How to Shut Off the Water to a Burst Pipe

Water is coming through a ceiling or running across a basement floor and every second counts. The instinct is to mop or catch it, but nothing helps until the pressure is off the line. The main shutoff is the whole job, and the time to learn where it is and whether it turns is before an emergency, not while standing in an inch of water.

Cut power to any circuit near the water

Before wading into standing water, go to the breaker panel and switch off the circuits serving that area, or the main breaker if that is faster. Water reaching outlets, a furnace, or a power strip is a shock hazard. If the panel itself sits in the wet area, stay out and call the utility and the fire department.

Find the main shutoff

Look where the supply line enters the house: a basement or crawlspace wall on the street side, near the water meter, or in a utility closet or garage in houses on a slab. In some homes the only valve is the curb stop, a covered box near the street or sidewalk that needs a long curb key to operate.

Close the valve all the way

A gate valve has a round wheel handle and turns clockwise, several full rotations, until it stops. A ball valve has a lever and takes a quarter turn, closed when the handle sits crosswise to the pipe. Do not force a seized gate valve past resistance, because old stems snap and then nothing closes.

Drain the remaining water

With the main closed, open the lowest faucets in the house, a basement laundry tub or a first-floor tub, and then faucets on upper floors. That empties the standing water still in the pipes and drops the pressure feeding the break.

Shut down the water heater

An electric water heater must be switched off at its breaker, because the elements will burn out within minutes if they run dry. On a gas heater, turn the control dial to Pilot or Vacation. Leave it off until the system is repaired and refilled.

Call a licensed plumber

Once the water is off, the repair itself is a plumber's job, and the insurer will want the loss reported promptly. Photograph the damage before removing anything.

If the shutoff will not close or there is not one inside. A curb stop, a valve that spins without stopping the flow, and any shutoff in an unoccupied property are a call to the water utility, which has an emergency line and the tool to close the street valve.

Before the next freeze. Tag the main shutoff, confirm it turns twice a year, and make sure everyone in the house knows where it is.