Raising Resilience for Washington, DC with an Integrated Flood Model

Sherwin Zahirieh, PE, ENV SP, Civil Engineer, AECOM

Christine Estes, PE, PMP, CFM, Vice President, AECOM

Washington, DC is uniquely situated at the confluence of two tidal rivers and is vulnerable to flooding from three different sources: riverine, tidal/coastal storm surge, and interior. As emphasized in the DC Department of Energy & Environment’s (DOEE) 2015 Climate Projections & Scenario Development report, all three types of flooding in the District are intensifying as the climate changes. Over recent years, the District has experienced more frequent short intense storms that produce greater rainfall than the city’s stormwater pipe system can handle, causing significant interior flooding. In 2022, the DC Department of Energy & Environment (DOEE) with the AECOM Team started work on designing, building, and providing an Integrated Flood Model (IFM) for the District to better understand interior flooding risk throughout the city, and better predict where this flooding will occur in the future. Over the past year, the IFM has been built and validated, and displays the depth and extent of flooding from the three sources of flooding as a result of various scenarios. The IFM is helping DOEE prioritize where flood mitigation efforts should be directed. The IFM will soon be used to design and test solutions to reduce flood risk throughout the city and will provide District residents a better picture of their flood risk. DOEE is looking for greener, more equitable, and economically sound flood risk reduction solutions. This presentation will review the goals and objectives of the IFM, discuss technical approach and challenges encountered while building the model and identified solutions, share initial results for select model scenarios, describe the system architecture document and designed user interface, and address stakeholder engagement. Finally, we will discuss next steps for the IFM.

Author Bio

Sherwin Zahirieh is a Civil Engineer at AECOM in the Northern Virginia area. He has over 5 years of experience in stormwater engineering design, water quality management, flood hazard modeling, and resiliency planning. He has his B.S. and M.S. in Civil Engineering from George Mason University and is also currently pursuing his PhD part-time there. Outside of his engineering career, he is a marching band instructor and the jazz band director at a local high school. Christine Estes is a Vice President at AECOM in Washington, DC. Christine has over 20 years of experience working in the civil engineering industry, with a focus in water resources. Christine's work has focused on floodplain and stormwater management, watershed planning, and hydrologic, hydraulic and coastal modeling. Prior to joining AECOM, Christine obtained an M.S. in Civil and Environmental Engineering from Virginia Tech and B.S. in Civil Engineering from University of Virginia.