WSSC Flushing Guidelines

After a Water Main Break Repair

After a water main break repair is completed in your area, flush your lines using the following steps. Run all cold water faucets for five minutes. Turn off your faucets in reverse order, from lowest to highest.  You should also flush your refrigerator’s water lines.

Flushing your water lines lowers the risk of potential contamination that is created whenever a water main is depressurized because of a break.  This is particularly important for people who have special health concerns because their immunity is compromised.

What to Do During and After a Boil Water Advisory

When water systems lose pressure there is an increased risk of contamination. Therefore, the WSSC recommends if you live in the affected area:

During a BWA

  • Boil water for drinking, making ice, washing dishes, brushing teeth and food preparation.
  • Water should be brought to a rolling boil for one minute and cooled before using.
  • Water for pets should be boiled and then cooled for their use.
  • Dispose of ice from your refrigerator’s ice maker. DO NOT USE.
  • Disinfect dishes by washing them in dishwashing machines that have a dry cycle or a final rinse that exceeds 113 degrees F for 20 minutes, 122 degrees F for five minutes or 162 degrees F for one minute.

After the Boil Water Advisory is Lifted – Flush Your System

WSSC asks customers who were under the Boil Water Advisory or who have experienced a water service disruption due to a water main break to take a few precautions.

Steps to Take

WSSC recommends you flush the cold water lines you use in your home or business.  We recommend you flush your taps as a precaution because of an increase in the number of water main breaks in our aging infrastructure.  It will cost you just pennies per faucet to take this important step.

We suggest running all cold water taps for five minutes.  If you have a single-lever faucet, set it to run the cold water.  Begin with the highest faucet in your home or business and then open the other faucets one at a time, moving from your highest floor to your lowest.

Customers and businesses should also dispose of any ice made since the precautionary Boil Water Advisory. The next three batches of ice should also be thrown out.  Ice maker containers should be wiped clean with a solution of two tablespoons bleach to one gallon of water.

If you still experience problems after performing the above procedures, or if you have any questions, please contact our Customer Emergency Call Center 24 hours a day, seven days a week at: (301)-206-40021-800-828-6439 or TTY (301)-206-8345.

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