15 Oct 2025

An Investigation into the Correlation Between Selected Coastal Protection Indices and Percent Residual Dune and Berm Volumes Following Coastal Storms

Abstract: Morphometric indices describe the dimensions of a dune and berm profile and can serve as relative metrics of coastal protection. However, coastal vulnerability to storm damage also depends on storm, wave, sediment, and offshore characteristics. Recently, more elaborate non-morphometric indices have been proposed in an effort to account for these other factors. This study compares the correlation between these morphometric and non-morphometric indices and one measure of coastal protection, the ability of a dune and berm profile to resist storm-induced changes in volume. This study uses a numerical-simulation approach rather than an empirical approach because a sufficiently comprehensive set of observational data does not exist. A randomized sample of dune and berm profiles were generated at eight coastal locations. Using the cross-shore numerical model (CSHORE), storm-induced changes in dune and berm volume were simulated for storms of low to moderate severity. The correlation between the various prestorm indices and the percentage of prestorm dune and berm volume remaining after the storm was calculated at each location. Results show that no single index always exhibits a higher correlation with percent dune and berm volume remaining. However, some indices were far more likely than others to produce higher correlations.

1 Oct 2025

Numerical Storm Surge Modeling and Probabilistic Analysis for Evaluating Proposed New Jersey Back Bays Inlet Closures

Abstract: The US Army Corps of Engineers, Philadelphia District, and the New Jersey Department of Environmental Protection are currently engaged in the New Jersey Back Bays (NJBB) Coastal Storm Risk Management Feasibility Study. The US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, conducted a numerical hydrodynamic modeling and probabilistic hazard analysis study to evaluate the effectiveness of storm surge barriers in reducing water levels in the NJBB. The numerical modeling study included the simulation of water levels and a comparison of water surface elevations and corresponding annual exceedance frequency between existing conditions and six final project alternatives. Results from the hydrodynamic simulations and probabilistic analysis are presented herein.

28 Aug 2025

South Atlantic Coastal Study (SACS) Calibration and Validation of the Coastal Storm Modeling System (CSTORM) for Water Levels and Waves Part 3. Gulf of Mexico Domain

Abstract: The US Army Corps of Engineers, South Atlantic Division, is currently engaged in the South Atlantic Coastal Study. One of the phases of this study is focused on conducting coastal storm modeling for the eastern and central Gulf of Mexico coastline of the United States. This technical report details the development of input for the Coastal Storm Modeling System (CSTORM) suite of models (WAVEWATCH III, ADCIRC, and STWAVE) for this project and presents the efforts made to calibrate model setups and validate results for eight historical tropical storm events impacting the study area.

28 Aug 2025

South Atlantic Coastal Study (SACS) Calibration and Validation of the Coastal Storm Modeling System (CSTORM-MS) for Water Levels and Waves: Part 2. South Atlantic Coast Domain

Abstract: The US Army Corps of Engineers, South Atlantic Division, is currently engaged in the South Atlantic Coastal Study. One of the phases of this study is focused on conducting coastal storm modeling for the southern Atlantic coastline of the United States. This technical report details the development of input for the Coastal Storm Modeling System suite of models (WAVEWATCH III, ADCIRC, and STWAVE) for this project and presents the efforts made to calibrate model setups and validate results for seven historical tropical storm events impacting the study area.

28 Aug 2025

South Atlantic Coastal Study (SACS) Calibration and Validation of the Coastal Storm Modeling System (CSTORM-MS) for Water Levels and Waves: Part 1: Puerto Rico / US Virgin Island Domain

Abstract: The US Army Corps of Engineers, South Atlantic Division, is currently engaged in the South Atlantic Coastal Study. One of the phases of this study is focused on conducting coastal storm modeling for the Puerto Rico and US Virgin Islands. This technical report details the development of input for the Coastal Storm Modeling System suite of models (WAVEWATCH III, ADCIRC, and STWAVE) for this project and presents the efforts made to calibrate model setups and validate results for four historical tropical storm events impacting the study area.

17 Jul 2025

Overview of the Coastal STORM (CSTORM) Model Development for the Swan Island Restoration Study

Abstract: This document summarizes the numerical model development and validation approach used to simulate the winds, waves, and water levels observed at Swan Island during two prominent historical storm events in the region: Hurricane Sandy and Hurricane Isabel. Using the Coastal STORM (CSTORM) Modeling System, which couples the Advanced Circulation (ADCIRC) and Steady-State Spectral WAVE (STWAVE) models, the North Atlantic Coast Comprehensive Study mesh and grid were refined in the area surrounding Swan Island. The nodal attributes of the ADCIRC mesh in the area surrounding Swan Island were updated to reflect the location of submerged aquatic vegetation around the island. ADCIRC-modeled water levels were in acceptable agreement with observed water levels during both storms, though peak water levels were slightly underpredicted. Similarly, STWAVE captured the phase and trends of the significant wave heights during the storm, while slightly underpredicting both significant wave height and peak period. The validated model will be used to investigate the effect of the restoration of Swan Island on the surrounding area. The results will help to develop guidelines for best practices in island restoration within the Chesapeake Bay and beyond.

