How to Shut Off Your Home's Water in an Emergency

A burst pipe, a failed washing machine hose, or a running toilet that will not stop - any of these can send water pouring into your home fast. Knowing exactly how to shut off the water before it becomes a disaster is one of the most useful things a homeowner can learn. It takes five minutes to learn and could save thousands of dollars in water damage.

Find Your Main Shutoff Before You Need It

The single most important preparation you can do is locate your main water shutoff valve before an emergency happens. When water is spraying from a pipe, you do not want to be searching for it.

In most California homes, the main shutoff is in one of these locations:

• Near the street, in a concrete box: Most properties have a water meter box embedded in the ground near the curb or sidewalk. Inside, there is usually a shutoff that controls water to the whole property. Turning this one off requires a special key (a water meter key, sometimes called a meter box wrench), which costs around $10 to $20 at hardware stores. This is the utility's shutoff.

• At the meter inside or near the foundation: Many homes have a second shutoff on the house side of the meter, often near where the main line enters the foundation. This is your shutoff as a homeowner and does not require a special key.

• In a utility closet, garage, or basement: In older homes and in many homes with slab foundations, the main shutoff may be on an interior wall, typically where the water line first enters the livable space.

Walk through your home now, identify where your shutoff is, and make sure it is accessible. Valves that have not been turned in years may be stiff - test it now so you know it works.

How to Shut Off the Main Water

Once you find it:

Gate valve (round wheel-style): Turn it clockwise ("righty-tighty") until it stops. Do not force it if it is stiff - gate valves can break if overtightened when old.

Ball valve (lever-style): Rotate the lever 90 degrees so it is perpendicular to the pipe. This type shuts off more quickly and is more reliable.

After shutting off the main, open a faucet on a lower floor to release pressure remaining in the lines. This is especially useful when you need to work on pipes.

Individual Fixture Shutoffs

For smaller emergencies that involve just one fixture, you do not need to shut off the whole house. Most fixtures have their own local shutoffs:

Toilet: There is almost always a small oval or football-shaped valve on the wall or floor behind the toilet. Turn it clockwise.

Sink: Look under the sink cabinet. There are usually two valves (hot and cold) on the supply lines running up from the floor or wall. Turn them clockwise.

Washing machine: Most have hot and cold shutoff valves on the wall behind the machine. If hoses are connected to a recessed box in the wall, the valves are inside that box.

Water heater: There is a cold water shutoff on the incoming supply line at the top of the unit.

Knowing these locations means a leaking toilet or under-sink supply line does not have to take out the whole house's water while you wait for a plumber.

What to Do in an Active Emergency

If water is already flowing from a broken pipe or failed appliance:

1. Shut off the nearest local valve first - this stops the immediate flow.
2. If you cannot find or reach a local valve, go straight to the main shutoff.
3. Turn off the power in any room where water is getting near outlets or panels - water and electricity are a serious hazard.
4. Call a plumber - active pipe leaks typically require professional repair.
5. Start removing standing water as quickly as you can to reduce secondary damage. Towels, a wet/dry vac, or a mop all work.

After Shutoff: What Comes Next

With the water off, the immediate emergency is contained. Do not restore water until the source of the problem is identified and repaired. Turning water back on before fixing a break will just restart the flow.

Document the damage with photos before cleaning up - your homeowner's insurance may cover water damage depending on the cause, and photos support a claim.

Practice Run: Do This Today

If you have never tested your main shutoff, now is a good time. Turn it off, open a faucet to confirm no water flows, then turn it back on. Check that the valve seats properly and water restores fully. If the valve is old, stiff, or corroded, having it replaced by a plumber is a reasonable precaution.

Bottom Line

Sources and editorial notes

Prices and permit requirements vary by location, property, equipment, and scope. Treat price ranges as planning estimates and confirm current requirements with the relevant authority and contractor.

• California Contractors State License Board - when a contractor license is required
• US Department of Energy - Energy Saver
• US Consumer Product Safety Commission - home safety

Related guides

• What to Do When a Pipe Bursts
• Water Heater Leaking from the Bottom: Shutoff and Damage-Control Guide
• Outlet Sparking: What to Turn Off and When to Leave the House

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