West Marin Waters

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The West Marin region is a part of a robust watershed, but its defining feature is the vast Pacific Ocean, which surrounds its shores. (more facts upwelling, currents)

For thousands of years humans have depended on these rich waters for food, clothing, and transport. Today, these waters still provide those elements, but have also have become places for the masses to recreate and relax. With climate change, pollution, shifting political priorities, tourism and other factors effecting our environment, EAC remains constant in reviewing and researching issues important to our community. 

Located just an hour from San Francisco, our mission-based work focuses on environmental issues facing the coastal communities of West Marin, the largest rural region of Marin County, California. The area generally extends from Dillion Beach to the north, south to Muir Beach, and west of Nicasio and the San Geronimo Valley, out to the Pacific Ocean. The area includes several unincorporated coastal communities (BolinasDillion BeachInvernessMarshallMuir BeachOlemaPoint Reyes StationStinson Beach, and Tomales), and is home to approximately 16,000 people, or about 6.5% of the population of Marin County, and receives over 2+ million visitors a year in search of respite, relaxation, and recreation. 

Our work is focused on bringing people, science and policy together, to solve some of these threats and champion innovative solutions. For over forty years we’ve worked on various projects to protect vital ecosystems, defend critical legislation, enforce accountability of leaders and legislators and rally our community to become stewards of their backyard. Because a healthy watershed and ocean means a healthy planet.

West Marin Unique Water Features

Discover some of the unique water features of the area, and agencies we partner with to ensure our water resources are protected and conserved for years to come below. Also be sure to check our EAC current water programs and past successes below. 

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Fresh Water

The Marin Municipal Water District manages a complex distribution system of reservoirs, tanks, pumps and pipelines to deliver water to the area. About 75% of Marin's drinking water comes from rainwater captured on 21,500 acres of protected watershed in seven reservoirs on Mt. Tamalpais and in West Marin. The rest is imported from the Russian River in Sonoma County. Learn more

Salt & Brackish Waters

Bolinas Lagoon managed by Marin County Parks is an international Ramsar site, or wetland of international importance located in the southern part of western Marin, and along the Pacific Flyway providing important wintering area for scores of birds and habitat for breeding colonies of birds and marine life. The endangered steelhead and coho salmon move through the lagoon on their way to spawn in streams within the lagoon’s watershed. Together these estuaries provide a wetland complex of exceedingly rich ecological value in western Marin


Cordell Bank National Marine Sanctuary, located offshore of West Marin's Point Reyes National Seashore is one of the many gems providing comprehensive and coordinated conservation and management of the marine resources on the continental shelf and slope, from about 7 to 51 miles (6 to 44 nautical miles) west of Bodega Head, California and about 52 miles (45 nautical miles) west-northwest of San Francisco. The total area of the sanctuary is 1286 square miles. It is an extremely productive marine area off the west coast of United States in northern California, just north of the Gulf of the Farallones. In total, the sanctuary protects an area of 1286 square miles off the northern and central California coast. Learn more about its unique geology, marine life, and history.

Greater Farallones National Marine Sanctuary surrounds West Marin's seashore, and is a complex region with high biological diversity; nationally significant wildlife breeding and foraging areas; significant commercial and recreational fishing; estuarine habitats; numerous federally, state and locally protected marine and estuarine waters; watershed influences and impacts from eight million San Francisco Bay Area residents. Conservation Science helps solve specific management problems, enhance ecosystem protection efforts, and assist in the interpretation of the ecosystem for the general public.  In total, the sanctuary protects an area of 3,295 square miles off the northern and central California coast. Learn more about its unique geology, marine life, and history.


Point Reyes National Seashore contains approximately 80 miles of shoreline providing habitat for a plethora of marine and wildlife, and recreational access for hiking, tidepooling, picnics, and sightseeing. Beaches may be closed at various times of the year to better protect northern elephant seals and harbor seals during their pupping seasons, snowy plovers while they are nesting, or for visitor safety. Learn more about park beaches, conditions, access, beach fires permits, safety, pet rules and more.

Drakes Estero, located in the Phillip Burton Wilderness at Point Reyes National Seashore is home to the only west coast marine wilderness south of Alaska. It is one of the most protected estuaries in California, where fresh and salt water meet to create habitat for thousands of species of plants and animals. Made up of five branching bays, the 2500 acre complex includes 2300 acres of underwater wilderness—which is more than twice the size of Golden Gate Park in San Francisco. The wilderness area in the southern section of the park also includes a number of creeks, which filter out to the Pacific Ocean or congregate into one of three fresh water ponds, and a unique waterfall, which falls over the coastal bluffs right onto the beach. Learn about our work in protecting this unique resource.

Tomales Bay is a long narrow inlet of the Pacific Ocean approximately 15 miles long and averages nearly 1.0 miles wide, which effectively separates the Point Reyes Peninsula from the mainland of Marin County.  The bay forms the eastern boundary of Point Reyes National Seashore, and was formed along a submerged portion of the San Andreas Fault. It is an Ramsar site or international wetland of importance, designated by EAC in 2002

EAC Ocean & Watershed Partners


EAC Water Programs