Russian River

The Russian River, a southward-flowing river, drains 1485sqmi of Sonoma and Mendocino counties in Northern California. With an annual average discharge of approximately 1600000acre.ft, it is the second-largest river (after the Sacramento River) flowing through the nine-county Greater San Francisco Bay Area, with a mainstem 110 miles (177 km.) long.CourseThe Russian River springs from the Laughlin Range about 5mi east of Willits in Mendocino County. It flows generally southward to Redwood Valley, then past Calpella, where it is bordered by U.S. Route 101, to join the East Fork Russian River just below Lake Mendocino.From there the Russian River flows south, past Ukiah and Hopland, and crosses into Sonoma County just north of Cloverdale. Closely paralleled by U.S. Route 101, it descends into the Alexander Valley, where it is joined by Big Sulphur Creek. It flows south past Cloverdale, Asti, and Geyserville.