16 Sep 2025

Quality Control for Waterway Networks: Processing Algorithm and GIS Toolbox

Purpose: This Coastal and Hydraulics Engineering technical note (CHETN) documents the development of a US centered Geographic Information System (GIS) representation of navigable waterways for research purposes, including connections with the US Army Corps of Engineers (USACE) National Channel Framework (NCF) reaches, depths, and international connections, and the “Quality Control for Waterway Networks” processing algorithm. The algorithm is an automated method to update a waterway network created by the Coastal and Hydraulics Laboratory (CHL). After a user introduces desired changes to an input line layer representing waterways, the algorithm outputs links and nodes’ shapefiles containing a fully connected network, with geometries and depths aligned with the NCF, and controls for topology and attributes quality. In addition, spatial joins assign attributes to network nodes from other various sources of data. The product of this work is a GIS waterway network, along with a Quality Assurance and Quality Control (QAQC) script incorporated via toolbox within an open-source GIS software to maintain the waterway network updated. The algorithm has the capacity to be adapted to other transportation network needs or GIS software packages.

12 Sep 2025

Arkansas City to Vicksburg Adaptive Hydraulics Model

PURPOSE: The purpose of this study is to develop and validate a 2D, depth-averaged hydrodynamic model of the Mississippi River from Vicksburg, Mississippi, to Arkansas City, Arkansas, to accurately replicate low-flow conditions. The model will be used to support an ongoing effort for the development of a low-water forecast model to aid navigational resilience.

10 Sep 2025

Light Availability Calculator for Identifying Suitable Habitat for Light-Limited Aquatic Vegetation

Purpose: The purpose of this Ecosystem Management and Restoration Research Program Technical Note (EMRRP TN) is to introduce a geospatial Light Availability Calculator, designed to inform suitable habitat selection for light-limited, submerged aquatic vegetation (SAV) species. The need and intended use for the Light Availability Calculator is first described. Then, the scientific and mathematical formulations underpinning the calculator are explained. Finally, recommendations for calculator inputs reflective of various user needs (simple and rapid versus complex and time intensive) are described.

9 Sep 2025

Projecting the Longevity of Coastal Foredunes Under Stochastic Meteorological and Oceanographic Forcing

Abstract: Coastal foredunes serve as critical buffers between the ocean and beach-adjacent infrastructure, yet these features are at increasing risk of destruction from future storms and changes in sea level. Quantifying potential future hazards to dunes is complicated by an inability to forecast the exact sequencing and magnitude of future oceanographic and meteorological forcings. We used a stochastic weather emulator capable of generating time series of wind and wave properties to force a reduced complexity morphologic model to assess potential accretional and erosional dune volume changes over the next century. Inclusion of background beach erosion rates and sea level changes instead drives more frequent net volumetric dune erosion. At decadal scales, volume changes of the dune are shown to be dominated by the magnitude of shoreline change rate in locations rapidly retreating. For stable and mildly eroding shorelines, shoreline changes and changes in the still water level influence timescales of dune destruction. Sets of probabilistic simulations are used to show gradual wind-driven sediment gains can compensate for episodic wave-driven losses over the long term. However, in the case of higher sea levels, more frequent dune collision results in less time for dune recovery between major storms.

9 Sep 2025

Distinct Sandbar Behavior on a Gently Sloping Shoreface Sea-Breeze Dominated Beach

Abstract: Sandbars are common features in sandy nearshore environments that readily migrate in response to changing hydrodynamic conditions and can provide coastal protection by inducing wave breaking and through sediment feeding to the beach. A comprehensive 9-year data set of weekly to bi-weekly surveys of the beach and shallow nearshore, undertaken on an accretive micro-tidal sea-breeze dominated beach along the southeastern coast of Mexico, are presented here that shed new insights into hydrodynamic drivers of inner surf zone sandbar and shoreline dynamics. During spring-summer, short period waves drive offshore sandbar migration. Winter storms generate more energetic swell waves that induce onshore sandbar migration. Seasonal changes of shoreline and inner sandbar position are coupled, with on-shore sandbar migration being synchronous to seasonal shoreline advance, suggesting a gradual feeding of sediment from the bar system onto the beach. Analysis of the data are used to explore the physical drivers of sub-seasonal sandbar evolution at the site. The sandbar dynamics in the study area, showing an opposite behavior to conventional expectation of storm-induced offshore transport, are well correlated to seasonal changes of waves properties. This distinct sandbar behavior might be present at other gently sloping shoreface sea-breeze dominated sandy beaches.

