodynamic, wave, and erosion models. Results are compared with observations and the accuracy of the wave/erosion models is discussed at the event time scale.

Waves at the local scale are modeled using both the phase-averaged 2-D wave model STWAVE (STeady state spectral WAVE model) and the 2-D fully nonlinear and dispersive phase-resolving wave model FUNWAVE-TVD (Shi et al., 2012), on a very fine resolution grid (10 to 5 m) in the southern Rhode Island coastal area. The two wave models are forced by offshore boundary conditions based on either wave spectra defined at a local Wave Information Studies (WIS) node, or based on the output of simulations with the surge model ADCIRC coupled with the wave model SWAN, both run on a coarser unstructured mesh (10 km to 50 m).

While the spectral model provides an averaged view of the inundation, the phase resolving model simulates wave propagation in the time domain offshore of the Rhode Island coastline up to the inundation zone. Results of both models are compared and discussed, providing insight into the epistemic uncertainty. The use of FUNWAVE provides a method to identify the swash zone and the runup area. Additionally, as FUNWAVE also simulates the flow velocities in the time domain, its results can be used to map the wave-induced impulse forces and identify areas where the coastline is more sensitive to erosion.

Results of the wave models are validated using time series of surface elevation measured at local buoys during Hurricane Irene (August 2011). Coastal erosion is then simulated for selected storms using the erosion model XBeach (Roelvink et al., 2012). XBeach is nested inside the ADCIRC-SWAN model for boundary forcing. XBeach is a 2-D process-based phase-averaged model based on a convection-diffusion equation with pick-up and deposition functions. Results are then compared with the data measured along local cross-shore transects, before and after the storms.

Conclusions are provided regarding the accuracy of the wave/erosion models, and sources of uncertainty are discussed at the event time scale.

References

Roelvink, D., Reniers, A. J. H. M., Van Dongeren, A., Van Thiel de Vries, J., Lescinski, J., & McCall, R. (2010). Xbeach model description and manual. Unesco-IHE Institute for Water Education, Deltares and Delft University of Technology. Report June, 21, 2010.

Shi, F., J.T. Kirby, J.C. Harris, J.D. Geiman and S.T. Grilli (2012). A High-Order Adaptive Time-Stepping TVD Solver for Boussinesq Modeling of Breaking Waves and Coastal Inundation. Ocean Modeling, 43-44, 36-51, doi:10.1016/j.ocemod.2011.12.004.

Lauren Schambach is an Ocean Engineering master’s student at the University of Rhode Island. Her research focuses on modeling extreme storm events on the southern Rhode Island coastline.

 

Inundation Modeling for National Parks in the Northeast US using ADCIRC

Tayebeh S. Tajalli Bakhsh

Ocean Eng. PhD

Tayebeh.TajalliBakhsh@rpsgroup.com

The National Park Service manages several iconic cultural and natural resources along the Northeast coast, including the Statute of Liberty and Ellis Island in New York Harbor, and numerous sites within Gateway National Recreation Area (GATE), Fire Island National Seashore (FIIS), and Assateague Island National Seashore (ASIS). Because many of these locations experienced flooding and damages associated with the landfall of Superstorm Sandy, the NPS has partnered with the University of Rhode Island, and RPS ASA on an initiative to assess the vulnerability of these properties to future storm impacts. The approach has focused on developing both high accuracy elevation data and inundation models to evaluate storm surges under current and future conditions. The goal of this effort is to develop a robust data infrastructure and technical procedures that will be used in preparing for and responding to future storms at these properties.

To identify the most vulnerable park areas, a number of simultaneous data collection and mapping efforts have occurred, including: acquisition of high resolution LiDAR data on a regular basis, especially for the barrier island locations; high-accuracy GPS surveys of a cultural resource areas, historic buildings and other key park infrastructure; and continuous tide and water level measurements. These datasets are used to evaluate potential inundation using the ADvanced CIRCulation (ADCIRC) computer model – a finite element, nonlinear hydrodynamic model that is run on a highly resolved, unstructured mesh. For this study, two computational grids were developed, one covering both FIIS and GATE, and a second domain for ASIS. Each grid was refined in order to capture detailed coastal features such as inlets, marshes, and nearshore bars; each was updated with the best available elevation data including post-Sandy LiDAR and ground survey points.

Simulations of storm-induced flooding were performed for each park to predict inundation associated with a 100-year return period event, under various sea level rise scenarios. The modeling leveraged recent work conducted by the US Army Corps of Engineers (USACE) for the North Atlantic Coast Comprehensive Study (NACCS) for the boundary condition and forcing parameters. Water surface elevation time series from the NACCS save points were used to force the open boundary of the model, and the storm parameters from the NACCS database were used to define the storm track and wind and pressure fields using the Holland B method of parameterization. The hydrodynamic model output is being used to develop inundation maps, enabling park staff and managers to identify locations at risk, and prioritize resources during pre-storm planning.

Dr. Tayebeh S. Tajalli Bakhsh is a recent graduate of the University of Rhode Island, and is working as an ocean engineer and tsunami scientist with the RPS ASA. She has a broad experience in numerical modeling of tsunamis and coastal hazards, surface wave simulations and near shore wave processes. Combining her scientific knowledge in Physics and Oceanography, and her engineering background in modeling, she is a storm surge and hydrodynamic modeler for forecasting/hindcasting systems at RPS ASA. Prior to joining RPS ASA and as a research assistant at the University of Rhode Island, she simulated tsunami hazards along the US East Coast as part of National Tsunami Hazard Mitigating Program (NTHMP), and also some other critical projects around the globe (including NSF funded project on Indian Ocean Tsunami hazard, East Coast of Mozambique, Japan 2011 Tohoku event, Papua New Guinea Landslide generated tsunami, RPS ASA projects on tsunami hazard on some of the US East Coast Nuclear Power Stations), by improving and applying state of the art numerical models for simulating tsunami hazard.

 

Post-Fukushima Flooding Analysis for the Salem and Hope Creek Nuclear Generating Stations in South New Jersey

Michael Salisbury

Atkins North America, Inc.

Michael.Salisbury@atkinsglobal.com

Subsequent to the Fukushima disaster in Japan, the Nuclear Regulatory Commission (NRC) began a risk/safety review of all U.S. nuclear power plants. These efforts, in part, involve using state-of-the-art modeling and analysis to assess design flood levels and potential flooding sources at each plant. For nuclear power plants located in coastal environments, as is the case for the PSEG Salem and Hope Creek Nuclear Generating Stations, this is largely dictated by hurricanes and their associated storm surge.

Given the infrequent occurrence of hurricane activity along the New Jersey coast and the variability in characteristics (magnitude, frequency, track, etc.) amongst those hurricanes, there is no simple way to define an appropriate design-basis hurricane event for the PSEG site. As such, a probabilistic method (Joint Probability Method – Optimal Sampling; JPM-OS) was used to identify a range of potential hurricane parameter values that could produce significant storm surge at the site (NRC regulations call for the million-year return period flood level). In total, almost 100 synthetic hurricane events were included in the JPM-OS analysis. Each of these events are hypothetical, but have a defined level of probability of occurrence based on a statistical analysis of the historical hurricane data.

