3 Feb 2026

Sensitivity and Impact of Atmospheric Forcings on Hurricane Wind Wave Modeling in the Gulf of Mexico Using Nested WAVEWATCH III

Abstract: Precise estimation of hurricane wind-induced waves is critical to enhance the accuracy of predicting coastal flooding events in real-time besides helping in the design of sustainable coastal/offshore structures. In this study, we aim to investigate the importance of atmospheric forcings and their impact on wind wave modeling for extreme hurricane conditions in the Gulf of Mexico (GOM) basin. Hurricanes Michael (2018) and Ida (2021) were chosen to be modeled as they were among the two most severe storm events that attained category 5 and category 4 status, respectively, during landfall in the GOM basin. A multi-grid nested modeling approach was implemented in WAVEWATCH III with three different wind forcings: ECMWF’s ERA5, NOAA’s High-Resolution Rapid Refresh (HRRR: v3 and v4) and ECMWF’s Operational High-Resolution Forecast Model (ECMWF) to model both hurricanes. The results generated through model simulations of various cases were compared with the field observations obtained at NDBC stations. One of the findings suggests that the ERA5 based wind model substantially underestimates the peak winds of both the hurricanes by 50–60 %, thereby resulting in significant underestimation of the wave heights by 40 %. Although the ECMWF model could not capture the maximum winds generated by Michael and Ida, it still gave better results than the ERA5 and HRRR (v3). The updated version (v4) of HRRR performed better than both ERA5 and ECMWF wind models in predicting the peak wind speeds and wind field distribution of Hurricane Ida in all the quadrants.

30 Jan 2026

Estimating Component Probability of Failure at USACE Civil Works Facilities for Asset Management

Abstract: Infrastructure components are the building blocks of US Army Corps of Engineers (USACE) facilities such as navigation locks and dams. Estimates of component probability of failure are needed to support risk-informed decisions about managing and maintaining these systems and their components. At Inland Navigation (INAV) facilities, the models and methods currently in use are based on an expert elicitation. There is a need for more objective estimates of component probability of failure derived from data using statistical models and methods. This report demonstrates these models and methods and describes what kinds of data would be needed to put them into practice. The major impediment to putting these models and methods into practice is a lack of data on the age, performance, and other characteristics of in-service components. It will take time to develop these data. In the meantime, this report describes how these statistical methods and models can be adapted for use with operational condition assessment (OCA) ratings, which USACE maintains in an existing database at the enterprise scale. Finally, this report describes an analytical approach to criticality assessment, which is a systematic process for identifying which components, if failed, would lead to significant operational disruptions.

30 Jan 2026

Linear Propagation of Tsunami and Acoustic–Gravity Waves on a Sphere: Geometrical Focusing and Defocusing

Abstract: This study investigates the propagation of tsunami and acoustic–gravity waves at oceanic scales, accounting for the Earth’s curvature within a linear, potential flow framework. While local, near-field analyses often neglect Earth’s curvature and employ Cartesian or cylindrical coordinate systems, this work utilises spherical coordinates to examine wave behaviour over large distances. The analysis reveals that wave amplitudes experience a defocusing effect as they travel from the source (e.g., the Pole) toward the equator, followed by a focusing effect as they approach the antipodal point beyond the equator. A qualitative comparison is made with the 2022 Hunga Tonga–Hunga Ha’apai volcanic eruption in the South Pacific. The study models surface-gravity (tsunami) waves propagating through a compressible water layer, as well as atmospheric acoustic–gravity waves propagating through the air. The entire analysis is carried out within the framework of linear theory.

29 Jan 2026

A Monolithically Coupled Surface Water and Groundwater Finite Element Model with Fully Implicit Time Stepping Using Adaptive Hydraulics (AdH) v5.0 (KraRE: 21428 (ken)

Abstract: Simulation of surface water and groundwater interaction is becoming increasingly important for the US Army Corps of Engineer Civil Works and Military Missions. This report details the formulation of a monolithic, coupled approach that combines the Richards equation for variably saturated groundwater flow and a diffusive wave approximation for overland flow. The model is implemented with USACE’s Adaptive Hydraulics (AdH) computational framework and is evaluated for several community benchmark problems. The results indicate that the AdH model is stable with performance similar to existing, well-established codes for surface water and groundwater interaction.

21 Jan 2026

Development of Tidal and Surge Forcing in Boussinesq Wave Model FUNWAVE-TVD

PURPOSE: This Coastal and Hydraulics Engineering Technical Note (CHETN) documents the development of the tidal and surge-forcing module in the Boussinesq wave model FUNWAVE–Total Variation Diminishing (TVD) for wind-wave simulations, subjected to large-scale boundary forcing conditions. In a series of recent projects undertaken by the Coastal Hydraulics Laboratory (CHL) of the US Army Engineer Research and Development Center (ERDC), there was a need to model wind waves under time-varying boundary conditions due to tides, storm surges, or strong background flows. The implications on wave runup and overtopping (flooding) around inlets, due to the interaction of tide or surge-driven flows and waves (wave-current interactions), make the need for the development of surge and tide forcing vital to modeling waves with a Boussinesq-type model like FUNWAVE-TVD. Furthermore, strong velocity flows (currents) are not only responsible for depth-limited wave transformation and breaking at inlets but also directly influence sediment transport. Most phase-resolving wave models cannot facilitate these kinds of simulations because the wavemaker cannot generate the phase-resolving wave conditions and low-frequency motions (e.g., tides) at the same time. For example, in FUNWAVE-TVD, the combination of an internal wavemaker and a sponge layer is used to generate wind waves in the shoreward direction while absorbing waves with the sponge layer in the seaward direction behind the wavemaker. However, this type of combined system of wave generation and absorption cannot readily incorporate the external low-frequency forcing into wave generation.

