The US Army Corps of Engineers, Galveston District, is executing the Coastal Texas Protection and Restoration Feasibility Study coastal storm risk management (CSRM) project for the region. The project is currently in the feasibility phase. The primary goal is to develop CSRM measures that maximize national net economic development benefits. This report documents the coastal storm water level and wave hazard, including sea level rise, for a variety of flood risk management alternatives. Four beach restoration alternatives for Galveston Island and Bolivar peninsula were evaluated. Suites of synthetic tropical and historical non-tropical storms were developed and modeled. The CSTORM coupled surge-and-wave modeling system was used to accurately characterize storm circulation, water level, and wave hazards using new model meshes developed from high-resolution land and sub-aqueous surveys for with- and without-project scenarios. Beach morphology stochastic response was modeled with a Monte Carlo life-cycle simulation approach using the CSHORE morphological evolution numerical model embedded in the StormSim stochastic modeling system. Morphological and hydrodynamic response were primarily characterized with probability distributions of the number of rehabilitations and overflow.

The US Army Corps of Engineers, Galveston District, is executing the Sabine Pass to Galveston Bay Coastal Storm Risk Management (CSRM) project for Brazoria, Jefferson, and Orange Counties regions. The project is currently in the Pre-construction, Engineering, and Design phase. This report documents coastal storm water level and wave hazards for the Port Arthur CSRM structures. Coastal storm water level (SWL) and wave loading and overtopping are quantified using high-fidelity hydrodynamic modeling and stochastic simulations. The CSTORM coupled water level and wave modeling system simulated 195 synthetic tropical storms on three relative sea level change scenarios for with- and without-project meshes. Annual exceedance probability (AEP) mean values were reported for the range of 0.2 to 0.001 for peak SWL and wave height (Hm0) along with associated confidence limits. Wave period and mean wave direction associated with Hm0 were also computed. A response-based stochastic simulation approach is applied to compute AEP runup and overtopping for levees and overtopping, nappe geometry, and combined hydrostatic and hydrodynamic fluid pressures for floodwalls. CSRM structure crest design elevations are defined based on overtopping rates corresponding to incipient damage. Survivability and resilience are evaluated. A system-wide hazard level assessment was conducted to establish final recommended system-wide CSRM structure elevations.

Large scale flood risk computation has enjoyed a metamorphosis since Hurricane Katrina. Improved characterization of risk is the result of improved computational capabilities due to super computer capacity combined with coupled regional hydrodynamic models, improved local hydrodynamic models, improved joint probability models, inclusion of the most important uncertainties, metamodels and increased computational capacity for stochastic simulation. Improvements in our understanding of, and the ability to model, the coupled hydrodynamics of surge and waves has been well documented as has been improvements in the joint probability method with optimal sampling (JPM-OS) for synthesizing synthetic tropical cyclones (TC) that correctly span the practical hazard probability space. However, maintaining the coupled physics and multivariate probability integrity through the entire flood risk computation while incorporating epistemic uncertainty has had relatively little attention. This paper addresses this latter topic within the context of the Sabine Pass to Galveston Bay, TX Pre-Construction, Engineering and Design, Hurricane Coastal Storm Surge and Wave Hazard Assessment.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/qYFTO6l7UME

The Environmental Monitoring and Operation Guidance System (EMOGS) tool was developed in 1989 to provide a real-time risk analysis for underkeel clearance for the Ohio class submarine while in transit to the Naval Submarine Base at Kings Bay, Georgia. The program computes expected submarine response for input water level, depth, speed, wave, and other input conditions using shallow-water motion transfer functions generated by the strip theory tool, Large Amplitude Motion Program (LAMP). The integration of the new Columbia class submarine into EMOGS required that new transfer functions be developed using LAMP. The LAMP results are to be validated using measured motions from physical model laboratory testing. This report summarizes a laboratory study of the Columbia class submarine response in shallow-water waves. The study was conducted at the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, and was done in direct support of the Naval Surface Warfare Center, Carderock Division. These seakeeping tests were performed in a shallow basin with a multidirectional wave generator, with measured still water vessel motions and measured vessel motion in regular and irregular waves of varying height, period, and direction. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

The US Army Corps of Engineers, Galveston District, is executing the Sabine Pass to Galveston Bay Coastal Storm Risk Management (CSRM) project for Brazoria, Jefferson, and Orange Counties regions. The project is currently in the Pre-construction, Engineering, and Design phase. This report documents coastal storm water level (SWL) and wave hazards for the Freeport CSRM structures. Coastal SWL and wave loading and overtopping are quantified using high-fidelity hydrodynamic modeling and stochastic simulations. The CSTORM coupled water level and wave modeling system simulated 195 synthetic tropical storms on three relative sea level change scenarios for with- and without-project meshes. Annual exceedance probability (AEP) mean values were reported for the range of 0.2 to 0.001 for peak SWL and wave height (Hm0) along with associated confidence limits. Wave period and mean wave direction associated with Hm0 were also computed. A response-based stochastic simulation approach is applied to compute AEP values for overtopping for levees and overtopping, nappe geometry and combined hydrostatic and hydrodynamic fluid pressures for floodwalls. CSRM crest design elevations are defined based on overtopping rates corresponding to incipient damage. Survivability and resilience are evaluated. A system-wide hazard level assessment was conducted to establish final recommended system-wide elevations.