Multifamily, commercial, and/or industrial facilities, along with properties with an auxiliary water supply and parcels with irrigation meters in the district's service area, are required to have a backflow prevention assemblies.
- The installation of these assemblies may be required through the plan check process and/or an inspection by a cross-connection control specialist.
- The backflow prevention assemblies are required to be tested upon installation, on an annual basis and anytime the assembly is repaired, replaced or relocated.
- The testing must be done by a certified backflow prevention assembly tester appearing on the District's list. Click here for the list of approved backflow assembly testers or call the Cross-Connection Division at 909-987-2591
- Customers will receive an annual testing notification from the District.
Standard Drawings for Backflow Assembly
Please contact the Cross-Connection Division if you have any questions.