The middle of a burst pipe is the worst possible time to learn where your shut-off valve is. Water is moving fast, you're not thinking clearly, and every minute of searching is more water in the house.

Ten minutes today prevents that entirely. Here's what to find and how to test it.

The three shut-offs worth knowing

1. Fixture shut-offs

Small valves directly under sinks and behind toilets, controlling that fixture only. If the problem is a single leaking faucet or a running toilet, this is all you need — the rest of the house keeps working.

Look under each sink. You'll usually find two, hot and cold. Behind a toilet, one on the supply line near the floor.

2. The main house shut-off

This stops water to the entire house and is the one that matters in a real emergency. In Daly City homes it's most often found in the garage, in a utility closet near the water heater, or on an exterior wall where the supply enters.

It will be either a gate valve — a round wheel you turn clockwise, several full rotations — or a ball valve, a lever you turn a quarter turn until it sits across the pipe.

3. The street-side meter valve

In a box at the property line, usually under a metal or concrete lid near the sidewalk. This is the backup if your main house valve fails, which older gate valves sometimes do.

It often needs a meter key to operate. They're inexpensive, and keeping one where you'd actually find it in a hurry is worth the small cost.

Test them now, not later

This is the part people skip, and it's the part that matters. A valve that hasn't been operated in fifteen years may well be seized — meaning you have a shut-off that doesn't shut off, and you'll discover that at the worst moment.

Go and turn each one fully closed, then fully open. Note whether it moves freely and whether water actually stops. If a valve is stiff, drips at the stem when operated, or won't fully close, it needs replacing while that's a scheduled job rather than an emergency.

Do this now

  • Locate all three shut-off types and note where they are
  • Operate each one fully closed and fully open
  • Confirm water actually stops at the fixture
  • Buy a meter key and keep it somewhere findable
  • Show everyone in the household where the main valve is

Avoid

  • Forcing a seized valve with excessive leverage
  • Assuming a valve works because it looks fine
  • Leaving the meter key in a drawer nobody knows about
  • Testing for the first time during an actual leak
  • Ignoring a valve that drips when operated

Take a photo of your main shut-off, including enough of the surroundings to find it, and save it somewhere everyone in the house can reach. In an emergency, a house-sitter or family member who has never looked for it can act immediately.

What to do when a pipe bursts

A burst pipe is an emergency — our line is answered 24 hours.

  • Shut off the main. The whole-house valve, not the fixture valve. Do this first, before investigating anything.
  • Cut power to affected areas if water is anywhere near outlets, panels, or appliances — at the breaker, and only if you can reach it safely and dry.
  • Open the lowest taps in the house. This drains the remaining pressurized water downward and away from the break.
  • If it's a water heater, shut its gas supply or breaker as well as the water.
  • Then call. With the water off, the emergency is contained and you can talk through it properly.

A note on older Daly City homes

Gate valves — the round-wheel type — were standard in the mid-century tracts and are the type most likely to have seized or to fail when finally operated. If your main shut-off is a gate valve that's never been touched, replacing it with a quarter-turn ball valve is a small job that removes a real risk.

It's the kind of thing worth doing on a Tuesday, rather than discovering on a Sunday night.