To support the JPM-OS analysis, a large-scale storm surge and wave model (ADCIRC+SWAN) was developed that includes the deep ocean, Delaware Bay/River, and coastal floodplain in one contiguous model domain. By using such a large-scale model, the natural growth and propagation of storm surge and waves is well represented in the model leading to accurate results at the project site. Ultimately, this model was used to simulate the storm surge and waves associated with each of the synthetic hurricane events identified with the JPM-OS process. Correlating the probability of occurrence for each of these events to their resulting storm surge yields an estimation of flood levels for various return period intervals.

 

As with anything NRC related, safety is of the utmost concern when establishing design and operational criteria for a nuclear power plant. According to the Saffir-Simpson hurricane scale, the hurricane events considered in this analysis ranged from strong Category 4 to Category 5 events. In comparison, Hurricane Sandy (the strongest storm event to impact the New Jersey coast in recorded history) transitioned from a weak Category 1 storm to an extratropical system at landfall. Specific to the PSEG site, this comparison highlights the level of conservatism built into the flooding analysis.

Mike is currently a Senior Engineer for Atkins North America, Inc. and has served as a project manager and lead engineer for a number of coastal modeling related projects throughout the U.S. and abroad. He has over 12 years of experience working on coastal related projects, including expertise in developing storm surge models for risk assessment, floodplain mapping, and long-term climatogy studies. He has published several peer-reviewed articles detailing the development and validation of various numerical models, and is Chair of the Coastal and Estuarine Hydroscience Committee for the Coasts, Oceans, Ports, and Rivers Institute of the American Society of Civil Engineers.

 

Mitigating Flood Risk and the Impacts of Climate Change at the World Trade Center

Mark Osler

Michael Baker Jr., Inc.

MOsler@mbakerintl.com

On behalf of the New York/New Jersey Port Authority, Michael Baker International has prepared a Water Intrusion Protection Plan for the World Trade Center complex in response to the major flooding experienced during Hurricane Sandy in 2012. This presentation will provide an update on Michael Baker’s work on this project since it was last presented at the 2014 ASBPA conference in Virginia Beach.

The centerpiece of recent efforts is a completed modeling regimen which encompasses shelf-scale hurricane surge modeling, nearfield urban flood routing, and a first-of-its-kind analysis of flooding within the interior and subsurface of the building infrastructure on site. This work yields an understanding of site-wide and project specific vulnerabilities, leading to realistic approaches to hazard mitigation. A detailed comprehensive 2-dimensional surface model was developed and linked to the multi-level subsurface infrastructure. This groundbreaking analysis included all main connections between the surface and within the subsurface infrastructure, such as floodwater flowing from the street, into a building lobby and down into the subsurface via stairways and elevator shafts.

Michael Baker, with Forum8 and XP Software, prepared a 3D animation to graphically demonstrate the extensive flooding of streets, subways, and subsurface infrastructure that occurred around the World Trade Center during the Hurricane Sandy storm event. The modeling was based on ADCIRC Model with 100m x 100m cells coupled with an XPSWMM Model using detailed 5’ x 5’ cells within the site itself. An XPSWMM 1-Dimensional hydraulic model was prepared to analyze flooding through the subsurface. Multiple scenarios were developed to understand where to create emergency access routes, and possible flood-proof doors. The subsurface model utilizes doorways, stairwells, elevator shafts, and air vents as openings for water to flow into the underground substructure. The final model results for both the surface 2-D and the subsurface 1-D were prepared in a 3-D animation to allow the decision makers to understand the flow characteristics and movements through the infrastructure. This presentation will provide information on emerging best practices and state of the art technology tools and techniques used to evaluation of flood hazard risks and solutions to address extreme weather resilience in the transportation sector, including planning and programming, capital improvements, and operations and maintenance.

Mr. Osler serves as an Associate Vice President for Michael Baker International where he leads the firm’s national Coastal Science and Engineering practice. His 15 years of professional experience have centered around the computer modeling of coastal hydrodynamics with a focus on the impacts of climate change, coastal flood hazard analysis and probabilistic risk assessment. He has worked with clients throughout the Atlantic, Gulf, Pacific and Great Lakes coasts, as well as in Alaska and Antarctica. Osler holds a Bachelor’s Degree from Lehigh University and a Master’s degree from the University of Delaware’s Center for Applied Coastal Research.

5B — Modeling Coastal Processes & Human Response ● Monmouth 4

 

GeoCoastal: CSHORE Modeling Tools for accessing shoreline response to Coastal Hazards

Jeff Gangai

Dewberry/Senior Associate

jgangai@dewberry.com

Dewberry’s GeoCoastal: CSHORE, an Automated Cross-shore Modeling and Analysis System is a robust suite of engineering functionalities for coastal hazard studies. The coastal flood modeling process requires multiple, highly-specialized computer programs and the processing of large amounts of data. Integrated on top of a GIS-based platform, GeoCoastal: CSHORE used the USACE CSHORE model to conduct cross-shore coastal modeling and analysis with enhanced functionality and processing. Originated from coastal hazard studies in the Great Lake region of the United States, GeoCoastal CSHORE conducts fully automated modeling and statistical analysis of coastal erosion, wave propagation through the near-shore, and wave run-up by integrating 8 major separate steps. This integration was achieved by using the ArcGIS platform, which provides robust and advanced geospatial capabilities.

This presentation will show how GeoCoastal CSHORE can be used to evaluate coastal hazards and free users from manually preparing and baby-sitting inputs and outputs. The modeling process essentially becomes of a click-of-a-button process, which greatly increases efficiency, prevents human errors in the complex workflow, and provides timely visualization for the users to make engineering judgment along the way. Because of its ease of use, engineers can run different scenarios in order to generate the best results; the tedious and laborious nature of the previous workflows discourages users from running and revising models. The application also allows the engineers to customize the workflow in batch or step-wise mode, and to keep track of all the parameters used at various stages of the modeling by storing them in databases and output files.

Examples of the use of GeoCoastal CSHORE in Great Lakes coastal studies for Lake Erie and Lake Ontario will be shown. In these studies hundreds of coastal transects had to be modeled each with hundreds of storms with the CSHORE model to make a history of responses at each transect that could be statistically analyzed. GeoCoastal CSHORE allowed for an efficient process that allowed users to make multiple runs, each time fine tuning inputs. The results to the modeling allowed for the incorporation of more accurately modeled near shore processes into the identification and mapping of coastal risks and hazards.

Mr. Jeff Gangai has been practicing coastal engineering for over 20 years. He holds a Bachelor of Science in Maritime Systems Engineering from Texas A&M University at Galveston and a certificate in Coastal Engineering from Old Dominion University. Before joining Dewberry he worked for five years with the USACE at the Galveston, TX District. For over 16 years he has worked at Dewberry on the National Flood Insurance Program for the coastal regions of U.S., evaluating and reviewing coastal flood hazards. He serves as a senior coastal technical specialist and coastal project manager supporting coastal hazard and resiliency studies.

 

A Human-Nature Coupled Model to Evaluate Land Occupation Dynamics of Coastal Communities

Ayse Karanci

NCSU

akaranc@ncsu.edu

The aim of this study is to investigate the effects of sea level rise (SLR), storm intensity, and soft-engineered coastal protection projects on household occupation/abandonment decisions. The interaction between human decisions and morphological conditions of the coast are linked in an integrated community viability decision support system. To inform management decisions, researchers have developed tools such as Beach-fx, which evaluates both economic and physical consequences of coastal protection measures, but does not address the coupled evolution of engineered landscapes and human behavior. There are models that employ human-nature coupling but do not model morphological change.

