HEC-RAS 2D MODELING: REVOLUTIONIZING THE PRACTICE OF FLOOD MAPPING AND RISK ASSESSMENT

摘要

Following severe flooding in 2011 in Saskatchewan, Manitoba, and Quebec, the Government of Canada established the National Disaster Mitigation Program (NDMP) in April 2015 in recognition of increasing flood disaster risk and cost. The Government's commitment to build safer and more resilient communities includes investing$200 million over five years in four components of emergency management: Risk Assessments, Flood Mapping, Mitigation Planning, and Investments in Non-Structural and Small Scale Structural Mitigation Projects. Historically, resource limitations allowed only basic methodologies and tools to be used for identifying infrastructure vulnerabilities, flood risk, and mitigation strategies. However recent advancements by the Hydrologic Engineering Center (HEC) for the U.S. Army Corps of Engineers has updated the River Analysis System (HECRAS Version 5.0.1, April 2016 Release) to perform not only one-dimensional, but two-dimensional (2D) and combined one- and two-dimensional (1D/2D) hydrodynamic modeling. The new capabilities of HEC-RAS allows users to increase detail and maintain efficiencies of existing models, while increasing the value to emergency management planning and providing the foundation for informed mitigation investments. This presentation will focus on the recent advancements in HEC-RAS 2D modeling that can be applied to dam and levee safety, risk assessment, and emergency flood preparedness. Demonstrations will include modeling capabilities for flow depth, velocities, inundation timing, and flood hazard characterization.