9 Sep 2025

Bayesian Updating of Fatigue Crack Growth Parameters for Failure Prognosis of Miter Gates

Abstract: Navigable waterways play a vital role in efficient transportation of millions of tons of cargo annually. Inland traffic must pass through a lock, which consists of miter gates. Failures and closures of these gates can significantly disrupt waterborne commerce. Miter gates often experience fatigue cracking due to their loading and welded connections. Repairing every crack can lead to excessive miter gate downtime and serious economic impacts. If the rate of crack growth is shown to be sufficiently slow, immediate repairs may be deemed unnecessary, and this downtime can be avoided. Paris’ law is often obtained from laboratory testing with detailed crack measurements of specimens with relatively simple geometry. However, its parameters for an in situ structure will likely deviate from those predicted from physical testing due to variations in loading and materials and a more complicated geometry. To improve Paris’ law parameter prediction, we propose a framework that utilizes convenient vision-based tracking of crack evolution in the laboratory and the field and numerical model estimation of stress intensity factors. This study’s methodology provides an efficient tool for Paris’ law parameter prediction that can be updated as more data become available through vision-based monitoring and provide actionable information.

3 Sep 2025

Hydrodynamics in the Morganza Floodway and Atchafalaya Basin, Report 5: Phase 5

Abstract: The Morganza Floodway and Atchafalaya Basin, located in Louisiana west of the Mississippi River, were evaluated using a 2D Adaptive Hydraulics model. Prior to this study, Phase 1 and 2 model studies showed that the Morganza Floodway may not be able to pass the Project Design Flood discharge of 600,000 cubic feet per second due to levee overtopping. Phase 3 and 4 model studies help to further the understanding of how flood waters propagate throughout the floodway as well examined alternatives to increase the discharge capacity of the floodway. Phase 5 furthered the work completed in Phases 3 and 4 by exploring more alternatives to aid the Morganza Floodway in passing the Project Design Flood.

3 Sep 2025

Hydrodynamics in the Morganza Floodway and Atchafalaya Basin, Report 4: Phase 4

Abstract: The Morganza Floodway and Atchafalaya Basin, located in Louisiana, west of the Mississippi River, were evaluated using a two-dimensional Adaptive Hydraulics model. Prior to this study, Phase 1 and 2 model studies showed that the Morganza Floodway may not be able to pass the Project Design Flood discharge of 600,000 cfs due to levee overtopping. A Phase 3 model study helped to further the understanding of the effects of trees and vegetation on the flow capacity of the floodway. In Phase 4 of this study, changes in elevations through means of excavation as well as the cutting of rights-of-way (ROW) were examined to determine their effects on flow conveyance in the floodway.

2 Sep 2025

Coastal Hazards System–Gulf of Mexico (CHS-GoM)

Abstract: The US Army Corps of Engineers completed the South Atlantic Coastal Study (SACS) to quantify storm surge and wave hazards, expanding the Coastal Hazards System (CHS) to the South Atlantic Division (SAD) domain. The goal of CHS-SACS was to quantify coastal storm hazards for present conditions and future mean sea level fluctuation scenarios to reduce flooding risk and increase resiliency in coastal environments. CHS-SACS was completed for three regions within the SAD domain, and this report focuses on the Gulf of Mexico (CHS-GoM). This study applied the CHS’ Probabilistic Framework with Joint Probability Method Augmented by Metamodeling Prediction (JPM-AMP) to perform a probabilistic coastal hazard analysis (PCHA) of tropical cyclone (TC) and extratropical cyclone (XC) responses, including new atmospheric and hydrodynamic numerical model simulations of synthetic TCs and historical XCs. This report documents the CHS probabilistic framework for the CHS-GoM region by executing the JPM-AMP, and comprising storm climate characterization, storm sampling, storm recurrence rate estimation, marginal distributions, correlation and dependence structures of TC atmospheric-forcing parameters, development of augmented storm suites, and assignment of discrete storm weights to the synthetic TCs. Coastal hazards were quantified for annual exceedance frequencies over the range of 10 yr−1 to 10−4 yr−1.

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.