The Petaluma Watershed is located in southern Sonoma County and northeastern Marin County, California, with the City of Petaluma near its center. The Petaluma River is 19 miles long and actually a tidal estuary, but was named a river by an Act of Congress in 1959. The tidal influence extends from San Pablo Bay to just upstream of the Lynch Creek/Petaluma River confluence.

146 square miles
19 miles long and 13 miles wide
Mountainous or hilly upland area, 56%
Valley area, 33%
Salt marsh area, 11% (largest intact tidal estuary in California, ~5,000 acres)
Provides habitat for many federally listed endangered and threatened species Such as the Clapper Rail, the California Black Rail, the California Red-Legged Frog, and the Salt Marsh Harvest Mouse
12 of 25 species of marine, estuarine, and freshwater fish are native to California

For more information: Petaluma Watershed Enhancement Plan, Sonoma RCD and State Water Resources Control Board, 1999

Russian River Watershed

Colgan Creek Subwatershed

Petaluma River Watershed

Russian River Watershed

Colgan Creek Subwatershed

Petaluma River Watershed

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