Historically, San Francisco Bay was a thriving estuary supporting thousands of plant and animal species, and sustaining a wide diversity of native cultures.

Early accounts tell of a place where the sky darkened by the flights of ducks and geese, salmon runs coming up the Delta so thick that you had the impression you could walk across their backs all the way to the other shore, dense oak forests, and grasses that stayed green long after the winter rain season and grew higher than a man on a horseback.  

This was a place surrounded by wildlife that we no longer see today – Tule Elk, antelopes and Grizzly bears, and thousands and thousands of migratory shorebirds – so many that duck hunters, up until the 1850’s describe being able to kill twelve birds with one shot.

This was a Bay that would double in size in the span of six hours as the tide came in over the hundreds of thousands of acres of wetlands that ringed its shores.   

The Era of Bay Fill (Gold Rush to 1960)

Starting with the Gold Rush, these wetlands, such a prominent feature of the Bay for so many years, began to disappear, marking the beginning of more than a century of Bay fill.

As speculators from around the world rushed in, the remote, sleepy town of Yerba Buena grew from no more than 800 people in 1847 to an overflowing, ever-expanding San Francisco of 50,000 residents by 1855.

With nearby land scarce, Yerba Buena cove became one of the first parts of the Bay to be filled, followed by Mission Bay, and within a short number of years, virtually all San Francisco’s tidal lands.  Much of the Bay’s marshes were sold off by the State of California for $1 an acre.

Decades later, Moffett Air Field was established in South Bay marshes in 1932, followed shortly after by the creation of Treasure Island, the Alameda Naval Air Station, Mills Field (later SFO) in San Francisco, and the San Pablo Bay fill project of Hamilton Army Air Field.

By 1950, 137,000 acres of baylands had been cut off from the Bay, and by 1961, 90% of the Bay’s wetlands were gone – and every city had plans to fill in their portion of the Bay,

During these years, all sorts of ideas for filling the Bay were proposed. New cities, a nuclear power plant on the Bay’s edge in San Mateo County, miles of new freeways, and even the virtual eradication of the Bay as an estuary. The later being the plan of a theatrical producer, John Reber, who proposed to turn the bay into a complex of shipping facilities, air bases, transportation networks, and two massive dams.

While Reber’s plan never broke ground, many others did and by 1961, the Bay was a third smaller than it was a little more than a century before.

Foster City, initiated in 1959, was perhaps the biggest development to go through – using 14 million cubic yards of fill to turn Leslie Salt’s former Bay marshlands into a new suburban town of 30,000 people.

Saving the Bay (1960s to present)

That same year saw the publishing of a map by the Army Corps of Engineers, later released by the Oakland Tribune, estimating that if current development rates continued, by 2020 the Bay would be nothing but a mere shipping canal.

This prompted the founding of Save the Bay in Berkeley by Catherine Kerr, Sylvia McLaughlin, and Ester Gulick in 1961.  After seeing so many years of their beloved bay being abused, they organized an unprecedented campaign to save it. Within two years, the group had stopped the Sante Fe Railroad Company from filling in 2,000 acres of the Berkeley shoreline, doubling the size of the city. Within four years, their movement had so successfully mobilized the public and pressured State legislators with endless phone calls, letters, and visits from chartered buses, that in 1965 the McAteer-Petris Act was signed into law, creating the Bay Conservation and Development Commission (BCDC), the world’s first coastal protection agency.

A few bay-fill developments snuck through immediately before the effective date of the McAteer-Petris Act (including Redwood Shores and the massive Bay Farm Island project in Alameda), and the creation of BCDC itself has not stopped all attempts to fill in the Bay. Involvement of the public has continued to play a key role in preserving and restoring what’s left.  

In 1968, a development group lead by David Rockefeller proposed to create a “new Manhattan” by filling in 27 miles of the San Mateo County shoreline using fill from a leveled San Bruno Mountain. Save The Bay worked for a decade to kill the audacious plan.

In the 1980s, Mobil Oil proposed to build thousands of houses on Bair Island directly south of Redwood Shores on the Peninsula. The Redwood City Council approved the project, but in 1982 voters led by Ralph Nobles and the Friends of Redwood City narrowly overturned the approval through a local referendum. Mobil Oil later sold the 3,000 acre property, and it was acquired in 1997 by the Peninsula Open Space Trust for $15 million. Bair Island is currently undergoing restoration back to its native marshland.

The 1980’s also saw the “Egret Bay” proposal to turn a former North Bay marsh into 4,500 homes clustered around lagoons. After a series of lawsuits, the 1,500 acre site was sold to the federal government in 1989 for $6.5 million. It’s now thriving habitat once again.

In 1998, the San Francisco International Airport launched a $75 million public relations campaign to significantly expand the airport by filling in the Bay. After a multi-year fight led by Save The Bay, the SF Board of Supervisors halted the plan and banned future SFO bay fill attempts.

Today, historic restoration efforts continue, as does our decades-long fight against inappropriate bayfront development. Scientists estimate that 100,000 acres of marshland are needed for a healthy Bay. Well on our way, Cargill’s 1,436 acres of salt ponds in Redwood City, already approved for inclusion in the Don Edwards National Wildlife Refuge and surrounded by other wetlands under restoration, is one of our best opportunities to help meet this goal and make the San Francisco Bay thrive again.

In the early 1970s, the San Francisco Chronicle editorialized, “It should not be necessary to warn legislators representing this region that people in the Bay Area will be unforgiving to those who fail in their responsibility to save the Bay from unwise exploitation, disfigurement and diminishment.”

Unfortunately, four decades later, it is still necessary to save the Bay – and to be unforgiving to those who aim to destroy it.

For more information on the history of the San Francisco Bay and efforts to save it, see KQED’s Emmy-Award-winning documentary Saving the Bay, or Save the Bay’s list of achievements from the past 50 years.