Utility shutoffs and safety

01 — The water shutoff

Turn the main valve clockwise until it stops. This prevents contaminated water from entering your home and clean water from draining out through broken pipes.

The main water shutoff valve controls all water flow into your home. In warmer climates, it is typically located outside near the water meter, often in a covered box at ground level near the street. In colder climates, it is usually inside, in the basement or utility room, near where the main water line enters the house.

Turning off the main water valve serves two purposes during a disaster. First, it prevents contaminated water from entering your home's plumbing if the municipal supply is compromised. Second, if a pipe inside your home has cracked or burst (common after earthquakes and freezing events), closing the valve stops the flow and prevents further flooding.

• Locate your main water shutoff valve now, before you need it. Walk to it, identify the handle type (gate valve with a round wheel or ball valve with a lever), and verify that it turns smoothly.
• If the valve is stiff, corroded, or difficult to close fully, FEMA recommends having it replaced before an emergency. A valve that will not close when you need it is worse than no valve at all.
• After shutting off the main valve, open faucets at the highest point in the house to relieve pressure and allow air into the lines. The remaining water in the pipes can be collected as an emergency drinking water source.
• Do not turn the water back on until you have confirmed that the municipal supply is safe and that your home's pipes are intact.

02 — The electrical main breaker

Switch individual breakers off first, then the main breaker. Turn off the electrical system when you smell gas, see structural damage, or anticipate flooding.

Your electrical breaker panel (also called the breaker box or load center) is usually located in the basement, utility room, or garage. It contains individual circuit breakers for each circuit in the house and a main breaker that controls power to the entire panel.

Situations that require turning off the main electrical breaker:

• You smell natural gas. Electrical sparks from switches, appliances, or even light switches can ignite leaking gas. Turn off the main breaker to eliminate ignition sources, then leave the house and call the gas company.
• Your home has sustained structural damage from an earthquake, tornado, or vehicle impact. Damaged wiring inside walls can arc and cause fires. Turning off power eliminates this risk while you assess the damage.
• Flooding is approaching or has entered the home. If you can safely reach the breaker panel before water reaches it, turn off all power. Water and electricity together cause electrocution.
• You see sparks, smell burning insulation, or observe scorched outlets or switches. These indicate an active electrical fault that could start a fire.

03 — Never touch the panel in standing water

If you cannot safely reach the breaker panel, do not try. Call your utility company and stay out of the water.

This is the scenario where pre-disaster preparation matters most. If a slow-moving storm or flood warning gives you advance notice, turn off the main breaker before the water arrives. In a flash flood or unexpected rapid water rise, evacuation takes priority over utility shutoff. Your life is worth more than preventing electrical damage.

04 — Locating your shutoffs before you need them

The best time to find your utility shutoffs is today. The worst time is during an emergency in the dark with water rising.

• Water: Find the main shutoff valve. Test that it turns. Know whether it is a gate valve (round wheel, multiple turns) or a ball valve (lever, quarter turn). Label it if it is not obvious.
• Gas: Find the gas meter and the shutoff valve on the supply pipe. The valve is typically on the pipe entering the meter from the ground. Turning it a quarter turn so the handle is perpendicular to the pipe closes the valve. Keep a non-sparking wrench (available at hardware stores for $10 to $15) attached to the meter with wire so it is always there when needed.
• Electrical: Find the breaker panel. Open the door and identify the main breaker. Know which individual breakers control which circuits (label them if they are not already labeled).
• Teach every adult in the household where each shutoff is and how to operate it. Post a simple diagram near each shutoff showing the OFF position. In an emergency, the person closest to the shutoff may not be the person who located it.

05 — The gas shutoff wrench

A non-sparking wrench kept at the gas meter ensures you can shut off gas quickly without creating a spark near a potential leak.

Most residential gas meters use a valve that requires a wrench to operate. The valve has a rectangular tang that must be turned a quarter turn so the tang is perpendicular to the pipe. A standard adjustable wrench works, but FEMA recommends a non-sparking wrench specifically because a standard steel wrench striking the steel valve can produce a spark, and a spark near a gas leak creates an ignition risk.

Non-sparking gas shutoff wrenches are available at hardware stores for $10 to $15. Many are designed with a fitted slot that matches the valve tang, making the operation faster and easier in the dark or under stress. Secure the wrench to the gas meter or to the pipe near the meter with a piece of wire, so it is always in the same place and immediately accessible.