FEDERAL TRIANGLE Flood Risk Management presented by Anthony Mondy - PowerPoint PPT Presentation

U.S. General Services Administration FEDERAL TRIANGLE Flood Risk Management presented by Anthony Mondy

Time Interval Duration Precipitation Return Frequency 9:00 PM – 11:00 PM 2 hours 3.34 inches 50-year 9:00 PM – 2:00 AM 6 hours 5.91 inches 200-year June 25, 2006 Extreme Storm: Interior Drainage Flooding Annual Return Interval: Design Storm 15 th Commerce 14 th IRS 10 th EPA West Mellon Auditorium EPA East 12 th a

Federal Triangle Flood Damage, June 2006

Federal Triangle Flood Damage, June 2006 Abandoned Duct Bank Theater Basement

Design Storm Contours Greeley & Hansen: FT Storm Water Drainage Study (Modified)

Base Flood Elevations Interior Drainage Design Storm Contours GSA has recently completed an incremental risk assessment of each of the impacted buildings and identified cost effective flood protection measures. 2

Storm Water Pathway Top of Moat Wall Elevations 15 th Commerce 14 th EPA West Mellon Auditorium EPA East 12 th IRS 10 th 10.1 9.6 500 Year Storm: 8.6 ft. 200 Year Storm: 8.1 ft. 100 Year Storm: 7.7 ft. 7.45 50 Year Storm 7.0 ft.

Federal Triangle Critical Pathways, June 2006 IRS OPO EPA

IRS Building: Evaluate Utilizing Passive Floodgate at the Moats Top of Moat Elevation 8.9 > 500 Year Storm Top of Moat Elevation 8.0 < 200 Year Storm Top of Moat Elevation 7.9 < 200 Year Storm Floodgate TM

Electrical Equipment Enclosure Vegetative Roofing Rain Gardens Flood Doors New Steam Tunnel 2 Chiller Room Flood Door

Federal Office Building: New Flex Walls at Garage Ramps Flex-Wall Installed inside of doorway to minimize impact to historic fabric. Critical Pathway for Flood Water Infiltration “Historic Building” PEPCO Duct Bank Storm Main Failure