Using agent-based modelling (ABM), this study establishes a bottom-up analytical framework that links natural and human systems. It 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 ABM encompasses three submodels:

– Physical environment submodel (PES): accounts for the morphological features in a coastal community. It contains series of alongshore cells with sub-aerial morphology specified by beach width, beach slope, and the height and width of a trapezoidal shaped dune. For each alongshore cell, these values were determined from lidar data.

– Household submodel (HS): employs three types of heterogeneous agents: homeowners , homebuyers , and house sellers to mimic individuals decisions to buy/sell property and buy/not buy insurance. Their occupation decisions depend on community attractiveness, which is a function of expenses (protection costs, flooding damage and insurance), flood risk perception, community size and amenities. Each parcel has its own land use, distance to shore, first floor elevation, structure age, land and property value (Overton et al., 1999).

– Protection submodel (NS): simulates a town’s decision process to undertake a soft-engineered protection project, the design and implementation of the project.

In this study, the described ABM model is used to illustrate the coupled effect of SLR and storms on occupation/abandonment dynamics at Town of Nags Head by performing 50-year length simulations with different incoming storm patterns. Results indicate that feedbacks between natural and human systems are important to understand community dynamics. The frequency and intensity of storm events can change a coastal town’s occupation dynamics and coastal protection trends, and introduce the possibility of community decline.

Ayse Karanci is currently a Ph.D. student in Department of Civil, Construction, and Environmental Engineering at North Carolina State University. Her PhD Dissertation aims to better understand the dynamics between coupled human and physical systems in coastal areas. She is affiliated with the NCSU-Kenan Natural Hazards Mapping Laboratory. Her primary interests include modeling coastal processes, hazard management in coastal areas, and climate change.

 

Gandy’s Beach Coastal Processes

Victoria Curto

Mott MacDonald/Coastal and Hydraulic Engineer

victoria.curto@mottmac.com

Gandy’s Beach is located on the north side of Delaware Bay in New Jersey. It is approximately 0.75 miles long and it consists of more than 60 houses located on Cove Road which runs parallel to the shoreline. Historical aerial photographs indicate the presence of a beach around 1930 which has progressively eroded over time. The shoreline retreat has reduced the subaerial beach extents. An existing seawall has protected to some extent the structural integrity of some houses as well as Cove Road. Nonetheless, these coastal structures continue to experience damage from undermining, storm surge, and wave impact. Additionally, the seawall and shoreline retreat has led to loss of subaerial sandy beach which is important habitat for horseshoe crabs, an important component of the red knot’s (a recently listed endangered species) diet.

A coastal engineering analysis was conducted to develop an understanding of the processes controlling morphology of the Gandy’s Beach shoreline. The overall understanding of the Gandy’s Beach coastal processes is the foundation for development of solutions to meet the project goals. Historical aerial photographs were used to derive shoreline change rates to quantify historical shoreline morphology. The average shoreline change rate is 2.5 feet per year of shoreline retreat, with wide variability in time and across the project site. The existing sea wall has been effective in preventing shoreline retreat. However, sediment at the base of the sea wall continues to be removed from the underwater profile potentially compromising stability for the seawall.

Numerical modelling of nearshore hydrodynamics and sediment transport processes indicate the morphology of Gandy’s Beach is controlled primarily by waves from the ocean moving through the Delaware Bay and wind waves from the south-southwest which combine to generate net sediment transport towards the northwest. The overall northwest trend remains unchanged independent of the season. Evaluation of the hydrodynamics generated by the Delaware River at Gandy’s Beach indicates the Delaware River has a negligible contribution to shoreline morphology.

Nearshore sediment transport processes were examined using the one-line shoreline morphology model GENCADE. The calibrated and validated model was used to determine long term sediment transport patterns and project future shoreline changes. The projected future shoreline condition shows advanced erosion on the terminal ends of seawall and along Gandy’s Beach shoreline.

Victoria Curto is a professional civil engineer registered in California specializing in coastal and hydraulic engineering. She attended UCLA and obtained a B.S. in Civil Engineering and a minor in Atmospheric and Oceanic Sciences. In Los Angeles, she worked as a water resources engineer in the areas of hydrology, hydraulics, and environmental compliance of flood control capital projects. After 5 year tenure, she moved to Delft, Netherlands where she obtained a M.Sc. in Hydraulic, Coastal Engineering from TU Delft and completed her M.Sc. thesis in Deltares. She is currently practicing in New Orleans, LA under Mott MacDonald’s coastal practice.

 

Offshore Wind – A Closer Look

Nicholas DeGennaro PhD PE

D&D Civil and Marine Engineering

ddcivil@yahoo.com

Offshore wind power generation is certainly achievable from the engineering prospective and the wind resource is available. However an important question to address may be; is off shore wind practical?

One of the important driving forces enlisted to advance the implantation of off shore wind is a beneficial outlook for the environment, namely a reduction of carbon emission. There are also additional environmental and social economic considerations that my offset and even turn the balance against a beneficial reduction of carbon emissions.

This presentation will assess some of the important factors that must be reviewed before implementation a comprehensive offshore wind program. These considerations will include the construction and decommissioning of the turbine towers, the transport of the nacelles and blades, the impact to navigation and fisheries, onshore infrastructure necessary to receive the generated power as well as the port infrastructure to support the offshore construction and maintenance. Finally the size and availability of the support ships that must be used to set the foundations and the nacelle will be discussed.

Dr. DeGennaro has varied experiences in coastal engineering which includes 23 years of construction, construction management and design experience His education includes a Masters degree in Ocean Engineering from the University of Rhode Island with a concentration in coastal structures and Doctorate in Civil Engineering from the University of Rhode Island with a concentration in Coastal Hydraulics. Over the last 23 years, Dr. DeGennaro has been responsible for the design and construction management of major marine/environmental construction improvement projects involving the many types of coastal engineering projects throughout the coastal US , Caribbean and the Middle East.

Second Author: Frank Gable Ph.D., Assistant Professor, Florida Gulf Coast University. fgable@fgcu.edu

5C — Lessons Learned From Sandy ● Monmouth 5

 

Some lessons after Storms Sandy and Katrina

William Murphy

e4sciences

wfm3@4sciences.com

The vast majority of us as human beings save our concern for natural processes and the overall environment during the short time interval after a major catastrophic event. We do not often prepare for these black swan events before they happen. Our reaction has been to recover to the vulnerable state, and rarely do we hedge against the shortfalls in our strategy before we are struck again. We have been involved after Sandy in New York/New Jersey and after Katrina in Louisiana. The response efforts in both cases have common characteristics. These efforts offer us the opportunity to learn some lessons. The common characteristics fall into three categories: the natural system, engineering, and solutions.

Solutions

1. Understand the dynamic behavior of the whole system. Monitor behavior with broadband measurements.
2. Let nature do most of the work. Devise solutions that are self-sustaining and work with rather than against the natural processes.
3. Take advantage of the Earth’s immune system. Dynamic beaches and healthy marshes absorb energy.
4. Provide more sand rather than less to the system.
5. Increase capacity for water storage.
6. Build in redundant levels of protection. Level of protection should evolve in time.

