Runoff from streets and roads is the source of a large amount of “non-point” source pollution — the “urban slobber” that leads to most new water pollution in the United States today.

Among the pollutants are gas and oil, heavy metals from tires and brakes, and soap from washing cars or equipment.

As the projects below show, there are many ways this pollution can be kept out of waterways, and flash-flood-like storm flows can be reduced. Streets can be curbless or curbs can be cut. Runoff can flow to swales, basins, or simply overland.
Bioswale in "bulb-out" shortening pedestrian crossing
Green Street projects, Albany and Emeryville

Clayton: Pine Hollow single-family homes
Swale & bike trail at Eleanor Murray Fallon School
Dublin: Big swales and pond

El Cerrito Sidewalk Rain Gardens
Rain Garden and Street Trees that filer runoff, Doyle Hollis Park
Emeryville: Doyle-Hollis Park

Livermore: Canziani Park and Charlotte Ave.

Livermore: Charlotte Avenue area

Pleasant Hill: Hidden Creek

Pleasanton: Single-FamilyHomes

Narrow streets, limited parking, and swales on Paulson Lane, Walnut Creek
Walnut Creek: Paulson Lane urban infill