The Evolving Story
What Are We Building On?
An Old Foundation for the New Exploratorium
Winter 2011/2012
Our new waterfront site is steeped in rich San Francisco history.
Image of young museum visitor playing with an exhibit

Imagine you're standing where the new Exploratorium is now taking shape, at the foot of Green Street in San Francisco, between the Ferry Building and Fisherman's Wharf. But instead of being in the present-day city, you're back in Gold Rush times, when gamblers and sailors and fortune-seekers roamed the red-light waterfront district. What would you see?

OK, so it's a trick question.

If your 1840s doppelganger got to where the present-day Embarcadero meets Piers 15/17, he or she would be hard-pressed to find a place to stand. Your time-traveling twin would be swimming, in very deep, very cold water.

A forest of ships' masts would separate the swimmer from the shoreline, which would be much farther inland than the present one. In fact, the present-day Transamerica Pyramid at Washington and Montgomery Streets, six blocks inland from the current waterfront, would have been beachfront property in 1847.

"Many San Franciscans, perhaps, and I'm sure many visitors, don't realize that the waterfront of San Francisco is not its original waterfront, " says Jim Delgado, Director of Maritime Heritage for the National Oceanic & Atmospheric Administration (NOAA). "In fact, it's a huge curving seawall that was built in the twentieth century to help enclose all of San Francisco's downtown, and all the fill that had been dumped in."

Layers of Time—and Trash
Standing on the Embarcadero today, you're like the figurine on top of a "layer cake of time and human history," says Delgado. Thirty or so feet down is the original bay bottom. Hundreds more feet of mud and you come to a bedrock of serpentine, laid down in the Cretaceous period.

Coming back up to more modern layers, you've got Gold Rush–era debris from ships, such as rotted wood planks, broken bottles, and the odd anchor. In some spots you have the ships themselves, used first as warehouses, then burned, or simply sunk to serve as landfill that extended the city ever further into the bay. There are also tons of sand, hauled down from the hills, rubble from the earthquakes of 1868 and 1906, and more modern fill of asphalt and concrete.

Saved by the Seawall
With all the rubble and sand, what keeps that part of the city from shifting under our feet even more than it already does? Thanks go to the seawall. Built in stages from 1878 to 1915, it holds the city in like a Victorian corset. The massive rock and concrete wall is anchored in place. "It goes deep down," says Delgado. "And it's capped, and that cap is of course today what the streets now run over."

Those streets along the waterfront began as major arteries for trade, routes along which covered wagons and then trains and trucks transported goods from ships to the marketplace. When the bulk of Bay Area shipping moved across the bay to Oakland, the city began to turn its back on its own ailing piers. A raised freeway erected in 1964 served as the physical divider between a thriving downtown and a dilapidated waterfront.

The most recent transformation began in the wake of the 1989 Loma Prieta earthquake, which severely damaged the Embarcadero Freeway. With the freeway gone, the city began to turn once again towards the bay. Anchored by the new AT&T Ballpark and the transformation of the landmark Ferry Building, the current rediscovery and reinvention of the Embarcadero reminds us that our history is of a city grown to serve a port rather than the other way around.

The Exploratorium's new campus at Piers 15/17 heralds the next phase of this transformation. The museum is doing its part to reintroduce San Francisco to its glorious and historic waterfront—all from a site that a century and a half ago was in the realm of the fishes.

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