About the Bay

The San Francisco Bay-Delta Estuary is the largest estuarine system on the west coasts of both North and South America.  A rich national treasure, it ranges from the salty waters of San Francisco Bay to the brackish waters of the Sacramento-San Joaquin Delta, and contains over 90 percent of the state’s remaining coastal wetlands. The Estuary’s vast upstream watershed drains more than 40 percent of California’s land mass, including the freshwater streams of the Sierra Nevada and Coast Ranges.

At a Glance

The estuarine system ranges from the salty waters of San Francisco Bay to the brackish waters of the Sacramento-San Joaquin Delta,

Century of Destruction

By the late 20th century, only seven percent of the original, historic tidal wetlands remained.

Fish & Wildlife

The watershed supports some 750 species of fish, animals and birds, including 18 that are listed as threatened or endangered.

The Shrinking Bay

Nearly 40% of the historical Bay's aquatic ecosystem has been lost, including tidal wetlands, tidal mudflats and open water area.

Historic Marshlands

Partially aquatic, partially terrestial, the San Francisco Bay-Delta Estuary marshlands once covered 542,000 acres.

Glossary

From AF (acre foot of water) to zoning, the glossary demystifies the terminology that is used to explain the West Coast's largest watershed.