15 Neighborhoods
San Francisco’s Marina District, October 1989. A vehicle crushed under the third story of an apartment building that collapsed during the Loma Prieta earthquake.
Photo: Agence France-Presse/Adam Teitelbaum
When Only Seawater Will Work
AWSS Map
Map key
Red: Not covered by San Francisco’s AWSS (Auxiliary Water Supply System) firefighting seawater system.
Black: AWSS high-pressure water pipe.
Blue: San Francisco Supervisor district:
1 Richmond District
2 Marina District
3 North Beach
4 Sunset District
5 Haight-Ashbury
6 South Beach
7 Forest Hill, St. Francis Wood, Inner Sunset
8 Noe Valley
9 Mission District, Bernal Heights, Silver Terrace
10 Potrero Hill, Silver Terrace, Hunters Point
11 Ingleside, Crocker-Amazon
Pump Station: A building with machines that can pull seawater from the Pacific Ocean.
**Note: During a fire disaster, locations that are farther away from an AWSS pump station will have little or no access to firefighting seawater.
Today, only the east side of San Francisco is covered by the AWSS (Auxiliary Water Supply System) firefighting water system.
AWSS is a seismically safe water network that uses high-pressure fire hydrants and pump stations to draw an unlimited supply of seawater from the Pacific Ocean.
The system was built specifically for the City in 1913, after San Francisco’s drinking-water system failed during the 1906 earthquake.
AWSS is separate and distinct from San Francisco’s drinking-water system, which Mayor Daniel Lurie and City agencies alternately refer to as:
Emergency Firefighting Water System.
Potable Emergency Firefighting Water System (Potable means “safe to drink”).
Why Santa Rosa, Lahaina, and Los Angeles burned
A drinking-water system is a fragile, low-pressure system that is not made to handle the volumes of water needed to fight a massive, out-of-control firestorm.
To extinguish a firestorm, the combustion source needs to be covered with enough high-pressure water to remove the heat.
For coastal cities such as San Francisco, Lahaina, and Los Angeles, the Pacific Ocean is the only reliable source of unlimited, high-pressure water.
No AWSS coverage
Bayview Heights
Crocker-Amazon
Excelsior
Ingleside
Little Hollywood
Merced Manor
Mission Terrace
Oceanview
Parkside
Portola
Richmond District, west of 12th Avenue
Sea Cliff
Stonestown
Sunnyside
Sunset District, west of 19th Avenue
The 2026 Plan: 1 Drinking-Water System, 3 Earthquake Fault Lines
The San Francisco Bay Area’s water resources and the San Andreas, Hayward, and Calaveras earthquake fault lines.
Image: San Francisco Public Utilities Commission
Understanding the PUC’s plan
Overview
The San Francisco Public Utilities Commission (PUC) manages two water systems: San Francisco’s drinking-water system and the AWSS firefighting water system.
As of May 2026, Mayor Daniel Lurie and the City of San Francisco are actively promoting and planning to use San Francisco’s drinking-water system for emergency firefighting water. Since 2010, the PUC has done nothing to expand the AWSS system across San Francisco, and has no plans to do so.
Hetch Hetchy Water System
The Hetch Hetchy Water System provides drinking water for the San Francisco Bay Area. Its water pipes (transmission mains):
Bring San Francisco’s drinking water 167 miles from the Sierra Nevada mountains;
Cross two major earthquake faults: the Calaveras Fault and the Hayward Fault;
Cross the San Francisco Bay;
Run along the San Andreas Fault before reaching three terminal reservoirs—Sunset, Merced Manor, and University Mound—in the southern areas of the City.
From a retired San Francisco fire official
The PUC’s plan states that Sunset Reservoir can be refilled within 24 hours after a major earthquake. However, based on public testimony from over 60 active and retired San Francisco fire officials, the PUC’s statement is only speculation.
Does it make sense to bet the lives of entire neighborhoods on an old, fragile drinking-water system that will immediately break during a 7.9M earthquake?
Why, after 16 years, are the City of San Francisco and the Public Utilities Commission still refusing to: 1) Expand the AWSS system to all of San Francisco, and 2) Use the Pacific Ocean, which is available to three sides of the city?