1908 Cistern Circles
The Verdict
"More than 170 brick and disc marked circles in San Francisco intersections mark buried emergency water cisterns, built between 1909 and 1913 after the 1906 fire. Each holds 75,000 to 200,000 gallons and the system is still maintained. The densest concentration is in the Mission, SoMa, and the Financial District."
What you need to know
What’s There
Brick or gold-painted circles, about three feet in diameter, mark the locations of underground emergency water cisterns at intersections across San Francisco. The city maintains around 170 to 177 of them, holding between 75,000 and 200,000 gallons each, for a combined capacity of over 11 million gallons.
The cisterns are part of the Auxiliary Water Supply System, built in response to the 1906 earthquake when broken water mains left firefighters with no way to stop the fires that destroyed much of the city. The system was built in the years after 1906, with construction ramping up from 1908 and the main expansion finishing in 1913, building on a smaller network of about 23 cisterns dating to the 1850s. The system is still maintained and operational. The San Francisco Fire Department tests and fills the cisterns regularly.
The circles are scattered across the city, with concentrations in older neighborhoods like the Mission, Hayes Valley, Nob Hill, and the Financial District. The gold-painted ones are the easiest to spot. Most are flush with the pavement at intersections and have a manhole at the center labeled CISTERN S.F.F.D.
Visiting
Hours: Always visible
Cost: Free
Best time to go: Anytime you’re walking the city. Rain makes the gold paint stand out more.
What to know: The highest concentration of cisterns is in neighborhoods that burned in 1906: the Mission, SoMa, and the Financial District. Look down at intersections for the brick or gold circles.
Getting There
Transit: Anywhere. They’re throughout the city.
Parking: N/A
Walking: Visible on any walk through central San Francisco neighborhoods.
