Cross Connection Control & Backflow Prevention

Sweetwater Authority is committed to providing safe and reliable drinking water to our customers. An important part of the Authority’s water quality program is its Cross Connection Control and Backflow Prevention Program, which is required by Federal and State law.

Cross Connection: any actual or potential physical connection between a public water system, and any source of non-potable liquid, solid or gas that could contaminate or pollute the potable water supply by backflow. 

Backflow: the undesirable reversal of flow of fluids, chemicals, or any other foreign material into the public drinking water system. 

The two forms of backflow are:

Backsiphonage - usually caused by a loss of pressure in the drinking water system.
Backpressure - usually caused by pumps, piping system elevations, or thermal expansion from a heat source.

Backflow prevention assemblies stop backflow and prevent contaminants and pollutants from entering the drinking water system via cross connections. 

Installation of Approved Backflow Prevention Devices

The California Department of Public Health and the Authority’s Rules and Regulations require the installation of an approved backflow prevention device under the following (but not limited to) conditions: 

  • Residential Customers (Properties with an unapproved auxiliary water source, pump, fire sprinkler system, or any hazard that may contaminate the distribution system.)
  • Business, Commercial, Industrial, Landscape, and Agricultural Customers.
  • Apartments, Townhomes, and Condominium Complexes.
  • Fire Service Laterals, Gray Water Systems, Wells, Multi-story, and Multi-units.
Backflow devices shall be installed, repaired, or replaced by the customer as per Authority requirements.  All costs for installation, testing and maintenance are the responsibility of the customer. The California Department of Health Services requires backflow devices to be tested upon installation and annually thereafter. Testing must be completed by a certified tester approved by the Authority. 


For questions about the Authority’s Cross Connection Control and Backflow Prevention Program, call 619-420-1413 or email

SWA employee reading pressure gauge on backflow prevention assembly

An Authority Cross Connection Control Specialist uses a differential pressure gauge to certify a backflow prevention assembly.