31 Aug 2022

Coastal Hazards System–Louisiana (CHS-LA)

Abstract: The US Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory (CHL) expanded the Coastal Hazards System (CHS) to quantify storm surge and wave hazards for coastal Louisiana. The CHS Louisiana (CHS-LA) coastal study was sponsored by the Louisiana Coastal Protection and Restoration Authority (CPRA) and the New Orleans District (MVN), US Army Corps of Engineers (USACE) to support Louisiana’s critical coastal infrastructure and to ensure the effectiveness of coastal storm risk management projects. The CHS-LA applied the CHS Probabilistic Coastal Hazard Analysis (PCHA) framework to quantify tropical cyclone (TC) responses, leveraging new atmospheric and hydrodynamic numerical model simulations of synthetic TCs developed explicitly for the Louisiana region. This report focuses on documenting the PCHA conducted for the CHS-LA, including details related to the characterization of storm climate, storm sampling, storm recurrence rate estimation, marginal distributions, correlation and dependence structure of TC atmospheric-forcing parameters, development of augmented storm suites, and assignment of discrete storm weights to the synthetic TCs. As part of CHS-LA, coastal hazards were estimated within the study area for annual exceedance frequencies (AEFs) over the range of 10 yr-1 to 1×10-4 yr-1.

10 May 2021

Risk-Based Prioritization of Operational Condition Assessments: Stakeholder Analysis and Literature Review

Abstract: The US Army Corps of Engineers (USACE) operates, maintains, and manages more than $232 billion worth of the Nation’s water resource infrastructure. Using the Operational Condition Assessment (OCA) system, the USACE allocates limited resources to assess conditions and maintain assets in efforts to minimize risks associated with asset performance degradation. Currently, OCAs are conducted on each component within a facility every 5 years, regardless of the component’s risk contribution. The analysis of risks associated with Flood Risk Management (FRM) facilities, such as dams, includes considering how the facility contributes to its associated FRM watershed system, understanding the consequences of degradation in the facility’s performance, and calculating the likelihood that the facility will perform as expected given the current OCA condition ratings of critical components. This research will develop a scalable methodology to model the probability of failure of components and systems that contribute to the performance of facilities in their respective FRM systems combined with consequences derived from hydrological models of the watershed to develop facility risk scores. This interim report documents the results of the first phase of this effort, stakeholder analysis and literature review, to identify candidate approaches to determine the probability of failure of a facility.