Closing the main in four steps
Find the valve
It is usually where the water line enters the house, often in a basement, utility room or crawl space, or near the water heater.
Turn it clockwise
A round wheel valve turns clockwise to close. A lever valve closes when the handle is perpendicular to the pipe.
Open a low tap
Open a faucet at the lowest level to drain the pipes.
Check that the flow stopped
Faucets should run down to a trickle and stop. Then call a plumber.
If the valve does not turn or leaks around the stem, do not force it. Call a plumber and us, and shut the supply at the street if you have the key and know where it is.
Where main shutoffs tend to be
| Home type | Common location | Tip |
|---|---|---|
| Basement home | Near the front wall where the line enters | Look near the meter and water heater |
| Crawl space home | Inside the access hatch or a utility closet | Check the closet by the water heater |
| Slab home | Utility room, garage or an exterior box | Look near the water heater and hose bibs |
| Home on a private well | At the well pressure tank | Turn off the pump power too |
| Older home | Wherever the plumber put it | Walk the perimeter and check the meter |
Municipal water, districts and wells around Mahopac
Parts of the Town of Carmel are served by town water districts, and the county hazard plan refers to them. Other homes use private wells. If you are on a district, the valve at the street, called a curb stop, usually belongs to the utility, and tampering with it can be prohibited. Ask your water provider before using it.
If you are on a well, shutting off the pump and the main closes the house system. Our pages for Mahopac Falls and Baldwin Place describe which town covers each address, since they differ across the county line.
Fixture shutoffs that stop smaller leaks
| Fixture | Where the shutoff is | Direction to close |
|---|---|---|
| Toilet | Small valve on the wall or floor behind the bowl | Clockwise |
| Sink | Two valves under the cabinet | Clockwise |
| Washing machine | Two valves on the wall behind it | Clockwise or quarter turn |
| Dishwasher | Valve under the sink or in the cabinet | Clockwise |
| Water heater | Cold supply valve above the tank | Clockwise |
Vacations, smart shutoffs and leak sensors
Closing the main before a trip is a cheap precaution. If you travel often, a smart shutoff valve can close the main when a leak sensor detects water, and it can alert your phone. Leak sensors on the floor near the water heater, washer and sump pit give an early warning at very low cost.
A plumber can install a valve and tell you whether a pressure reducer would also help reduce stress on your pipes.
When the main is stuck or leaking
Older gate valves can seize or leak at the stem. If the valve will not turn without force, stop. Forcing it can snap the stem and make the problem worse. Call a plumber and ask about replacing it with a ball valve, which turns a quarter turn and is less likely to seize.
If you cannot reach the main at all, a plumber or the water provider can shut off the supply outside the house. This is another reason to know ahead of time who to call.
Mistakes people make when water is running
- Searching for the main in the dark with no flashlight.
- Turning the valve the wrong way and opening it further.
- Shutting off the water but leaving the water heater on, which can damage the tank if it runs dry.
- Walking through wet rooms to reach the panel or the valve.
- Waiting to call for help until the water has already spread to other rooms.
Cannot stop the water
Call the 24/7 line and we will talk you through it.
Make the shutoff easy before you need it
- Find the main and every fixture shutoff in the house and put a tag on each.
- Test the main once a year so it does not seize.
- Ask a plumber to replace a stuck gate valve with a quarter-turn ball valve.
- Show everyone in the household where the main is.
- Keep a flashlight and a wrench near the valve if it needs a tool.
What to do after the water is off
Turn off breakers to wet areas only if the panel is dry. Photograph the leak and the water before cleaning, and call your insurer. Move belongings to a dry place and keep people out of rooms where water reaches outlets.
Then call for extraction and drying. See water extraction and water heater leak cleanup for what happens next. If a washer or dishwasher caused the leak, appliance leak water damage explains cleanup.
Main shutoff questions
Clockwise to close for a wheel valve. A lever valve is closed when the handle is across the pipe.
Do not force it. Call a plumber and us, and ask your water provider about shutting off at the street.
Many people do, especially in winter. A plumber can also install a smart shutoff.
It usually belongs to the utility, so ask the water provider first.
The main after the pressure tank and the power to the pump, so the pump does not run dry.