San Francisco, California Water Outage Today

San Francisco tap water system, by the numbers

Federal records name Sfpuc City Distribution Division as the public water system for San Francisco, with about 848,019 people on its mains. Customers know it as San Francisco Public Utilities Commission (SFPUC); the name on your bill is the one to call.

Source water and treatment in San Francisco

San Francisco does not collect its own raw water. Sfpuc City Distribution Division buys surface water from San Francisco Regional Water System and distributes it through its own mains.

What this means in an outage. Local crews can fix local mains, but not a failure at San Francisco Regional Water System. When that supplier cuts flow, San Francisco has only its tanks to fall back on, so check both its notices and those from San Francisco Public Utilities Commission (SFPUC).

Main breaks and shutoffs in San Francisco: the usual causes

These are the causes that match the record for San Francisco, listed roughly in order of how much they matter here.

• Long dry spells. The longest stretch without measurable rain since 2015 lasted 136 days, ending September 8, 2021. Dry soil shrinks and shifts around buried pipe, and breaks often cluster when the rain returns and the ground swells again.
• Older neighborhoods and pipe. 69.3% of occupied homes in San Francisco were built before 1970, against 35.5% nationally. Streets of that age tend to sit on cast iron and early steel mains that are near or past their design life, which is where most breaks start.
• Flooding and heavy rain. NOAA logged 83 flood, flash flood and heavy rain reports in San Francisco County from 2015 through 2026, and 4 days a year bring an inch of rain or more. High water can wash out the ground under buried pipe, flood pump stations and push treatment plants past their limits, which is why boil notices so often follow a flood.
• Digging and utility work. Street projects, fiber installation and excavation near buried pipe regularly cut mains in San Francisco with no warning, usually on a day with perfectly ordinary weather.
• Scheduled work, or a fault inside your own home. Utilities warn customers before a planned shutoff. If nothing was announced and the neighbors are fine, the cause is probably your shutoff valve, meter or pressure regulator.

San Francisco weather and water-main stress, 2015–2025

Weather stress on the water system in San Francisco is moderate: freezes and heat waves are limited, so breaks tend to follow age, ground movement and construction more than weather.

These counts come from a gridded reanalysis, which smooths out single-day extremes and can differ by a few degrees from an airport thermometer. Use them to compare seasons and years, not as official station records.

San Francisco boil water notices and EPA compliance record

EPA lists no health-based violations for Sfpuc City Distribution Division since 2015.

Boil water notices in San Francisco are precautions, not findings. When pressure drops, San Francisco Public Utilities Commission (SFPUC) tells affected customers to boil water until two rounds of lab tests are clean, a process that normally takes 24 to 48 hours after service is restored, under oversight from the State Water Resources Control Board, Division of Drinking Water.

Lead, older pipes and water quality in San Francisco

The most recent 90th-percentile lead result filed for Sfpuc City Distribution Division is 0 ppb (2024). The federal action level is 15 ppb, so that result is comfortably below it.

The age of the housing matters more than the utility's test average: 69.3% of occupied homes in San Francisco predate 1970 and 1986 was the year lead pipe and solder were banned. Flush the cold tap after an outage and ask San Francisco Public Utilities Commission (SFPUC) whether your service line is on its lead inventory.

Restoration times for water outages in San Francisco

Most repairs of an ordinary main break in San Francisco take half a day once the crew is on site. Bigger mains, deep bury and busy roads stretch that to a day or more. With 848,019 people on the system, a break on a main that feeds a whole district can leave thousands of homes dry at once, and crews may close valves several blocks away to isolate it.

San Francisco Public Utilities Commission (SFPUC) will post an estimated restoration time for a break that affects many customers; ask for the repair crew's estimate when you call.

How much water to keep on hand in San Francisco

With about 2.3 people in the typical San Francisco home, FEMA's one-gallon-per-person-per-day rule means 7 gallons covers three days and 32 gallons covers two weeks.

• 30.8% of homes are in buildings with 20 or more units. Upper floors lose pressure first, and rooftop tanks and booster pumps depend on building power.
• 61.8% of households rent. Tell your landlord or property manager about a leak or outage right away, since the shutoff valve may be theirs.
• Your water heater tank holds 30 to 50 gallons of clean water. Turn off the power or gas to it first, then drain from the valve at the bottom.
• Fill a tub or large containers early for toilets, cleaning and handwashing, and store drinking water separately in clean bottles.

San Francisco versus neighboring water utilities

Water outage pages for nearby cities

Oakland, CA · Fremont, CA · San Jose, CA · Stockton, CA