Natural system

1. Breaches concentrate locally at the weakest spots. Regional context is crucial but too often forgotten. Temporal context addressed by probability is suspect given small sample and infrequent occurrences. We are dealing with outliers. The stratigraphic record carries unused information.
2. Mass continuity of sediments dominates the behavior in both NYNJ and LA. Bedload dominates sand movement. Suspension dominates mud movement. Account for subsidence, and washover as well as sea level on all frequencies.
3. The system behavior is nonlinear and cannot be divided into subsystems without losing interactions and essential controlling behavior. Marshes provide capacity for mass storage. The absorbing effect of sediments on the shelf is often underestimated.

Engineering

1. Current designs often impede the sediment movement that is nature’s way of healing the beaches and marshes.
2. Current modeling for hurricanes has been insufficient. The present paradigm assumes the subsystems can be partitioned and then summed up without loss of essential behavior.
3. The quality of the measurements and the breadth of frequencies measured have not been sufficient. The formal standards are a good start. But innovative high quality measurements are required.
4. Multiple objectives are a difficult master. The plans and designs emphasize incremental construction and undervalue maintenance.
5. The present strategy is expensive over the long run. Construction needs to be watched daily. As-built drawings based on measurements should be verified independently.

 

Managing scientist and founder e4sciences, 1998-present; Schlumberger, petrophysicist, rock physics, 1982-1988; Stanford University, PhD geophysics, MS Engineering,1979-1982; Gallie Corporation, 1973-1979. Co-authors – Lisa Stewart, Bruce Ward, Daniel Rosales, William Murphy.

 

Lessons from Super Storm Sandy for Coastal Building Codes

Thomas Wakeman

Stevens Institute of Technology

twakeman@stevens.edu

Super Storm Sandy made landfall on October 29, 2011, devastating the coastline of New York and New Jersey. The path taken by Sandy placed coastal communities and the Port of New York and New Jersey directly in the path of the most damaging part of the storm. Many of the Port’s facilities were damaged, and the entire Port was closed for approximately a week costing billions of dollars. While most of the waterside structures generally made it through the storm because they are designed to withstand horizontal forces and vertical forces associated with ships and cargo handling, there were instances of wave and surge related damage to ancillary structures, equipment, and cargo throughout the port. Most of the major damage within the Port was related to the inundation associated with the 6-8 feet storm surge and high tide that led to water levels in excess of 12 feet above normal.

Following the storm, a study was conducted to determine lessons learned that could improve infrastructure resistance and resilience during future disruptions. The study reviewed the existing design codes to identify how building codes could be improved. The study utilized stakeholder interviews to gather information and to identify the circumstances that led to storm-related impacts. Participants include two federal agencies, two state agencies, a harbor pilot organization, an industrial association, and a private facility operator. Lessons learned from the interviews included recommendations that current designs and procedures be re-evaluated given the new level of storm conditions and that preparations to protect personnel, property, and operations be undertaken before disruptive events (e.g., raising buildings, moving electrical systems up out of the flood zone, and conduct drills to practice predetermined courses of action).

Based on these general recommendations from stakeholders and the review of existing building codes, the study made the following five building code suggestions:

(1) The building codes of the states of New York and New Jersey should be uniform for the entire harbor region and updated to specifically include the Port facilities;

(2) The states should directly reference ASCE 24 for flood resistant design for all port facilities and adopt ASCE 24 for siting of critical utility and mechanical equipment.

(3) The Port Authority should add a Coastal Section to their lease agreements specifically devoted to flood and wave resistant construction and other structural considerations at all waterfront properties.

(4) Private facility owners in the Port and associated waterfront properties should adopt one of the available design documents (e.g. ASCE 24) as their primary source for all storm-related design and identify a reasonable and consistent methodology for incorporating sea level rise into their planned engineering upgrades.

(5) Update flood elevations should be provided in the Civil Guidelines to reflect the updated flood maps.

While storms such as Sandy are relatively rare, sea level rise increases the likelihood that storms capable of having similar impacts will occur in the future. It seems prudent to consider potential upgrades to current design guidelines for coastal infrastructure.

Thomas H. Wakeman III is Research Professor in the Department of Civil, Environmental, and Ocean Engineering at Stevens Institute of Technology, Hoboken, New Jersey. Dr. Wakeman has extensive experience in navigation engineering, coastal hydrodynamics, port infrastructure, and maritime resilience. Previously, he worked for Port Authority of New York and New Jersey and the United States Army Corps of Engineers, San Francisco District. He has a MS in Civil Engineering from University of California, Davis, MA in Marine Biology from San Francisco State University, and a doctorate of Engineering-Science from Columbia University, New York.

Co-authors are Dr. Jon Miller and Mr. Matt Janssen.

 

Reformulating the Long Beach Island Storm Damage Reduction Project in the Wake of Hurricane Sandy

Tom Pierro

CB&I / Director

thomas.pierro@cbi.com

In 2008, the City of Long Beach decided that their coastlines needed a plan that would make the City more resilient to rising water levels and increased storms. There were significant misunderstandings between the City, non-governmental organizations (NGO) and the US Army Corps of Engineers (USACE) on how the shore protection project was to be constructed. The City commissioned a comprehensive coastal protection study that concluded a storm damage reduction protection project was needed along the City’s oceanfront beaches. The study also determined that USACE’s proposed Long Beach Island Storm Damage Reduction Project warrants City support and should be modified to better suit the City’s objectives, in particular, the quantity and quality of sand fill for beach nourishment. The City and NGO’s have always maintained that the quality of sand is of utmost importance and the recreational properties of the beach, especially surfing, must be maintained.

Since completion of the 2009 coastal protection study, the City of Long Beach has supported USACE in completing the limited reevaluation report (LRR) process in order to secure funding and move the project forward. This support allowed USACE to update their storm damage modeling assessment and re-evaluate the volume of sand required for the project using recent surveys. Concurrently, USACE conducted additional geotechnical investigations to better map offshore sand resources and bolster confidence that the borrow areas contain beach compatible sand. The results suggested that beach quality sediments exist among other lesser quality sediments, which will need to be mapped in detail for development of a final borrow area.

In late October 2012, Hurricane Sandy caused severe erosion and deflation of the beach throughout the City. A storm impact analysis using post-storm profiles were the basis for beach repair plans that included repair of the dunes along approximately 1,600 feet east of the boardwalk and 4,000 feet west of the boardwalk using recovered beach sand that was overwashed during the storm. In order to restore access to the beach, 19 Americans with Disabilities Act (ADA) dune walkover structures were designed in compliance with applicable FEMA and NY State Building Codes and constructed in 2014.

In February 2014, USACE finalized the Hurricane Sandy Limited Reevaluation Report (HSLRR) that specifies how USACE plans on providing protection to infrastructure surrounding the beaches within the City of Long Beach. The design within the City’s limits includes a stepped berm with sand at higher elevations closer to the dune to minimize the amount of material placed in the ocean. The plan also includes the reconstruction of 15 existing groins.

Co-authors: Quin Robertson, Jim LaCarrubba.

 

Dune building and maintenance in an Atlantic coast residential area: Lessons learned from Hurricane Sandy and beyond

Christine Pryately

Doeg Creek Limited

doeghouse@gmail.com

Co-authors: Christine Pryately and Steven Heinrich

Sand dunes have historically been part of the beach ecosystem in Sandbridge, a residential area in the southern portion of Virginia Beach, Virginia. The protection afforded homes, roads and other coastal infrastructure by vegetation-stabilized sand dunes is well documented. Due to the effects of multiple storms and the lack of dune rebuilding, much of the dune ecosystem has been lost. Steve Heinrich has been reconstructing dunes over the past 15 years in Sandbridge for individual residents. One such property is Boathouse, owned by Christine Pryately.

