Through the Cross Connection Control program, the Water Division coordinates the planning, installation, and maintenance of backflow devices.
CROSS CONNECTION CONTROL
Technology has made it possible to deliver safe drinking water of high quality to our customers. To assure safe water, it is essential that a physical cross-connection is eliminated. If this is impractical, protection by installation of an approved backflow-prevention assembly becomes necessary.
The two most common types of backflow assemblies required by the City are the Reduced Pressure Principle (RPP) and the Double Check. There are other types, but these two offer the most resiliency for backflow prevention.
Each year, the City administers the testing of all backflow preventers that are installed. Any RPP device that fails the required test is also repaired by qualified testing agencies or Water Division employees. Any device that is tested, and determined beyond repair, must be replaced by the owner. Number of back-flow prevention devices installed in the City as of 5/18/2012: 8,500
DEFINITION OF WORDS USED IN CROSS CONNECTION CONTROL
Backflow: reversal of the normal flow of water caused by either backpressure or backsiphonage.
Backpressure: flow of water or other liquids, mixtures or substances under pressure into the city water supply.
Backsiphonage: flow of water or other liquids mixtures or substances into the city water supply caused by the reduction of pressure in the city water supply system.
Backflow Prevention Assembly: an approved assembly or means designed to prevent backflow.
Cross Connection: any unprotected actual or potential connection or structural arrangement between a water system and any other source or system through which it is possible to introduce into any part of the city water system contamination or pollution.