New standards for Washington, D.C., redevelopment will reduce polluted runoff to Anacostia, Potomac rivers and Chesapeake Bay

The U.S. Environmental Protection Agency has approved new standards to control polluted stormwater runoff from roads, buildings and other developed areas in Washington, D.C.

The District’s renewed municipal separate storm sewer system (MS4) permit requires that redevelopment projects in the city install runoff-reducing practices to slow the flow of polluted stormwater to the Anacostia and Potomac rivers and the Chesapeake Bay.

The required practices include:

• Requiring a minimum of 350,000 square feet of green roofs on properties across the city
• Planting at least 4,150 trees each year and developing a green landscaping incentives program
• Retaining 1.2 inches of stormwater on site from a 24-hour storm 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 areas
• Developing consolidated implementation plans for restoring the Anacostia and Potomac rivers, Rock Creek and the Chesapeake Bay
• Preventing more than 103,000 pounds of trash from being discharged to the Anacostia River each year

Roads, rooftops, parking lots and other hard surfaces channel stormwater directly into local rivers and streams, carrying pollution and eroding streambanks. The renewed permit will help the District in meeting its Bay pollution reduction goals and Watershed Implementation Plan (WIP).

Visit the EPA’s website to learn more about the new stormwater permit and standards.