This paper catalogs the progress of dune construction, vegetation and maintenance at Boathouse over a 4-year period, beginning in September 2012, just two months before Hurricane Sandy. The dune-building methodology Steve developed was used at this site. Four types of native dune grasses were used to help stabilize and grow both the inner and outer dune, including Sea Oats (Uniola paniculata) and American Beach Grass (Ammophila breviligulata). Photos and descriptions of each step in the building process and photos of neighboring sand dunes following Hurricane Sandy are shared.

The beachfront in Sandbridge is enhanced by sand replenishment. The most recent sand replenishment occurred in early 2013 and another is scheduled for 2017. The effect of beach replenishment on the dune building process, sources and quality of dune construction materials used, tourist interaction, and regulatory issues confronting homeowners and landscape professionals are discussed. Beach access and costs associated with the process are also included.

Regulations currently restrict moving sand onto the beach. However, public benefits resulting from the private investment in dune creation could be significant. Reducing restraints and providing guidelines such as those discussed in this case study, would be helpful in expanding dune creation in Sandbridge.

Christine Pryately is a Master Gardener and has an undergraduate degree in Environmental Science, Master of Science in Environmental Engineering and runs Doeg Creek Limited. Steve Heinrich is President of Seaside Restorations in Virginia Beach.

 

5D — Regional Sediment Management Session 2 ● Atlantic 3

 

Dredging, Sand Management and Habitat Restoration of a Jettied Inlet System, Chatham, MA

Ted Keon

Town of Chatham, MA

tkeon@chatham-ma.gov

Chatham, located at the elbow of Cape Cod, has two distinct littoral systems. One system faces east along the Atlantic Ocean; the other is located on Chatham’s south side facing Nantucket Sound. Cape Cod is devoid of coastal engineering structures along its Atlantic Ocean coast, however, its Nantucket Sound shoreline is characterized by numerous jetties and groins. Nantucket Sound has a dominant west to east littoral sediment flux due to a prevailing southwest wind regime. Chatham, located at the far eastern end of Nantucket Sound receives reduced sediment supply to its beaches as a result.

Mill Creek is a small, narrow jettied inlet located at the eastern end of Forest Beach which is a barrier spit with a groin field, narrow scalloped beaches, and a low dune field. Mill Creek provides tidal flow to a large interior, shallow marsh system and a glacially-formed kettle pond. By 2006, the updrift beach fillet adjacent to the western jetty had become filled to capacity with sand bypassing the jetty tip and into the inlet channel. A large sub-aerial shoal developed across the mouth of the inlet reducing tidal exchange and causing deterioration in water quality and habitat value of the internal ecosystem.

An inlet dredging and sand management program was developed to improve tidal flow and provide for beneficial use of dredged material to address erosion along nearby beaches. The project design included dredging portions of the updrift beach fillet to restore trapping capacity of the western jetty and reduce natural bypassing. However, the area adjacent to the fillet is nesting habitat for Piping Plovers, protected shorebirds under state and federal Endangered Species Acts. Dredging of the fillet received approval conditioned on a unique habitat restoration feature that included removal of a 25m by 165m portion of dune and beach grass vegetation to expand and enhance shorebird nesting habitat.

Dredging the inlet channel to remove the shoal and restore tidal flow was accomplished in 2010. Funding constraints at the time limited the work to channel dredging only, and no work associated with dredging the updrift beach fillet or creation of the shorebird nesting habitat was undertaken. The channel required annual dredging through 2014 since material continued to bypass the western jetty. In 2015 a public/private partnership was established between Chatham and some private homeowners. The homeowners funded dredging of the beach fillet and the habitat restoration in order for the dredged material to be used to address erosion along private shorelines. The project was completed over the winter of 2014-2015 and approximately 11,000 m3 of sand were placed on private beaches at the west end of Chatham. Trapping capacity of the jetty was restored and Plovers successfully nested in the new habitat area during the 2015 nesting season.

Ted Keon is the Director of Coastal Resources with the Town of Chatham, MA, a position he has held since 1998. Mr. Keon is the primary liaison for Chatham’s marine and shoreline related activities. He oversees the planning and implementation of projects affecting Chatham’s waterways, coastal shorelines and water dependent infrastructure and also provides oversight of Chatham’s Town Landings and water related access. Mr. Keon is directly responsible for the Town’s comprehensive dredging, shoreline change and sediment management program.

 

Innovative Recycling of Major Sand Surplus Volumes Instead of Using Virgin Material i.e. (Backpassing) in New Jersey

Stewart Farrell

Stockton University Coastal Center

farrells@stockton.edu

This is a re-examination of classifying chronic areas of sand surplus as recycling borrow zones for erosional hot spots within multiple large-scale beach nourishment regions. Recycling sand supplies is a concept, while sand backpassing is a technique that has been employed at a smaller scope and scale on New Jersey coastal reaches. Chronic erosion and oversupply form a series of problematic reaches along the entire shoreline. Few worry over chronic oversupply to an area, but this excess supply becomes a potentially valuable resource to an adjacent beach area where loss dominates.

Hydraulic dredging inlet or offshore borrow zones comes with a $2.5 million dollar price tag for mobilization costs. These costs have greatly escalated over the past decade, pushing the maintenance of projects ever higher. The recycling of sand supplies will vary depending on the desired final volume involved with each operation.

1) Six projects below 100,000 cubic yards have utilized high capacity trucks loaded with an excavator and graded in place with a bulldozer. Mobilization costs about $80,000 with a $5-$7/cubic yard hauling rate.

2) Fixed assets in the form of a pumping station, pipeline and an eductor dredge and crane have been in service since 1988 at Indian River, Delaware with operational output of 61,000 cy/year (2013-5 data since Hurricane Sandy with less surplus sand available). Original goal was 100,000 cy/year.

3) Inlet dredging using hopper dredges with sand placement along nearby shorelines is an established process, done as far back as 1978 at Barnegat Inlet.

4) Thinking on a bigger scale, since the NY Army District commenced the Monmouth County beach restoration project, over 3 million cubic yards of new sand has been added to Sandy Hook just between the park entrance and Gunnison Beach (CRC, 2011). Design a fixed asset installation to extract sand from the tip of Sandy Hook and pump it back at least as far as Sea Bright’s municipal beach. Major components would be an eductor dredge on a crane, buried supply pipeline and multiple booster pumping stations along the way. Winter operations limit wildlife impacts.

Backpassing does require more frequent deployment since most zones of sand loss are reduced by 100,000 to 150,000 cubic yards per year and the most cost effective means of resource allocation is to use the high capacity trucks driven on the beach offseason. The borrow zone becomes the accretional berm and beachface with between 1 and 3 foot deep cuts pushed into a linear ridge where the excavator sits and loads trucks that haul 20 to 25 yards of sand per trip to the zone of chronic loss. This prospect appears to work best on NJ barrier islands where each island has a zone of accretion and usually a zone of chronic loss. The best data on actual projects competed comes from Avalon and North Wildwood in Cape May County. Avalon has 4 projects since 2005 moving 221,119 cubic yards at a cost of $1,359,125 ($6.18/cu. yd.), and North Wildwood has 3 projects since 2012 moving 221,486 cy at a cost of $1.74 million ($7.85/cu. yd.).

