Commercial, existing agricultural, industrial, institutional, and multi-family water service customers are required to have backflow prevention assemblies.

• The installation of these assemblies may be required by any building or property improvement and/or an inspection by a Cross Connection Control Specialist.

• Backflow prevention assemblies are required to be tested upon installation, anytime the assembly is required, replaced or relocated, and on an annual basis.

• The testing must be completed by a San Bernardino County Backflow Assembly Tester. Here's a list of companies that test in the district.