Emergency Services

How to Shut Off Your Home’s Main Water Supply

shutting off water valve header

In case of a plumbing emergency, it’s always a good idea to know how to turn off your home’s main water supply. A burst pipe, sewage backup, or a ruptured line can cause a lot of damage to your home and cost you thousands in water damage.

By knowing how to shut off your home’s water supply, you’ll help the situation with damage control and allow yourself to call plumbing professionals to come and help assess the damage.

How Water Enters Your Home

Before jumping into how to shut your home’s water supply, it’s important to know how water enters your home. We often don’t think about our plumbing systems, but it is one of the most important parts of your home. It’s what allows clean drinking water to enter your home and takes contaminated water out.

Having clean water in your home is something that we can all appreciate. The reason we can have clean water is thanks to a little piece of equipment called a backflow valve. Backflow valves are double-flow tubes that are built to stop any contaminated water from reaching your faucet. Without it, contaminated water would enter your home.

How Does A Backflow Preventer Work?

When water enters your home it comes from your main water supply, and the water should only flow in one direction. However, when pressure is lost, water can get pushed back creating backflow.

Normally, because the pressure is optimized for your home plumbing system, contaminants will move down through pipes and into the ground, while the clean waters will go up into your home. However, when pressure changes your clean water can become contaminated. The backflow valve will prevent that contaminated water from reaching your home, by keeping the water in your main supply flowing in one direction.

How to Find Your Backflow Valve?

If you have a plumbing emergency, such as a flood, you’ll need to turn off your backflow valve, you can locate it in a few different places depending on state regulations.

Most homes will have their backflow valve on the outside of the house near their sprinkler system or water meter, to turn it off you may need a special key to be able to turn it. Depending on the climate you can also find it in your basement near your water heater.

How to Turn Off Your Main Water Supply?

If you need to shut off your main water supply you simply need to locate the valve and turn it clockwise until the water stops flowing (you should be able to hear it stop). For a visual guide, check out our infographic below on how to shut off the main water supply to a home.

Contamination RulesRegulations

When it comes to your water and contaminations each city has its own regulations. Each city decides on how they’re going to test and clean their water. Sometimes regulations require a small air gap between the delivery point of water and local storage or use in the home. This is built to help control backflow due to high pressures. Other regulations control the quality of water and methods to avoid contamination, for more information about Utah’s drinking water, check out our blog here.

These regulations and standards are set in place to protect public health by limiting contaminant levels in drinking water. To find general rules about contamination, you can check out the EPA’s drinking water requirements.

Need a Plumber?

If you have any concerns regarding your home’s plumbing system and the quality of your water supply, please feel free to contact Shamrock Plumbing. We provide services to customers along the Wasatch Front.

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