13 Jan 2026

Wave Information Study ERA5 Wind-Field Evaluation

Abstract: The Wave Information Study (WIS) provides continuous wave hindcasts along US coastlines, including the Great Lakes and US Territories. As wave modeling and wind-field technologies have advanced, WIS is now positioned to transition to the new long-term archived hindcast wind fields available from ERA5, the fifth-generation global atmospheric reanalysis from the European Centre for Medium-Range Weather Forecasts. Before adopting ERA5 operationally within the WIS hindcast, formal testing compared ERA5 wind-forced hindcasts to the existing WIS hindcasts using Nation Center for Atmospheric Research Reanalysis 1 (NCAR-R1) winds. Results were validated against collocated and concurrent point-source and altimeter-based wave measurements from 2015 to 2018. ERA5 showed a 53% improvement in significant wave-height bias in the Atlantic and 76%–77% improvements in the Pacific. While improvements in average wave period were less consistent, ERA5 still showed better correlation across all domains. Hawaii showed modest improvements, except for bias. ERA5 also outperformed NCAR-R1 in mean wave direction at peak frequency, with bias reductions of 5%–72%, most notably in Hawaii, where wave modeling is typically challenging. Overall, it was concluded that the ERA5 forced WIS estimates were more accurate than the NCAR forced WIS estimates, supporting the operational transition of WIS to ERA5.

13 Jan 2026

Major Freight Corridors in the US: Mapping of Commodity Flows on Waterborne, Rail, and Truck Networks

Abstract: Within the context of complex, interconnected, multimodal transportation, the US Army Corps of Engineers (USACE) provides safe, reliable, efficient, effective, and environmentally sustainable waterborne transportation systems for the movement of commerce, national security needs, and recreation. Understanding the role of waterways within the multimodal transportation system would allow for comprehensive resource allocation, including dredging prioritization. In 2022, approximately 19,810 million tons of goods were transported within, to, and from the US, with truck being the dominant mode for the domestic portion of the trip (64 percent). Relatively recent legislation calls for a multimodal representation of freight, one that facilitates transportation planning and asset management. However, traditional data collection and analysis has focused on single modes, preventing nationwide, multimodal representations of commodity flows. This report presents major commodity corridors within, to, and from the US by combining diverse sources and homogenizing data dimensions. The resulting information and commodity-specific maps help to contextualize waterborne navigation’s role within the broader multimodal transportation system. A key finding from the study indicates that the mouth of the Mississippi River in Louisiana carried in 2019 more volume of freight annually than any other waterway, railroad, or highway segment in the US.

9 Jan 2026

Design of River Training Structures Using Isogeomorphic Constraints

Abstract: Prepared for the Mississippi River Geomorphology and Potamology program of the United States Army Corps of Engineers (USACE), through the Coastal and Hydraulics Laboratory (CHL), this report introduces the concept of river control structure design using isogeomorphic constraints. The report defines isogeomorphic design methodology and demonstrates the application of the methodology using both analytic and numerical examples. The examples investigated herein are idealized, and application to real-world conditions (such as a dike-field) would be far more complex than what is demonstrated herein. This report merely serves as an introduction to a novel design paradigm that future studies can further investigate and refine with the ultimate objective of developing improved design guidance for USACE.

10 Dec 2025

A Qualitative Comparison Review Between Commonly Used Boussinesq Models

Abstract: The purpose of this Coastal and Hydraulics Engineering Technical Note (CHETN) is to summarize the Boussinesq models FUNWAVE, Coulwave, and Celeris. This CHETN outlines the governing equations and numerical schemes for each model and presents the order of their error terms. A qualitative comparison was completed between the fully nonlinear models, FUNWAVE and Coulwave, and the weakly nonlinear model, Celeris. Results from this comparison demonstrate capabilities for each model by comparing previously published benchmark validation cases. The discussion section highlights additional areas of research and report recommendations.

10 Dec 2025

Evaluation of Vegetated Shoreline Capacity Using CSHORE-VEG

Abstract: A versatile vegetation module has been implemented into the Cross-Shore model (CSHORE) to evaluate the capacity of coastal and marine wetlands with respect to wave-height attenuation and wave-runup reduction. This extended model, Cross-Shore-Vegetation (CSHORE-VEG), is capable of simulating the effects of rigid and flexible vegetation with spatially varying biomechanical properties. To accurately estimate the vegetation-induced energy dissipation rate, a drag coefficient formula that is independent of the vegetation flexibility was developed based on field data collected in salt marshes in Terrebonne Bay, Louisiana, during a tropical storm. This universal drag coefficient formula along with other existing drag coefficient formulas have been implemented into CSHORE-VEG to meet different needs. CSHORE-VEG has been validated against four independent datasets involving different vegetation properties for wave attenuation and mean water level change. After achieving good agreement in model-data comparisons, CSHORE-VEG was employed to quantify the capacity of two representative salt marshes composed of Spartina alterniflora and Elymus athericus for wave attenuation. As a result, two ineffective vegetated shoreline scenarios were identified. Furthermore, a procedure for determining the percentage of broken vegetation stems and modeling the corresponding wave-height reduction was applied to evaluate the wave-height reduction under realistic field conditions.