Livermore, CA
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68ºBackflow Prevention
Water distributions systems are designed so that water flows in one direction from the treatment plant to the customer. Backflow is the undesired reverse flow of liquids in a water service line, such as flow from an irrigation line into a building’s domestic drinking water line.
Federal and State laws require water purveyors to protect community water systems from contamination due to cross-connections and backflows into the system. Livermore Municipal Water monitors over 2,000 backflows each year to ensure the safety and welfare of our customers and the quality of our drinking water. A vital link in this effort is the Livermore Municipal Water Cross-Connection Control and Backflow Prevention Programs. Livermore Municipal Water requires the use of backflow prevention devices at certain types of facilities to prevent contamination of the water supply.
Backflow assemblies are an integral part of the Livermore Municipal Water Backflow Prevention and Cross Connection Control Programs. They help ensure that no contaminants of any kind (chemicals, debris, recycled water, etc.) enter the potable water system. Backflow assemblies are owned by each customer and regulated by the State Water Resource Control Board (SWRCB) through the water utility. While it is primarily business customers who require these devices, some residential properties need them as well.
Types of Backflow Devices
A reduced pressure principal (RP) assembly offers sophisticated protection against back siphonage and back pressure in domestic water service lines. The RP device has a relief valve located between two check valves. The relief valve will discharge water should either check valve fail. The RP device requires annual testing.
A double-check detector backflow prevention assembly (DCDA) is used on main fire service lines. A DCDA consists of two backflow devices, one on the main line and the other on a bypass line. The bypass line device contains a small meter for detecting water use. All fire service backflow devices are required to be tested annually to ensure proper working order.
Annual Testing
Livermore Municipal Water requires annual testing of backflow prevention devices installed on water service lines for domestic use, irrigation, and fire service lines. Backflow devices on fire service lines also are required to have meters that are inspected regularly to ensure proper working order.
Livermore Municipal Water sends notices to customers when their backflow prevention devices are due for testing. The notice includes test report due dates and a list of backflow assemblies with serial numbers and locations.
Only Livermore Municipal Water-approved backflow testers are allowed to test in our service area. Please refer to our list of approved backflow testers to make an appointment to have your backflow tested.
Becoming a Livermore Municipal Water-Approved Backflow Tester
To be included on Livermore Municipal Water’s approved backflow testers directory, each tester must turn in their City of Livermore business license, backflow tester wall certificate, wallet card, and test kit calibration certificates annually. Testers are required to have their test gauge equipment calibrated annually and submit proof of calibration. Approved testers must be certified by the American Water Works Association (AWWA), the Northern California Backflow Prevention Association (NCBPA), or a similar certification program that is approved by Livermore Municipal Water.
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