Created as a special district in 1949 by the California Legislature to provide flood protection and water supply services, legislation enacted in 1995 added treatment and waste disposal.  The Water Agency serves Cotati, Marin Municipal Water District, North Marin Water District, City of Petaluma, City of Rohnert Park, City of Santa Rosa, City of Sonoma, Valley of the Moon Water District, and the Town of Windsor.

The Sonoma County Water Agency believes in the idea of supporting environmental stewardship and sustainability to improve quality of life, providing an array of services including naturally-filtered drinking water, flood protection services, recreational opportunities and wastewater treatment. More information at www.scwa.ca.gov