Dr. Stewart Farrell is the Executive Director at the Stockton University’s Coastal Research Center. PhD in 1972 in Coastal Processes of Saco Bay, Maine, Professor Marine Geology, Stockton University 1971 – 2010.

 

CMS Modeling of the North Coast of Puerto Rico

Kelly R. LeGault

USACE, Jacksonville District

kelly.r.legault@usace.army.mil.

1. Introduction

The goals of the San Juan, Puerto Rico Regional Sediment Management (RSM) study are to isolate where erosion problems exist, what their causes are and coordinate with stakeholders to formulate and implement strategies to mitigate shoreline erosion and maximize beneficial use of sediment where appropriate. Because the north coast of Puerto Rico is a series of pocket beaches with a diverse shoreline features, it is necessary to study the shoreline at an appropriate spatial resolution to resolve the mean nearshore current structure. The Coastal Modeling System (CMS), which is an integrated 2D numerical modeling system for simulating waves, current, water level, sediment transport, and morphology change at coastal inlets and beaches was used to examine salient horizontal current structure for the north shoreline of Puerto Rico. The study area extended approximately 50 miles from west of San Juan (Vega Baja) to east to Luquillo. Mean nearshore currents were examined for convergences, divergences and dominant transport direction to indicate regions that would be favorable placement areas for beneficial use of sediment.

2. Study Procedure

The USACE Regional Sediment Management (RSM) program funded a coupled wave and hydrodynamic modeling study of the north coast of Puerto Rico to determine coastal regions that may prove to be suitable placement areas. The Coastal Modeling System (CMS) was used to calculate nearshore currents that are forced by waves and tidal currents. The CMS Flow and CMS Wave grid spanned approximately 50 miles alongshore and was forced with astronomical tides and Caricoos Buoy at San Juan. The model was calibrated and verified with AWAC data collected in the nearshore.

3. Selected Results

It was found that the strength of the coastal currents are, as expected, strongly correlated with incoming wave energy as well as surface gradients in the nearshore. Onshore flows are indicated by the mass flux of water over the coral reef and offshore flows are found in the gaps of the reef. Seasonal cycles of alongshore transport in pocket beaches with bi-annual reversals are found due to the Trade Winds. Selected locations for sediment placement were sought at locations where divergences existed and where offshore flows were not dominant.

Dr. Legault is a Senior Coastal Engineer with the USACE, Jacksonville District. Dr. Legault received her Ph.D. in Ocean Engineering in 1997 from Stevens Institute of Technology. She was an Assistant Professor at Stevens where her work focused on coastal structures and their impact on sediment transport and nearshore circulation; Coastal Scientist with Ocean and Coastal Consultants focusing on coastal flood hazards; Research Engineer at Naval Research Laboratory where developing protocols for the treatment of ship ballast water for nuisance species. She was a fellow at the Laboratory for Marine Biological Sciences at Woods Hole Oceanographic Institution.

 

A Regional Sediment Management Approach to Coastal Projects: Restoring Navigation and Enhancing Coastal Resilience following Hurricane Sandy

Monica Chasten

USACE, Philadelphia District

Monica.A.Chasten@usace.army.mil

The U.S. Army Corps of Engineers (USACE), Philadelphia District has been participating in the national Regional Sediment Management Program (RSM) for over twelve years demonstrating significant accomplishments using sediment as a resource and developing strategies for future dredging and placement activities. After Hurricane Sandy impacted the Philadelphia District region, a need existed to remove critical shoals that were impeding navigation while at the same time adjacent beaches and environmental resources required repair. Navigation managers from the Philadelphia District took a proactive approach and quickly partnered with USACE’s Engineering Research and Development Center to utilize RSM and Engineering with Nature (EWN) strategies for post-Sandy recovery efforts. Post-storm dredging of federal coastal channels and placement operations began in December 2012 and continued through March 2016.

Several examples of recent projects that utilized dredged material to replenish shorelines and restore wetlands in New Jersey will be presented including marsh restoration projects near Mordecai Island, Ring Island, Avalon and use of the shallow draft government dredges to support beach nourishment. Design and construction techniques for these projects will be discussed. Monitoring is ongoing and lessons learned are being developed that will contribute to long-term RSM strategies and the implementation of future projects that continue to build coastal system resilience for the region.

Ms. Monica Chasten is a Project Manager with the U.S. Army Corps of Engineers, Philadelphia District, Operations Division. She has over 30 years of experience with hydraulic and coastal engineering projects specializing in such areas as channel dredging, beach nourishment, inlet analysis, regional sediment management and coastal structures. Ms. Chasten’s current responsibilities include serving as the Project Manager for Coastal Navigation projects in NJ and DE and for the Northern Area Flood Damage Reduction projects in Pennsylvania. Ms. Chasten received a B.S. in Civil Engineering from Drexel University in 1987 and an M.S. in Hydraulic and Coastal Engineering from Lehigh University in 1989.

5E — Beach Restoration: Building Resiliency ● Atlantic 4

 

The Misquamicut (Rhode Island) State Beach Replenishment Project: Two years Later, Measured Using RTK-GPS, DGPS and Beach Profiles

Bryan Oakley

Assistant Professor, Eastern Connecticut State University

OakleyB@easternct.edu

The U.S. Army Corps of Engineers added more than 65,000 m3 (86,000 yd3) of sediment to the berm of the 1 km Misquamicut State Beach (MSB), located on the Rhode Island south shore in May 2014. We have been monitoring the replenishment using near-monthly beach profiles and mapped position of last high-tide swash (LHTS) and quarterly RTK-GPS topographic surveys for >2 years since replenishment. Comparing interpolated surfaces generated using RTK-GPS points indicates that 20% of the placed volume was eroded in the first three months, mostly during periods of high wave energy associated with offshore (non-landfalling) tropical cyclones. 35% of the placed sediment volume on MSB has been lost as of March 2016. The digital elevation model derived from U.S.G.S. LiDAR collected in March 2014 and the post-replenishment surfaces show good agreement between the measured increase in volume (62,000 m3) and nominal volume (65,000 m3), suggesting that comparisons between the RTK-GPS derived surfaces and airborne LIDAR elevation models are valid, and gives confidence to the interpolated RTK-GPS derived surfaces.

Erosion has not been uniform along MSB; the western portion has seen little change in volume. However most of the added volume has been lost from the central and eastern portion of MSQ, and as of March 2016 profiles are +/- 3% of pre-replenishment volumes. Tracking volume lost as a percentage of the berm volume or berm width produces similar results. Repeat side-scan sonar surveys of the upper shoreface in 2008/2015 show little change in the extent of the nearshore depositional platform, at least qualitatively suggesting much of the eroded sediment has not been transported offshore. The mapped position of LHTS coupled with field observations suggest that longshore transport has been complicated, however at least some of the eroded sediment has likely been transported east to the flood-tidal delta of the adjacent coastal lagoon.

Our working hypothesis is that the shoreface topography focuses wave energy onto the more erosional segments of MSB. Pre-replenishment orthophotography shows the berm is consistently narrower here, and points to the importance of understanding the shoreface processes and local shoreline orientation when designing replenishment projects. The lack of major storms during the two years since replenishment and net loss of >35% is an important consideration when planning future replenishment projects along this shoreline. The high cost 3.1 million dollars of the project ($47 m-3 ($36 yd-3) is due to the sediment source (upland glacial stratified deposits). With the exception of beneficial reuse of sediment dredged from tidal inlets, offshore sources are not used in RI. While common elsewhere, replenishment at this scale has been rare in Rhode Island. Replenishment will likely will become a more common practice as shoreline change continues to impact developed shorelines, and efforts to located offshore sediment sources in Rhode Island are underway. Understanding the efficacy of these projects is vital to understanding the net benefit and longevity of replenishment in the future.

