What is Legionella, and where is it found?
- Legionella bacteria naturally exist in the environment, usually in freshwater environments. The bacteria grow best in warm water (77-113 F), most commonly found in water sources such as hot and cold water taps, hot water tanks, and water in air conditioning systems. They have also been found in misting systems, decorative fountains, and whirlpool spas.
What is Legionnaires' disease? - Legionnaires' disease is a bacterial disease that may cause respiratory illness or pneumonia.
Potential reasons for Legionella growth are generally related to the design or operation of the water system, such as but not limited to:
- Sections of no or low-water flow in the piping system (chlorine residual reduces over time)
- Water softeners (these types of systems can reduce chlorine residual)
- Water heaters (store water above 140 F and circulation systems above 120 F)
What is the City's role?
- The City is responsible for potable water quality delivered to customers up to the water meter. Water past the meter belongs to the customer and is outside the city's control and responsibility.
- The City maintained an average level of 0.9 mg/L free chlorine residual in calendar year 2023 (see our Water Quality Report)
- The City samples chlorine residual throughout the water distribution system at least twice a month. If chlorine residual is found at a level of 0.2 ppm or below, the City will take corrective actions to bring that residual to at least 0.3 ppm or higher.
Additional Resources:
(FAQ11852)
