Group Suggests City Adopt 'Low Impact Development' Policy to Mitigate Pollution
WASHINGTON (July 17, 2002) - The Water and Sewer Authority's (WASA) plan to clean up polluted runoff and raw sewage discharges relies too heavily on an anachronistic and costly centralized underground system of storage tunnels, according to a study released today by NRDC (Natural Resources Defense Council). The report recommended that WASA adopt more decentralized approaches that would redirect rain into the ground instead of into local waterways.
"The District is using a 19th century approach to stormwater," said Jim Woodworth, an urban water specialist at NRDC's Clean Water Project and primary author of the report. "It relies on archaic engineering that funnels rain down gutters and curbs into sewer pipes instead of back into the ground. We wind up with bacteria-laced rivers, dead fish, and sick swimmers."
The report, Out of the Gutter: Reducing Polluted Runoff in the District of Columbia, found that WASA's approach would not significantly improve the health of the three main waterways in the District: Rock Creek, the Potomac, and especially the Anacostia. "The Anacostia is in intensive care," Woodworth said, "and WASA's plan won't save it."
"Out of the Gutter" was funded in part by the District, which asked NRDC to review city codes, recommend new policies to address the problem, and identify impediments to implementing a responsible plan. The report concluded that the major problem in the District -- as in most urban areas -- is that there are too many impervious surfaces, such as roads, parking lots and roofs, which cannot soak up rain. Rain runs off these surfaces, collecting pollutants, and flows quickly into storm drains, which empty directly into our waterways.
The best way to deal with this runoff problem, according to the report, is a new approach called "low impact development." Low impact development relies on decentralized techniques, such as "green" roofs, which use soil and vegetation to soak up rain and prevent it from washing directly into waterways. There are two notable low impact demonstration projects in the District: the Washington Navy Yard, which has installed permeable pavement and rain barrels, and the Earth Conservation Corps building on Half Street SW, which has a green roof. There also are numerous examples throughout suburban Maryland, and just across the Potomac River in Virginia there are plans to build a green roof as part of the Pentagon renovation.
Chicago, Milwaukee, Philadelphia and Portland, Oregon, are beginning to use these low impact development techniques. Some companies are embracing low impact development, too. Ford Motor Co., for example, is installing a green roof on its 480,000-square-foot River Rouge Plant in Dearborn, Michigan. It will be the largest green roof in the world.
In contrast, WASA's $1.265-billion control plan for combined sewer overflows -- which will be released this week -- relies predominantly on a centralized underground system of storage tunnels and earmarks only $3 million for low impact development projects. NRDC says WASA should dedicate more funding to low impact development to complement its expensive, subterranean tunnel system.
The NRDC report calls on the District government and WASA to:
- Coordinate among city agencies to implement low-impact development techniques on city-owned property and establish a clearinghouse to disseminate information to the public on these techniques.
- Restructure the city's flat stormwater fee to take into account the amount of impervious surface areas on a property and the amount of stormwater runoff it causes. Ratepayers whose property generates more runoff should pay higher fees. Property owners who institute low-impact development techniques to mitigate runoff would be rewarded with lower fees.
- Protect environmentally sensitive lands -- including steep slopes, riparian and riverfront areas -- through planning, zoning and development codes.
- Restore the urban forest by supporting a strong urban forest bill, revising planting standards and funding replanting efforts. The City Council is currently considering the forest bill.
- Encourage water conservation and water reuse techniques, and policies for building design and property maintenance.
The Natural Resources Defense Council is a national, non-profit organization of scientists, lawyers and environmental specialists dedicated to protecting public health and the environment. Founded in 1970, NRDC has more than 500,000 members nationwide, served from offices in New York, Washington, Los Angeles and San Francisco.