Historic Landmarks of San Francisco

Treasure Island (T.I.) ceased being a Naval base in 1997, seven years after the state plaque was dedicated. T.I. is now considered to be a neighborhood of the City and County of San Francisco, with about 3,000 (as of 2022) permanent residents. The island boasts a couple of restaurants, a supermarket with deli, a winery, and a brewery. There is now a ferry running daily between the San Francisco Ferry Building and the Treasure Island Ferry Terminal.

Further development on T.I. must wait until certain problems are resolved:

• Seismic issues: filled land is subject to liquefaction during severe earthquakes, as happened in San Francisco’s Marina District during the 1989 Loma Prieta temblor. In that neighborhood alone four people died and millions of dollars of damage resulted. Ironically, both the Marina District and T.I. were formed from filled land in order to provide a site for a World’s Fair.
• Traffic Congestion: more people mean more cars, thus adding vehicles to the already overcrowded Bay Bridge, especially during commute hours. The new ferry will no doubt help, but some people will still need or prefer to use their own wheels.
• Toxic Waste: In the 56 years (1941-1997) it controlled T.I., the Navy managed to contaminate the island with a veritable laundry list of toxic materials, including (but not limited to) PCB’s, dioxins, lead, arsenic, and PAH’s. There are even remnants of the radioactive isotopes radium-226 and cesium-137. Clearly this problem must be dealt with before further development is allowed.
• Rising Sea Level: Unlike neighboring Yerba Buena Island, which rises to a height of over 300 feet, the average elevation of T.I. is only about ten feet, making it vulnerable to future changes in sea level.

If these problems can be solved we can expect the population of T.I. (and Yerba Buena Island) to increase over the coming years.

Due to construction (2022), the plaque has been moved from its original site (the grassy median of Treasure Island Road, just south of its intersection with Clipper Cove Road) to a new site (Avenue A just south of its intersection with 9th Street). Whether or not this location is permanent is unclear.