Bryan Oakley joined the Environmental Earth Science Department at Eastern Connecticut State University in August 2012, Oakley works closely with the Rhode Island Coastal Resources Management Council on a variety of issues regarding erosion and shoreline change. On-going projects include; updating the current shoreline change maps for Washington County, RI, mapping portions of the Rhode Island nearshore in examining links between the shoreface and shoreline change, examining erosion on Block Island, mapping seafloor habitats offshore of Branford, CT, the Late Wisconsinan and Holocene evolution of Cape Cod and monitoring shoreline change at Napatree Point, RI.

 

Beach Nourishment in Galveston Texas- A Long Term Plan for Success

Reuben Trevino

Galveston Island Park Board of Trustees; Director of Operations

rtrevino@galvestonparkboard.org, pbadmin@galvestonparkboard.org

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 6,000,000 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 6,000,000 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 five (5) year plan as identified in Galveston Island, Texas, Sand Management Strategies 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 5-year plan identifies projects, grant applications, partnerships, locations, tentative volumes, and potential construction calendars for specific projects. Included in the presentation will be a review of recent, current, and planned beach nourishment projects detailing planning considerations, implementation difficulties, potential unintended consequences and their relationship/impact to other beach 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.

Reuben has been an Eagle Scout since age 15, where his experiences led to his concern for preservation and restoration of the great outdoors, and more specifically our coastal areas. Trevino participated in multiple research projects while earning a BS and Masters in Biology. He is a certified TX Master & Coastal Naturalist, and former member of the TX Sea Grant Advisory Committee. He worked for the City of South Padre Island from 2008 – 2015 managing their Coastal Resources Program. In February 2016 he accepted a position with the Galveston Park Board of Trustees as the Director of Operations.

 

Beach Restoration on Dauphin Island, Alabama

Scott Douglass

South Coast Engineers/President

scott@southcoastengineers.com

The 2015-2016 Dauphin Island East End Beach and Barrier Island Restoration Project – the first major engineered beach nourishment project in the island’s 300+ year history – has been a tremendous success. The project included both beach nourishment and nearshore breakwaters. This presentation will summarize the entire process from initial planning, feasibility-conceptual design studies, sand searches, funding, permitting, final design, through construction and performance to date.

The nourishment project restored a mile of beaches with 320,000 cubic yards of beach quality sand. The new beach placement template was almost 400 feet wide at the eastern end of the project. This beach had experienced significant erosion, up to 700 feet of shoreline recession, in past decades. The beach serves as protection to highly valuable maritime forest and freshwater lake habitat in an Audubon Bird Sanctuary. The primary purpose of this project was to protect, restore, and preserve those natural barrier island habitats. Other benefits of the project include storm damage protection for the Dauphin Island Sea Lab and Fort Gaines – one of the two forts at the mouth of Mobile Bay during the 1864 Battle of Mobile Bay, during which Admiral Farragut famously cried, Damn the torpedoes! Full speed ahead! The new beach also has become the most popular beach on the island since nourishment – for both residents and visitors. Indeed, the new beach has already become part of the fabric of society – a wedding was held on the new beach the first weekend after construction concluded with the groom asking the Mayor for permission to start a new chapter in our lives on our new beach!

The project was first envisioned in a beach management plan developed by the Town in 2009 as one of three things that needed to be done to save the island’s beaches. Sand search investigations in 2010 and 2011 identified the borrow area with white, large-grain sands about 4-5 miles offshore. Permitting included detailed study of the borrow area for avoidance of any archeological treasures (a shipwreck graveyard). Construction took place from October 2015 to March 2016. The project includes three new, nearshore, segmented breakwaters at its eastern end to retain the new sand longer. The three new structures were built with recycled rocks from a circa 1907 groin field at that same location that had suffered so much shoreline recession that all nine of the former groins were flanked and had been surrounded by water for decades. The old rocks were picked up, realigned parallel to shore, and topped with some larger new rocks to construct the new shore-parallel breakwaters. The contractor was Weeks Marine and construction was funded by the Alabama Department of Conservation and Natural Resources with Coastal Impact Assistance Program (CIAP) funds.

Scott Douglass is a director of ASBPA and the founder of South Coast Engineers, a coastal engineering and science consulting firm in Fairhope, Alabama. He is an Emeritus Professor at the University of South Alabama, the author of Saving America’s Beaches: The Causes of and Solutions to Beach Erosion, and is the developer-author of the FHWA’s primary guidance documents for the planning and design of coastal highways: HEC-25 Highways in the Coastal Environment and HEC-25, volume 2: Highways in the Coastal Environment: Assessing Extreme Events.

 

Building Resilience for Coastal New Jersey, North of Manasquan Inlet

Roy Messaros

USACE, New York District

roymessaros@aol.com

The New York District conducted a beach erosion control study titled The Atlantic Coast of New Jersey, Sandy Hook to Barnegat Inlet (1954) focusing on shore history, geomorphology, and littoral materials and forces. The study area includes approximately 21 miles of shoreline (adjacent to Manasquan Inlet, surrounding Shark River Inlet), mainland beaches from Manasquan to Long Branch, and a barrier-spit landform from Monmouth Beach and Sea Bright. Initial construction for the majority of the project shoreline took place from 1994 to 2000. Four partial renourishment events were conducted between 2002 and 2014. As a result of the Hurricane Sandy Relief Bill (2013) for building coastal resilience funding was made available for additional project work. The remaining portion of the 21 mile study area that has never had a beachfill is Elberon to Loch Arbour (from Deal Lake to Lake Takanassee). The current beach restoration project for Elberon to Loch Arbour includes a beach berm to be constructed with 4,450,000 CY of sand obtained from the permitted Sea Bright Borrow Area (SBBA). To allow for required sediment transport and reduce impoundment, three existing groins will be modified (notched). As the constructed beach will be wider than current conditions, the project also includes improvements to eighteen outfalls within the constructed reach of beach, including ten outfall extensions, seven preformed scour holes, and one retention system. Details of the project will be presented as well as an available sediment budget and transport for Manasquan Inlet to Sandy Hook. Aspects of the long-term coastal resiliency efforts by the New York District will be discussed.

Roy Messaros’ primary focus involves coastal hydraulics for the Hurricane Sandy Relief Branch with the US Army Corps of Engineers. Responsibilities include using Coastal Engineering Modeling (CEM) software to assist with the design of flood control structures (levees/floodwalls) such as those present in the Port Monmouth Storm Surge Protection project. Perform floodplain analysis studies using Hydrologic Engineering Center – River Analysis System (HEC-RAS) and Hydrologic Modeling System (HEC-HMS) software. Contribute to the Jamaica Bay (Brooklyn/Queens, NY) marsh island mitigation/restoration, construction/monitoring and acted in a dual capacity as project engineer and hydraulic (design) engineer for this interagency, multimillion-dollar project to restore the Elder’s Point tidal marsh habitat.

