BART rain gardens work

BART says the rain gardens it has added at stations are built to catch stormwater before it reaches the Bay, using soil and plants to filter pollution. (bart.gov) In an Earth Week post published April 21, 2026, Bay Area Rapid Transit said it has installed bioretention areas — also called rain gardens — at stations including Richmond, Warm Springs, Lafayette, El Cerrito del Norte, Concord, Millbrae, Balboa Park, San Bruno and Antioch. (bart.gov) BART said those landscaped basins are designed to slow runoff, hold it briefly and strain out debris, hydrocarbons and heavy metals before water enters creeks or the San Francisco Bay. The U.S. Environmental Protection Agency describes bioretention the same way: shallow planted areas that collect runoff from hard surfaces and filter it through engineered soil. (bart.gov) (epa.gov) Stormwater is rain that runs off roofs, streets, sidewalks and parking lots instead of soaking into the ground. In urban areas, that water often flows into storm drains without treatment, carrying oil, metals, trash and bacteria with it. (seattle.gov) (kingcounty.gov) That is why utilities in Washington keep pushing small cleanup steps at home. King County says polluted runoff reaches Puget Sound through gutters and storm drains, and Seattle Public Utilities asks residents to keep drains clear of leaves and trash to cut both pollution and localized flooding. (kingcounty.gov) (seattle.gov) Pet waste is part of the same problem. The Environmental Protection Agency says stormwater can pick up animal waste left on the ground and carry it through storm sewers into nearby waters, while King County says pet waste and bacteria in runoff can harm shellfish beaches, salmon and orcas. (epa.gov) (kingcounty.gov) Washington state officials frame Puget Sound as a runoff problem as much as a wastewater problem. The Department of Ecology says polluted surface runoff is the most common pathway for toxic chemicals to reach Puget Sound, and older Ecology summaries say surface runoff carries oil, petroleum products and metals into the estuary. (ecology.wa.gov) (apps.ecology.wa.gov) Seattle’s public warnings about storm drains are blunt: what goes into a curbside grate can end up in Lake Washington, the Duwamish River or Puget Sound. The city’s drain-stenciling program uses the message “Dump No Waste / Drains to Puget Sound” to make that link visible on the street. (seattle.gov) The thread connecting BART’s planters and Puget Sound drain campaigns is simple infrastructure math: capture polluted water where it falls, or it moves downstream untreated. Agencies on both coasts are betting that planted basins, cleaner gutters and fewer spills can keep at least some of that pollution out of the water in the first place. (bart.gov) (ecology.wa.gov)