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What to Do After a Water Main Break

February 9, 2022
Illustration showing steps to take after a water main break.

San Antonio homeowners may experience plumbing issues that originate from outside their homes. If there is a water main break, this emergency can affect residences in your neighborhood, cause a street to flood, and/or shoot water straight up into the air. You may also see silt, sludge, and debris pouring out of your faucets and fixtures.

During a water main break, pressure in the line causes water to continuously flow upward from a hole or crack in the pipe. The incident can occur due to changing ground and air temperatures. The ground contracts when it’s cold and expands when it’s hot, putting pressure on the pipes below; a leak can form at any weak point.

Water main breaks can be fixed in a few hours. But there are a few steps to ensure your safety and prevent property damage, which include:

Follow Any Boil Water Advisories

If the water department suspects water supplies are contaminated, they will issue a boil water order. That’s because dirt, debris, and potential pathogens may be entering the pipe at the break point. When a boil water warning is issued, boil any water used for drinking, cooking, or brushing your teeth (or that’s otherwise ingested) for at least 1 minute. You can often safely clean, shower, or do laundry with un-boiled water.

 Flush Your Home Plumbing Lines

Water utilities recommend flushing cold water lines. You can do this by:

  • Opening a large tap: A bathtub is ideal because it’s a larger tap than a sink, so can discharge debris and particles more quickly without clogging. Smaller taps, like faucets and toilets, can become clogged and require repairs. As you run the bathtub tap, you may hear hissing or spitting, meaning there’s air in the line; allow the water to run until it is clear and free of air bubbles.
  • Start From Top to Bottom: Open the highest tap that doesn’t have an aerator. Then open other faucets one at a time, starting at the highest floor. For one-story dwellings, begin at the fixture closest to where water enters your home. Run the faucets for five to 15 minutes or until the water is clear and air-free, then turn off taps in reverse, from the lowest to highest one. If it’s still not clear, wait 30 minutes and flush the cold-water lines again.

 Precautions to Take

A water main break can cause damage within your home. If one occurs in your area:

  • Check for toilet leaks, as changes in water pressure can shift the toilet flapper.
  • Don’t flush cold water through a refrigerator line or other tap with a filter; sediment can clog it.
  • Don’t turn on the hot water tap; sediment that’s entered the pipe may be drawn into the hot water heater tank.

 How to Protect Your Plumbing and Appliances

After you flush your pipes, run the water from your hot water tank. Turn off the water when it turns cold. Wait an hour and repeat this process. For refrigerators with in-door water dispensers, run the dispenser for a few minutes, then replace the filter. Also change the filter in a water filtration system if you have one. Dishwashers and washing machines should be run through two empty and water-only cycles, and then a third cycle with detergent.

Once the water main is repaired, water may exit your fixtures with a reddish discoloration. Follow our steps for running cold water to flush iron compounds out of the system.

 Add a Water Main Filtration System

Installing a water main filtration system can keep debris, sediment, sand, and rust from the municipal water supply out of your home. It helps improve water quality and can reduce the risk of damage and excess wear.

Check Your Homeowner’s Insurance Policy

Your city or municipality owns the water main but won’t cover the cost of damage caused by a water main break. Check if your homeowner’s insurance policy covers “clean water” damage. If not, inquire about adding a special policy rider that does.

Schedule Water Main Repair with Elmer’s Air Conditioning & Plumbing

Our certified plumbers assist any homeowner in the San Antonio area who is experiencing water main issues. If you’ve recently had a water main break, we can quickly find the root cause and fix it. We take on jobs of any size and recommend the best options for restoring your water service. In addition, we provide high-quality piping and repiping, bathroom and kitchen plumbing, slab leak repair, water heater repair, sewer cleaning, and camera line inspection services. To get started, schedule an appointment online or call/text 210-570-1717 today!

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