BY BRADFORD MCKEE
Gray infrastructure has given way to green to prevent sewer overflows into Washington, D.C.’s waters.
FROM “THE RIVER BENEATH THE RIVER,” IN THE NOVEMBER 2018 ISSUE OF LANDSCAPE ARCHITECTURE MAGAZINE.
Green infrastructure is now an important part of the Clean Rivers Project. The colossal Anacostia River tunnel remains a fixture in the effort on the east side of the city to hold and carry stormwater to DC Water’s Blue Plains Advanced Wastewater Treatment Plant. But to the west, the introduction of green infrastructure is allowing the elimination of one smaller tunnel for a combined sewer network above Rock Creek, which drains into the Potomac River, and the scaling back of another large tunnel along the Potomac itself.
The notion of complementing gray infrastructure with green was a priority of George Hawkins when he became general manager of DC Water in 2009. It was not an easy sell. Clean-water advocates were skeptical of green infrastructure’s performance capability and also feared delays in achieving the goals of the Clean Rivers Project—to end 96 percent of the District of Columbia’s combined sewer overflows. Hawkins was able to make a case for the efficacy of green infrastructure and also to show that significant improvements to water quality would occur well before the tunnels’ projected completion.
The Clean Rivers program is deploying a mix of bioretention, porous pavements, rain barrels, and downspout disconnection from combined sewers. In the Rock Creek sewershed, enough green infrastructure is planned to manage (more…)