5F — A Tribute to Orville Magoon ● Atlantic 5

 

Orville Magoon: Contributions to Coastal Structures Engineering

Thomas Kendall

SF District Corps of Engineers

Orville Magoon was engaged in coastal engineering most of his life. Through his career with the U.S. Army Corps of Engineers and as Chief of the Coastal Engineering Branch, he was involved with a variety of coastal engineering projects including the Humboldt jetties and the Crescent City outer breakwater. These structures are exposed to a severe wave climate with depth-limited waves on an annual basis. After decades of repeated major repairs to the battered Humboldt Jetty heads using a variety of geometries and armor types, in the early 1970’s Orville was given the challenge to ‘fix it once and for all’. He traveled the world examining jetty and breakwater successes and failures and came up with the proposal to try dolos armor units for the first time in the US. With the units weighing in at 42 tons each, Orville personally insisted that the dolos units be reinforced ‎in spite of external pressures to save money and use the traditional approach with unreinforced units. The research, planning and design began in 1971 (and was completed by 1986). To this day, the jetty heads have generally only needed minor repairs.

Orville remained influential in promoting safe coastal structure design following his retirement from the Corps of Engineers. He chaired a number of workshops and symposia on berm breakwaters, case histories of rubble mounds, monitoring of breakwaters, stresses in concrete armor units and advances in coastal structure design, co-editing the proceedings. He carried the torch for coastal structures promoting safe yet innovative design and documenting coastal structure failures. He was a significant voice in the field of coastal engineering and especially coastal structures at a time when the field was advancing at a harried pace. That voice will surely be missed in the coming decades.

Co-authors: Jeffrey A Melby, Coastal and Hydraulics Laboratory ERDC, Billy L. Edge, UNC-Coastal Studies Institute

 

Carbonate beaches are under attack: Multiple sources of dissolution of the sand from sea, land and air

Lisa Robbins

U.S. Geological Survey

lrobbins@usgs.gov

Since the industrial revolution, the incrementally increasing level of atmospheric carbon dioxide has not only lowered the pH of the oceans (ocean acidification) and impacted the ability of many calcium carbonate producing organisms to create their shells, but has had concomitant effect of lowering the pH of rainfall, a process that has been linked to dissolution of limestone buildings and structures and creation of karst. The former process has serious consequences in diminishing carbonate skeletal and non-skeletal production of organisms and therefore sediment production, and the latter ultimately in affecting the dissolution of carbonate sediment deposited onshore. Although both of these processes are global, they each are controlled by local pCO2 variations that will affect carbonate production and dissolution rates.

In the tropics, many marine plants and animals (Halimeda, corals, foraminifera, echinoderms, gastropods, mollusks, etc.) produce carbonate skeletons and components that break down into sediment grains and subsequently are deposited as beach sands. In temperate and polar climates, cold water skeletal carbonates (dominated by mollusks, echinoderms and gastropods) can comprise a substantial component of siliciclastic beaches. The skeletal and non-skeletal carbonates on beaches from tropics to poles are vulnerable to chemical dissolution, whether it be from ocean acidification, freshwater acidification or acid rain.

From a sediment budget perspective, in the tropics and subtropics, the consequence of these processes working in concert may have significant impact on beaches that contain pure carbonate sands. In temperate and polar climates, where there are mixed siliciclastic- carbonate beaches, the carbonate components will diminish, eventually leaving only siliciclastics.

As atmospheric CO2 rises, management practices of our increasingly vulnerable carbonate- bearing beach deposits will be directly impacted. Carbonate beaches will be discussed as a function of production rates of different carbonate skeletal organisms as source material for the beaches and in combination with a model of onshore dissolution as a consequence of acid rain.

Lisa L. Robbins, PhD.: Robbins is a Senior Scientist at the U.S. Geological Survey (USGS) in St. Petersburg FL studying ocean acidification in coastal and marine waters and its effects on sediment producing organisms and therefore sediments. She received her Ph.D. in Marine Geology and Geophysics at the Rosenstiel School of Marine and Atmospheric Science- University of Miami and a Bachelor of Science in Geology at Vanderbilt University. Prior to USGS, she was a Professor in Geology at the University of South Florida for 11 years.

 

Waikiki Beach Management: Past, Present and Future

Robert Walker

Hawaii Chapter, ASBPA

Co-authors: Roberto Porro (1,2), Dolan Eversole (3), Robert Walker (4,5), and Michael Foley (6)

1 Department of Urban and Regional Planning, University of Hawaii at Manoa

2 National Disaster Preparedness Training Center, University of Hawaii at Manoa

3 University of Hawaii Sea Grant College Program

4 Department of Geology and Geophysics, University of Hawaii at Manoa,

5 Shoreline Science & Engineering, LLC

6 Oceanit Laboratories, Inc.

Orville T. Magoon grew up along the shores of Waikiki in Honolulu, Hawaii during the early 1900’s. This was a time period of rapid growth and development for an area that once consisted of wetlands, taro fields, and Hawaiian fishponds. The Waikiki that we know today serves as the economic hub of the tourism industry, accounting for as much as 40% of the State’s tourism activity. However, maintaining the quintessential white sand beaches of Waikiki among increasing threats of coastal hazards and urban development proved to be a challenging effort over the twentieth century. Anthropogenic activities such as the removal of coral and carbonate sands for navigation and construction purposes, introduction of coastal structures such as groins and seawalls, beach nourishment activities, and coastal development have resulted in what is now a heavily engineered stretch of shoreline. Many of these activities have been implemented by an uncoordinated mix of public and private projects over the last century that have often failed to consider the cumulative impacts to the nearshore environment.

As a recognized leader in issues of coastal zone management and the sustainability of beaches, Orville T. Magoon passionately followed many coastal management projects in Waikiki over the course of his lifetime. In March 2016, the Hawaii Chapter of the American Shore and Beach Preservation Association (HSBPA) was pleased to have the opportunity to welcome Orville and Karen Magoon for a special meeting in Waikiki during what would be their last trip to the islands together. During the meeting, Hawaii chapter members honored Orville for his contributions to coastal science and engineering in Hawaii, and took this opportunity to provide an update on beach preservation efforts in Hawaii including coastal management along the Waikiki shoreline. We continued discussions during a site walk where we discussed some specific contemporary issues including the disrepair of the historic Waikiki Natatorium War Memorial and the adjoining Queen’s Beach seawall. We discussed how future improvement projects such as these can benefit when viewed from a more holistic perspective that considers the entire impacted shoreline. Special Orville Magoon Session ASBPA Conference October 25 – 28, 2016 in Long Branch, New Jersey This presentation will provide an overview of beach management in Waikiki over the lifetime of Orville Magoon. We will report the results of recent research at the University of Hawaii aimed at examining the benefits and challenges of beach erosion strategies, intended to help inform any future regional beach management plans for the Waikiki shoreline. We will also provide an update on the future of beach management in Waikiki, including the establishment of a special tax district to help generate funds for beach management efforts in the area, as well as a new Waikiki Beach Coordinator position recently established at the University of Hawaii Sea Grant College Program to oversee and coordinate beach management efforts of the iconic shoreline among various stakeholder groups. The presentation will incorporate selected Waikiki case studies to help introduce some of the complex and site-specific historical, cultural, societal, and economic factors as they relate to coastal zone management decisions within the Waikiki region.

Robert Walker is a coastal engineer and researcher located in Hawaii. Areas of active research include coastal processes of reef-lined shorelines and the incorporation of natural elements to shoreline preservation and coastal hazard mitigation.