Background/Objectives

This project focuses on developing workflows and tools to assess multi-hazard flood risks for U.S. Navy Bases along the coast, with the initial application at the Patuxent River Naval Base on the Chesapeake Bay. Coastal communities, including military installations, are exposed to multi-hazard flooding events, exacerbated by expanded coastal infrastructure and varied flood drivers. These risks arise from both tropical cyclones (TCs) and extratropical cyclones (ETCs), leading to storm surges, riverine (fluvial) flooding, and precipitation-driven (pluvial) runoff. The region around the Patuxent River Naval Base is susceptible to these combined flood risks and serves as a pilot study to develop the approach.

Traditional risk management strategies, often focused on TCs, overlook the diverse nature of flooding, especially the impacts of ETCs and the compound effects of fluvial and pluvial factors besides storm surges and waves. This oversight can be important for locations like the Patuxent River Naval Base, where operational schedules and economic considerations are both important considerations that are impacted from flooding. Given the dynamic nature of coastal flood risks, exacerbated by climate change, there is a need for a comprehensive assessment approach. This approach must integrate multi-flood hazard modeling with current engineering practices and research advancements to be successful. The aim of this project is not only to evaluate economic losses but also to consider operational disruptions, improving decision-making tools for strategic planning and mitigation efforts under changing climate conditions at the naval air base.

Approach/Activities

For the coastal flood risk assessment, a synthetic database focusing on both ETCs and TCs. The database was built using storm emulation techniques, parametric wind-pressure and rainfall models, and numerical weather prediction models, forming a set of realistic storm scenarios for current and future climates based on CMIP6 projections. Our methodology uses the generated meteorological conditions to force a high-fidelity hydrodynamic and wave modeling system with fine horizontal resolution extending down to tens of meters for accurate flood driver simulations at various scales.

Results/Lessons Learned

This framework yields data that will be useful for an integrated approach to flood risk modeling, combining both infrastructure and operational vulnerability assessments. We demonstrate that it enables the generation of measurable indicators of flood-related impacts, including economic factors. We will demonstrate that the methodology incorporates risk assessment from both ETCs and TCs in a unified return period analysis. It aligns the frequency of modeled flood events with their potential impacts under various climate scenarios to provide probabilistic risk assessments. Key metrics derived, such as expected annual losses from inundation events, are crucial for stakeholders in making informed decisions for strategic planning and mitigation efforts. The framework's adaptability makes it suitable for diverse coastal environments around the coastlines of the USA.