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Advanced Plumbing and Rooter Service

231 Market Place, Suite 540
San Ramon, CA 94583

Phone: 925-383-6100

C-36 License #782789

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How To Shut Off Main Water Line

Any experienced plumber can tell you that there comes a time in every household where the main water supply needs to be shut off. Knowing how to shut off your main water line is one simple piece of information that can save you volumes in effort, time, and cost should a plumbing emergency arise. While you are waiting for your emergency plumber to arrive, shutting off the water supply main can prevent extensive flooding and worsening of water damage. So how do you shut off your main water supply and in what situations should you do this? Below we look at the safest and most efficient ways to shut off your main water line in the event of a plumbing emergency.

water pressure gauge

Shutting Off Supply To One Fixture

If you are having an issue with just one plumbing fixture, such as a broken faucet, toilet, or washing machine, the easiest fix is to shut off the water to that individual fixture. This can allow you to stop water flow or flooding from one fixture while maintaining a water supply to the other functioning outlets in your home. For plumbing issues affecting only one outlet, this is the best solution.

Check for a valve connected to the water inlet pipe attached to your plumbing fixture. This is usually located below or behind the fixture. Some appliances that have both a hot and cold water supply and may have two valves to shut off the hot and cold water respectively. Turning off these valves can help to stop flooding and water damage at a single fixture while maintaining supply to the rest of the home.

Shutting Off The Main Water Supply

If your problem is more widespread or you can’t pinpoint a single fixture that’s causing issues, you may need to shut off the main water line. The first step to shutting off your main water line is identifying where the valve is. If you happen to have a plumber visit your home for a repair or maintenance, it can be helpful to ask a professional plumber to identify the location of the main water valve in your home. In warmer climates, the water supply valve is often found outside, near your water meter, a garden faucet, or the boundary of your home. In colder climates and in units, the main water supply valve is often under the kitchen or laundry sink, the basement, or in a utility room. Identifying the main water supply valve is often the most confusing aspect of this process.

Once you have identified the valve you can turn it off in the event of a plumbing emergency or burst water main pipe. The main water valve can be turned right to shut off the water supply. In some cases, an older water supply valve may have only a knob or a nut for turning, so a wrench may be required to shut it off.

These instructions should allow you to shut off the water supply to your home. Keep in mind however that there will still be water inside your plumbing system that may take some time to drain out. Knowing how to shut off your water supply can help you buy precious time and prevent water damage while waiting for the expert assistance of your local emergency plumber and rooter.