Can turning off the main water damage your pipes?

Where the main valve is

FEMA says the main valve may be where the water pipe enters the house, and a second valve is often near the water meter (FEMA). Find yours before you need it. 404 Water Damage has a walkthrough: emergency water shut-off valves in Atlanta.

Old valves that won't turn

Valves that sit unused for years can stick. If the handle won't move with steady hand pressure, stop rather than reaching for a long wrench, and go to the valve near the meter instead. A plumber can replace a stuck main valve with a new one so it works the next time.

The water heater

If the water heater itself is the leak, A. O. Smith says to cut power and water first: switch off the heater's breaker for an electric unit, or turn the gas valve on the burner supply pipe perpendicular to the pipe for a gas unit. Then close the cold water valve on the pipe entering the top of the tank, or use the main if there isn't one (A. O. Smith). A. O. Smith adds: leave immediately and call the gas utility if you smell gas (A. O. Smith). See water heater leaking: what to do.

The valve at the meter in Atlanta

If the city has shut off service at the meter, don't turn it back on yourself. ATL311 says it is illegal for customers to restore their own service, and the meter may be plugged if they do (ATL311). For an emergency shut-off because of a burst pipe on private property, ATL311 says to contact a licensed plumber or call ATL311 at 404-546-0311 (ATL311).

Common questions

Should I drain the lines after shutting off the main?

Opening a faucet on the bottom floor lets water already in the pipes run out instead of leaking. Your plumber can tell you whether anything else is needed for the repair.

How do I know the main is fully closed?

Open a faucet. If water keeps flowing after the pressure drops, the valve may not be sealing. EPA WaterSense's meter check works too: with everything off, the meter shouldn't move (EPA WaterSense).