Cities start getting creative in cleaning up runoff

Catalyzed by legal action from enviro groups, the U.S. EPA has started cracking down on an oft-overlooked cause of befouled waterways: polluted runoff. On its journey through urban and suburban streets, rainwater picks up and carries motor oil, antifreeze, pesticides, and other nasties, eventually dumping them in major bodies of water. In the Washington, D.C., area, with the fate of Chesapeake Bay in the balance, local governments have been encouraging — and often requiring — creative approaches to the runoff problem. In Gainesville, Va., a new luxury neighborhood will feature narrower streets, shorter driveways, sunken gardens filled with thirsty plants, and rock-and-shrubbery-filled ditches in place of standard gutters, all to cut down on, soak up, and filter contaminated water before it can reach waterways. In D.C., hundreds of buildings have installed massive subterranean sand vaults to filter their rainwater, and other nearby cities have been experimenting with green roofs and porous parking lots built atop filtering sand. Mind your runoff, folks.