As Maryland prepares to reopen businesses and offices according to the ‘Maryland Strong: Roadmap to Recovery‘ plan developed by the Hogan Administration in response to COVID-19, and as employees, staff, and visitors of various establishments are getting ready to return, many buildings that were either closed or partially closed due to the pandemic may experience water quality problems due to stagnant water in the premise plumbing. Our water system serves many large buildings that may have been empty for several weeks recently. As such, we would like you to be aware of some simple measures that can improve the quality of the drinking water in your buildings as normal operations resume. Below are links that provide guidance and information on how to flush a building’s stagnant water.
For many large buildings that normally housed office workers, food establishments, manufacturing, and other businesses, 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 Water Supply Program strongly recommends that the plumbing in each building be flushed prior to the reopening of the business.
The recommended flushing (please see links below) 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.
Important Documents:
Maintaining or Restoring Water Quality in Buildings with Low or No Use
Restoring Water Quality in Buildings for Reopening
Building Flushing Guidance:
Purdue University Center for Plumbing Safety – Flushing Plans
Environmental Science, Policy, and Research Institute – Flushing Guidance
Reducing Risk to Staff Who are Performing Flushing
Other Resources: