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The San Francisco Bay-Delta Estuary is the largest estuary system on the west coasts of both North and South America, encompassing 1,600 square miles, ranging from the salty waters of San Francisco Bay to the brackish waters of the Sacramento-San Joaquin Delta. The Estuary's vast upstream watershed drains more than forty-percent of California's land-mass, including the freshwater streams of the Sierra Nevada and Coast Ranges.

The San Francisco Bay covers 400 square miles with an average depth of fourteen feet with depths of 360 feet at the Golden Gate. Even though the Bay has shrunk by a third in the last 150 years, and only about twenty-five percent of its original wetland, riparian, and tidal mudflat habitat remain, the Bay still supports the only urban commercial fisheries in the nation. The Bay is also the largest harbor on the U.S. Pacific Coast, with more than 67,000,000 tons of cargo passing annually through the Golden Gate.

More than one million shorebirds and waterfowl make their home on bay marshes while millions of others use it as a migratory destination or a rest and reenergizing food stop. The Delta is a major nursery for fish and invertebrates as well as a highway for migrating salmon and steelhead. The ecosystem supports some 750 species of fish, animals, and birds, many of which are endangered. In addition, hundreds of non-native invasive species, including algae, marsh plants, invertebrates, and dozens of fish species, negatively impact an already damaged eco-system.

Thanks to The Bay Institute for the above information:

Save The Bay Presents "The Bay Classroom"

To learn more our San Francisco Bay go to The Bay Classroom

Tips for Saving Water at Home

Click here for tips to keep the water flowing!


United States Geological Survey (USGS) website on the Bay, the estuary and watershed

San Francisco Bay Model provides scientists, educators and citizens interested in the Bay and Delta unique opportunity to view the complete system at a glance