5 Jun 2025

Incorporating Natural and Nature-Based Features in an Urban California Creek Through Application of Engineering With Nature® Principles

Purpose: Since its launch in 2021, the Engineering With Nature® (EWN®) program has funded research focused in a variety of environments, particularly along marine and freshwater coasts and fluvial (riverine) systems. Until recently, there has been less focus on applying EWN principles in urban landscapes and watersheds to help manage flood risk, a main civil works mission of the US Army Corps of Engineers (USACE). Natural hazard challenges, including intense rainfall events, are contributing to flooding and prompting the need for more sustainable infrastructure to reduce flood risks in urban areas. This is especially relevant when such nature-based solutions (NBS) are desired by stakeholders who stand to benefit from the project. This technical note documents a USACE Chicago District (LRC) project that supports USACE Los Angeles District (SPL) to incorporate EWN principles in an urban ephemeral creek to reduce flood risk while providing other environmental, social, and economic benefits.

3 Apr 2025

Ohio Creek Urban Coastal Storm Risk Management Project: An Application of Engineering With Nature® Principles in Practice

Purpose: The Engineering With Nature® (EWN®) program within the US Army Corps of Engineers (USACE) funds research projects occurring in a myriad of environments, including in marine coasts, freshwater coasts, and fluvial (riverine) systems. Yet there have been fewer projects documented where EWN principles have been applied in urban landscapes, particularly to manage flood risk, a main civil works mission of the USACE. Natural hazards including increased flashiness associated with intense rainfall events have prompted the need for more sustainable infrastructure solutions that reduce flood risks in urban areas, especially when such solutions desired by stakeholders are nature-based solutions. This technical note documents a flood risk management project in Norfolk, Virginia, that incorporates EWN principles in a tidal estuary environment that not only reduces flood risk, but also provides numerous other environmental, social, and economic benefits.

13 Feb 2025

Upper Barataria Basin (UBB) Coastal Storm Risk Management (CSRM) Study : Probabilistic and Numerical Coastal Hazards Modeling

Abstract: This report summarizes the numerical modeling and probabilistic analysis performed by the US Army Engineer Research and Development Center Coastal and Hydraulics Laboratory (CHL) as part of the Upper Barataria Basin (UBB) Coastal Storm Risk Management (CSRM) Study. The intent of this work, performed for the US Army Corps of Engineers (USACE) and St. Paul District, was to evaluate project alternatives to assess flooding risks induced by coastal storms in coastal Louisiana. This study applied the USACE’s Coastal Storm Modeling System for storm surge and wave modeling and Coastal Hazards System–Probabilistic Framework (CHS-PF) to quantify water level and wave hazards, leveraging existing synthetic tropical cyclones (TCs) from the Coastal Hazards System¬–Louisiana (CHS-LA) study for levee recertification. Using a reduced storm suite (RSS) of synthetic TCs from CHS-LA, hydrodynamic model simulations were performed on an updated grid, including five proposed levee systems, to produce storm responses at more than 184,000 mesh node locations and over 21000 special save point locations within the UBB project area. Through the application of the CHS-PF, the joint probability analysis of TC atmospheric-forcing parameters and their associated storm responses were assessed for the estimation of still water level (SWL), significant wave height (Hm0), and wave peak period (Tp) annual exceedance frequencies ranging from 10 to 1 × 10−4 yr−1 to evaluate the impact of the UBB with- and without-project conditions.

28 Nov 2023

Total Water Level Controls on the Trajectory of Dune Toe Retreat

Abstract: This study examines the trajectory (slope) of coastal foredune toe retreat in response to nine storm events that impacted the Outer Banks, North Carolina, USA. High resolution, three-dimensional, repeat mobile terrestrial lidar observations over a four kilometer stretch of coast were used to assess spatiotemporal beach and dune evolution at the storm timescale. Consistent with existing field observations from other sandy coastlines, an upward toe retreat was observed for most instances of dune retreat in the Outer Banks. However, these new topographic data indicate that the retreat can proceed steeply downward when the maximum total water level (TWL) defined by the 2% runup exceedance level is not high enough, for long enough, to erode the dune face. Non-linear relationships were found between the dune toe retreat trajectory as well as both the magnitude and duration of TWL above the dune toe, where instances of upward- and downward-directed retreat are best differentiated using the 7% runup exceedance level, rather than the commonly used 2% level. This physically justified non-linear relationship is shown to be consistent with observations from other studies, and could be a more effective parameterization for the retreat trajectory than those currently implemented in wave-impact dune erosion models.