As nonessential businesses reopen this week and bring employees and customers back, facility managers are being advised to take several steps before restarting their building's dormant water system.

Legionella, the bacteria that causes Legionnaires' disease, could be lurking in dormant water systems says William Rutchow, an environmental attorney with Ogletree Deakins, a labor and employment law firm with offices in Stamford.

"These dormant water systems can lead to an increased exposure to Legionella for several reasons, including lack of water circulation, and a temporary cessation of water treatment and water quality monitoring programs," Rutchow writes on Ogletree’s website.

Stagnant water can lead to the bacteria that causes Legionnaires' disease, a severe form of pneumonia, because it can result in lower levels of disinfectants such as chlorine.

Preventative Steps

CDC water system guidance for reopening recommends building owners and managers take these steps before restarting water systems:

  • Evaluate your system and devices and, if necessary, use the CDC's water management toolkit to develop an effective water management program
  • Set all water heaters to at least 120 degrees
  • Flush the entire water system
  • Clean all fountains and other decorative water features
  • Ensure cooling towers are cleaned and maintained
  • Ensure safety equipment, including sprinkler systems, eyewash stations, and safety showers, are cleaned and maintained
  • Regularly check water quality measures such as temperature, pH, and disinfectant levels


Rutchow notes that while OSHA has detailed information on Legionella on its website, there is no set standard for hazards associated with exposure to the bacteria.

"Rather OSHA addresses Legionella hazards through the General Duty Clause, which requires employers to furnish each employee with a place of employment that is 'free from recognized hazards that are causing or are likely to cause death or serious physical harm,'" he writes.

So employers with a water system that's been dormant due to a mandated COVID-19 closing would be wise to identify and assess any potential sources of Legionella risk before reopening, Rutchow says, then develop a management plan.

For  more information, contact CBIA's Phillip Montgomery (860.244.1982).

Filed Under: COVID-19, Safety

Leave a Reply

Your email address will not be published.