Taking Measures to Reduce Stagnant Water After a Prolonged Shutdown

Flushing Building Water Systems

Flushing water lines might not be high on a checklist for a business reopening in a building that has been empty or underused. But it should be.

Flushing usually occurs automatically as people run faucets, drink from water fountains and flush toilets. If activity hasn’t occurred for several weeks, it’s important to flush the pipes to move out the older water and bring in fresh water.

Pinellas County’s drinking water meets or surpasses the water quality standards established by the Safe Drinking Water Act and regulated by the U.S. Environmental Protection Agency (EPA). In fact, the disinfectant that’s part of the drinking water treatment kills viruses—including COVID-19. Clean water is key in maintaining good health through hydration and in stopping the spread of the virus through handwashing.

However, the quality of the water that’s been sitting in the internal plumbing of an empty or underused building can decline. This creates taste and odor issues, discolored water and potentially even bacteria growth.

Flushing water lines is a simple process. Pinellas County Utilities offers guidance for business owners to help them maintain good water quality inside their facilities.

Who Should Flush

Any business, office building, school or other facility that has been empty or underused should flush their water lines. After the water flows through a meter, building owners are responsible for maintaining interior water quality.

What to Flush

All appliances that use water like faucets, drinking water fountains, kitchen sprayers, dishwashers, ice makers, toilets, hot water heaters, spas and decorative water features.

How to Flush

  • Disconnect filters on any point-of-entry devices. Remove and clean faucet aerators.
  • Find the cold-water faucet closest to where the water enters the building. Then, turn on this faucet and all cold-water faucets in kitchens and bathrooms. Let cold water flow for approximately 20 minutes depending on the size of your building.
  • Flush all appliances that use water. Run an empty load in the dishwasher and let water flow through drinking water fountains and kitchen sink sprayers. Empty the ice from ice-maker bins. Run and discard two additional batches of ice for each ice maker.
  • Flush all toilets, spas and water features like fountains. Follow manufacturers’ instructions for filter replacement.
  • Increase the temperature on the hot water heater to at least 140 degrees for 30 minutes. Turn on the hot water tap closest to the water heater and in kitchens and bathrooms. Let water flow long enough to drain the water heater.
Flushing Building Water Systems - Water Fountain
Flushing Building Water Systems - Sinks
Flushing Building Water Systems - Faucet

Contact Pinellas County Utilities

Phone: (727) 464-4000
Email: custsrv@pinellascounty.org
Address: 14 South Fort Harrison Ave., Clearwater, FL 33756


For more information addressing water quality challenges related to coronavirus (COVID-19), view the Environmental Protection Agency’s guide for disinfection, cleaning and more.