Because of the potential for water in a private plumbing system to flow back into the public water system in some conditions, we require some locations and some equipment/facilities, such as irrigation systems and swimming pools, to have "backflow prevention" devices.
Backflows may occur when there is a decrease in pressure in one part of the public water system due to a water main leak, during firefighting operations drawing water from hydrant(s), etc.
Our backflow prevention program is designed to protect the public water supply from water that could become contaminated after it has passed through the OWASA system.
ABOVE: A backflow prevention device
Backflow prevention devices must be tested annually to make sure they are working properly.
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