Find your main water shutoff valve
If water is coming in right now, go straight to the valve: it's usually where the water line enters the house, often on the wall facing the street, in the garage, or in the basement. Turn a round handle clockwise until it stops, or turn a lever so it sits across the pipe. If nothing's leaking yet, take ten minutes today to find it. Tie a tag on it once you've found it. In a real leak, nobody wants to be hunting for it with a flashlight. Finding it is the first job on the new homeowner checklist.
Why it's worth ten minutes now
Most people look for the for the first time while water is spreading across the floor. Finding it now, and making sure it actually turns, means that if a pipe ever lets go, you already know where to go and what to do.
What usually sends people looking for it
Most often in winter, in unheated spots like garages, crawl spaces and outside walls.
The flexible hoses feeding sinks, toilets and washing machines can split without warning.
An old tank can split and dump a lot of water fast.
A slow drip at a joint can suddenly get much worse.
| Valve type | How to turn it off |
|---|---|
| Round wheel handle (gate valve) | Turn clockwise until it stops. It may take several turns. |
| Straight lever handle (ball valve) | Turn a quarter turn so the lever sits across the pipe. |
| No handle, square nut (city side, at the meter) | Needs a meter key. A quarter turn closes it. Some water utilities ask you to call them instead of turning it yourself. |
| Stuck and won't turn | Don't force it with a wrench. Use the city shutoff and call a plumber. |
Find it and test it
- Start where the water comes inIn warm climates the valve is often outside, on the wall facing the street, near a hose spigot. In colder areas, look in the basement or crawl space on the street side, in the garage near the water heater, or in a utility closet.
- Follow the pipeLook for the biggest water pipe, usually 3/4 or 1 inch copper or plastic, coming up out of the floor or ground. The valve is on that pipe, before it splits off to the rest of the house.
- Try it, gentlyTurn it off, then open a faucet to make sure the water stops. Turn it back on slowly. An old gate valve that hasn't moved in years can be stiff. Firm hand pressure is fine, but don't put a wrench on it and force it.
- Label itHang a tag on it that says MAIN WATER SHUTOFF, and show everyone in the house where it is, including anyone who house-sits.
- Know your backupIf the house valve ever fails, the city's shutoff is in the meter box, usually near the curb. It takes a meter key, which costs about $15 at a hardware store and is worth keeping in the garage.
Watch it done
- You can point to the valve on the main pipe, before it branches off
- A faucet stops running when the valve is turned off
- Water comes back normally after you turn it on slowly
- The valve is tagged MAIN WATER SHUTOFF and everyone at home knows where it is
Valve won't budge or close? Don't force it. Use the city shutoff at the curb with a meter key.
If the main valve won't close
If the main valve won't budge or won't close all the way, use the city shutoff in the meter box near the curb. You'll usually need a meter key.
Once the water is off, open the lowest faucet in the house to drain the pipes and take pressure off the leak. Turn off the water heater too, so it isn't heating an empty tank.
What a pro typically charges (a rough estimate; prices vary by area): Emergency plumber visits often cost $200–$500 or more after hours. Replacing a main shutoff valve usually runs $300–$700.
Find a plumber near you