About Our Water System
Our Distribution System
Chartered in 1912, Marin Water is California’s first and the oldest municipal water district. We are proud to provide locally sourced water to more than 191,000 customers in central and southern Marin County.
About 75 percent of our water supply originates from rainfall on 22,000 acres of our protected Mt. Tamalpais watershed and in the grassy hills of west Marin. Rainfall from the watershed flows into the District’s seven reservoirs. The water is treated at our treatment plants and then travels through our extensive distribution system—including 908 miles of pipes, 130 storage tanks and 97 pump stations—before making its way to your home or business. The district also supplements its water supply with water from the Sonoma County Water Agency (SCWA), which comes from the Russian River system in Sonoma County. The Russian River water supply originates from rainfall that flows into Lake Sonoma and Lake Mendocino, and it is naturally filtered through 80 feet of sand beds adjacent to the river. It then goes through a treatment process and is blended with the District’s reservoir water within its distribution system.
Our Water Service Operation at a Glance
Clean water is more than turning on the tap. Get to know the massive water system that delivers for you.
Acres of Watershed
Miles of Pipeline
Water Quality Tests per Year
Storage & Treatment
Learn more about our water supply storage