EPA Approves New Performance Standards for D.C. Stormwater
The U.S. Environmental Protection Agency announced today that it has approved new performance standards for controlling urban stormwater runoff in Washington, D.C. The District’s renewed municipal separate storm sewer system (MS4) permit requires sustainable storm water management techniques including green roofs, tree planting, and retaining rainfall on-site from redevelopment projects.
“This permit includes a number of green performance measures for preventing stormwater, along with the pollutants and trash it carries, from washing into local waterways,” said EPA Regional Administrator Shawn M. Garvin, “Moreover, this builds on efforts the District has already undertaken and is a major step forward in reaching our goals for restoring the Anacostia River and Chesapeake Bay.”
Under the Clean Water Act, urbanized areas like the District are required by federal law to have permits covering their discharges. The permit announced today requires the District to take sustainable steps promoting green infrastructure including:
- Requiring a minimum of 350,000 square feet of green roofs on District properties;
- Planting at least 4,150 trees annually and developing a green landscaping incentives program;
- Retaining for all development projects of at least 5,000 square feet;
- Developing a stormwater retrofit strategy, and implementing retrofits over 18 million square feet of drainage of impervious surfaces;
- Developing consolidated implementation plans for restoring the impaired waterways of the Anacostia and Potomac Rivers, Rock Creek, and the Chesapeake Bay; and
- Preventing more than 103,000 pounds of trash annually from being discharged to the Anacostia River.
The new permit conditions are necessary because impervious surfaces in the District, such as roads, rooftops and parking lots, channel stormwater directly into local streams and rivers. Improperly managed stormwater runoff from the District damages streams, causes significant erosion, and carries excessive pollutants like nitrogen, phosphorus, sediment, toxic metals, and solvents downstream and into the Chesapeake Bay. This permit aids the District in meeting its Chesapeake Bay pollution reduction targets and its Watershed Implementation Plan.
In finalizing the D.C. MS4 permit, EPA prepared responses to 21 individual comment letters received during the 45-day public comment period which closed on June 4, 2010, as well as approximately 50 separate form letters from area residents.
To view the permit, fact sheet and response to comments online visit: http://www.epa.gov/reg3wapd/npdes/dcpermits.htm