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Watersheds of Santa Clara Valley


Wherever you are, you are in a watershed.

A watershed is the area of land that drains to a common waterway. In Santa Clara County, our creeks and rivers catch rain and runoff from storm drains and carry the water north to San Francisco Bay or south to Monterey Bay. Along the way, some of the water is used to fill reservoirs for drinking water, replenish the underground aquifer and create better habitat for fish and wildlife.

Coyote Watershed


Sixteen major creeks drain this 322 - square - mile area. The county's largest watershed, it extends from the urbanized valley floor upward to the vast natural areas of the Mt. Hamilton range.

Coyote Creek, its main waterway, is the longest creek in the county.

Coyote Watershed is also home to Penitencia Water Treatment Plant, the water district treatment plant serving an area from Milpitas in the north to Aborn Road in the south. The treatment plant is a source of drinking for 270,000 residential and commercial users.

Guadalupe Watershed


This 170 - square - mile area drains the Guadalupe River and its tributaries through downtown San Jose.

Lexington Reservoir, one of the area's best-known landmarks, is located along the western border of this watershed.

Lower Peninsula Watershed


The Lower Peninsula Watershed is a 98-square-mile area whose many small-creek watersheds feed the tidal wetlands along the San Francisco Bay's southwest shorelin.

Its San Francisquito and Stevens creeks in this watershed are among the last remaining viable steelhead trout runs in the county.

Uvas-Llagas Watershed


The Uvas-Llagas Watershed is a 104-square-mile region which is distinguished by its agricultural lands and natural areas.

Part of the larger Pajaro River Watershed, the creeks in this watershed are the only waterways in Santa Clara County that flow southward.

West Valley Watershed


The West Valley Watersheds are an 85-square-mile area of multiple small-creek watersheds.

Characterized by the contrast between its channelized creeks on the valley floor and its more natural streams in the hillsides, this watershed is the county's smallest.


Check out the Watching Our Watersheds (WOW) interactive history map of Santa Clara Valley watersheds

"Watching Our Watersheds" is a project to map the creeks, urban drainage network, watersheds, baylands, and points of interest in Santa Clara Valley.