Clean public bathroom sinks and counter.

Preparing Your Building for Reopening after COVID-19 Shutdown

After several weeks or more of non-use, stagnant water in building plumbing can cause conditions that increase the risk for growth and spread of Legionella and other biofilm-associated bacteria. 

Ensure that your water system is safe to use after a prolonged building shutdown by flushing your water system as follows:

  • Flush hot and cold water through all points of use (e.g., showers, sink faucets)
  • Flushing may need to occur in segments (e.g., floors or individual rooms) due to facility size and water pressure. The purpose of building flushing is to replace all water inside building piping with fresh water.
  • Flush until the hot water reaches its maximum temperature
  • Flush until the cold water reaches a steady cool temperature

For more information, consult the information provided by the Centers for Disease Control and Prevention at: