Building Reopening Guidance - Preventing Water Quality Problems

Preparing Your Building for Reopening

Many large buildings that normally housed office workers, food establishments, manufacturing, and other businesses have been closed. The water has remained stagnant in the building’s plumbing during the past two months. The stagnant water in these buildings might increase the risk of bacterial growth, including coliform bacteria and Legionella, in the plumbing. Furthermore, when the stagnant water is in contact with plumbing (e.g., pipes, fixtures, etc.) for extended periods of time, elevated concentrations of metals, including lead and copper, may develop. As a preventive measure, Maryland Department of the Environment’s (MDE) Water Supply Program strongly recommends that the plumbing in each building be flushed prior to the reopening of the business.

The recommended flushing will help to remove potential bacteria, metals, disinfection by-products, and other contaminants that may have developed as a result of low or no use of water. These simple preventive actions will help protect the building occupants from unnecessary exposure to water quality problems that may be unsafe for consumption.

Please contact the Water Supply Program at (410) 537-3702 or water.supply@maryland.gov if you have any questions regarding this reminder.

Thank you for staying vigilant during the pandemic and continuing to serve your community with the highest quality of drinking water.

Building Flushing Guidance:

  1. Purdue University Center for Plumbing Safety
    Flushing plans
    https://engineering.purdue.edu/PlumbingSafety/resources/flushing-plans

  2.  Environmental Science, Policy, and Research Institute
    Flushing guidance
    https://esprinstitute.org/wp-content/uploads/2020/04/FINAL_Coronavirus-Building-Flushing-Guidance-20200403-rev-1.pdf

    Reducing risk to staff who are performing flushing

    https://esprinstitute.org/wp-content/uploads/2020/05/FINAL_Reducing-Risk-to-Staff-Flushing-Buildings-20200501.pdf

Other Resources:

  1. The United States Centers for Disease Control (CDC) Guidance for Reopening Buildings After Prolonged Shutdown or Reduced Operation
    https://www.cdc.gov/coronavirus/2019-ncov/php/building-water-system.html

  2. Association of State Drinking Water Administrators (ASDWA) COVID-19 Resources for Building Water Systems
    https://www.asdwa.org/2020/04/13/covid-19-resources-for-building-water-systems/

  3. The Maryland Department of the Environment (MDE) Water Supply Program COVID-19 Public Water System Compliance Challenges and Helpful Links
    https://mde.maryland.gov/programs/Water/water_supply/Pages/WhatsNew.aspx

  4. EPA Water Utility Resources for the COVID-19 Pandemic
    https://www.epa.gov/coronavirus/water-utility-resources-covid-19-pandemic