COVID-19 and Facility Water Systems Management

Federal, state, and local COVID-19 policies are likely affecting water systems at facilities. Facility managers should consider how changes in building use will affect water management plans, and then make changes to those plans in order to maintain biological safety. Specifically, low use or no use of potable water and cooling tower systems will negatively impact the quality of water in these systems, which will likely result in the need for remediation and re-commissioning before the building or space is reopened to occupants. In addition, if any unused or low use building or wing is converted to use for high-risk or COVID-19 patients, the safety of the water systems needs to be verified before patients are allowed to enter that space. These systems must be monitored and maintained thereafter. General recommendations are as follows:

Domestic Cold and Hot Water Systems and Water Fixtures

During times of low or no use in a building or wing, water remains in the system much longer than usual. Disinfectant levels (chlorine) will fall too low, bacteria can grow, and biofilms can form on the internal surfaces. In addition, the water will rise to nearly room temperature in Domestic Cold systems and can fall too low in Domestic Hot systems. Temperatures above 67 deg F and below 124 deg F allow Legionella bacteria to grow. To avoid these problems, regular flushing of the Domestic Cold and Hot water distribution systems is recommended daily.

An alternative method for Domestic Hot water systems is to open the valve on the most distant fixture in the system and continuously bleed water through it 24 hours per day. All fixtures should be flushed a minimum of once per week. Flush fixtures after the distribution system is flushed so that water with adequate levels of disinfectant (chlorine) will flow through each fixture.

Drinking Fountains

Either flush with plenty of water daily or at least every weekday using a water supply with adequate disinfectant levels OR shut off the water supply completely and don’t allow any use. If shut off, each unit will need to be cleaned according to the manufacturer’s instructions before being used again for drinking.

Water Softeners

When little or no water is used, bacteria and biofilm can grow inside the softener and foul the resin. Fouling will reduce the life and capacity of the resin and will later consume chlorine which will result in water leaving the softener with little or no disinfectant protection. Either run plenty of water through each softener daily OR manually regenerate it every few days.

An alternative to manual regeneration is to program the unit to regenerate several times per week on specific days. If regeneration is currently based on gallons of use, then re-program the unit to regenerate based on time.

Cooling Towers

Low load or no load for an extended period will result in growth of bacteria, biofilm, and possibly Legionella bacteria. If chillers will remain off and a cooling tower is not needed, then shut it down and drain the cooling tower to prevent these problems. If a cooling tower is still needed for low or intermittent load, keep the tower water circulating, continuously bleed water from the tower at a low rate, and continue to regularly apply adequate biocide(s)/chlorine to maintain control of biological growth.

Re-purposing an Unused or Low-use Wing or Building for High-Risk or COVID-19 Patients

Before patients are allowed to enter the wing or building, the biological safety of the domestic cold, domestic hot, and all cooling tower water systems must be achieved and then verified by testing. Disinfectant (chlorine in the case of domestic water) levels must be high enough, water temperatures must be in the appropriate safe range, and Legionella and other bacteria must be reduced to safe levels. Thereafter, systems must be monitored, and biological safety must be maintained. In this case we recommend using a water management consultant.


Due to the governmental stay at home order, we are currently not conducting in-person site visits. However, we are available by phone or e-mail to answer questions or assist you with problems:

  • Jeremy Overmann: or (217) 333-5903
  • Angie DiAscro: or (217) 300-3882
  • Cameron Dillion: or (217) 244-0179
  • Jenn Tapuaiga: or (217) 300-0084
  • Mike Springman: or (618) 468-2780
To schedule a future site assessment, please fill out the form here.