How to Shut Off Your Water in a Plumbing Emergency

The main shutoff controls all water entering the house. In cold climates, it is typically inside the structure where the water main enters — basement, utility room, or crawl space near the front foundation wall. In warm climates and slab-on-grade homes, it may be outside near the meter, in the garage, or under the kitchen sink. Gate valves (round wheel handle) require multiple clockwise turns to close. Ball valves (lever handle) close with a quarter-turn perpendicular to the pipe. Test yours once a year — a main shutoff that hasn't moved in decades may be seized when you most need it.

Toilets: the oval chrome valve on the wall behind the toilet. Turn clockwise. Sinks: hot and cold supply valves under the cabinet, behind the supply lines. Washing machine: inline valves on the hot and cold hoses at the wall connection. Water heater: the cold-side supply valve on the top of the unit. Refrigerator ice maker: typically a small saddle valve on the cold water line under the sink or behind the unit. Knowing each of these lets you stop water at one fixture without shutting off the whole house.

If the main inside shutoff fails or is inaccessible, every home has a second shutoff at the water meter near the street. This is inside a covered underground box — typically a round or rectangular lid flush with the ground near the curb or property line. Closing the meter shutoff requires a water meter key (a T-shaped tool available at hardware stores for under $10). Keep one accessible. This is the last resort before calling the utility company.

After shutting off the main: (1) Open the lowest faucet in the house to drain pressure from the supply lines. (2) Document the damage with photos for insurance purposes. (3) Turn off the water heater (gas: turn to PILOT; electric: turn off the breaker) — heating an empty tank damages the heating element. (4) Call a licensed plumber. Turning the water back on before the damaged section is repaired causes immediate re-flooding.

The correct time to learn your shutoff locations is now — not during an emergency at 2 AM with water flowing into your kitchen. Walk through your home and locate: the main shutoff, the toilet shutoffs in each bathroom, the sink shutoffs under each sink, and the water heater shutoff. Confirm each valve turns. Consider attaching a label to the main shutoff valve so any household member or house-sitter can find it instantly.