1502.3 Cross-Connection Inspection and Testing. An

initial visual inspection and initial cross-connection test shall be performed on both the potable and alternate water source systems before the initial operation of the alternate water source system. During an initial or subsequent cross-con- nection test, the potable and alternate water source system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection in accor dance with Section 1502.3.1 through Section 1502.3.3 .

310 2025 CALIFORNIA PLUMBING CODE

ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

1502.3.1 Visual System Inspection. Before commencing the cross-connection testing, a dual system inspection shall be conducted by the Authority Having Jurisdiction and other authorities having jurisdiction as follows:

(1) Meter locations of the alternate water source and potable water lines shall be checked to verify that no modifications were made and that no cross-con nections are visible.

(2) Pumps and equipment, equipment room signs and exposed piping in equipment room shall be checked.

(3) Valves shall be checked to ensure that the valve lock seals are still in place and intact. Valve control door signs shall be checked to verify that no signs have been removed.

1502.3.2 Cross-Connection Test. A cross-connec- tion test shall be performed in the presence of the Authority Having Jurisdiction or other authorities having jurisdiction to determine whether a cross-connection has occurred as follows:

(1) The potable water system shall be activated and pressurized. The alternate water source system shall be shut down, depressurized, and drained.

(2) The potable water system shall remain pressurized for a minimum period specified by the Authority Having Jurisdiction while the alternate water source system is empty. The minimum period the alternate water source system is to remain depressurized shall be determined on a case-by-case basis, taking into account the size and complexity of the potable and the alternate water source distribution systems, but in no case shall that period be less than 1 hour.

(3) The drain on the alternate water source system shall be checked for flow during the test and fixtures, potable and alternate water source, shall be tested and inspected for flow. Flow from an alternate water source system outlet indicates a cross-connection. No flow from a potable water outlet shall indicate that it is connected to the alternate water source sys tem.

(4) The potable water system shall then be depressurized and drained.

(5) The alternate water source system shall then be activated and pressurized. When an alternate water source is not available for the initial cross-connec- tion test, a temporary connection to a potable water supply shall be required. At the conclusion of the ini- tial cross-connection test, the temporary connection to the potable water supply shall be disconnected.

(6) The alternate water source system shall remain pressurized for a minimum period specified by the Authority Having Jurisdiction while the potable water system is empty. The minimum period the potable water system is to remain depressurized shall be determined on a case-by-case basis, but in no case shall that period be less than 1 hour.

(7) Fixtures, potable, and alternate water source shall be tested and inspected for flow. Flow from a potable water system outlet indicates a cross-connection. No flow from an alternate water source outlet will indicate that it is connected to the potable water system.

(8) The drain on the potable water system shall be checked for flow during the test and at the end of the

test.

(9) Where there is no flow detected in the fixtures which would indicate a cross-connection, the potable water system shall be repressurized. 1502.3.3 Discovery of Cross-Connection. If a cross-connection is discovered, the following procedure, in the presence of the Authority Having Jurisdiction, shall be activated immediately:

(1) Notify the Authority Having Jurisdiction of the cross connection.

( 2 ) The alternate water source piping to the building and its premises shall be shutdown at the meter, and the alternate water source riser shall be drained.

( 3 ) Potable water piping to the building and its prem- ises shall be shutdown at the meter.

( 4 ) The cross-connection shall be uncovered and disconnected.

( 5 ) The building and its premises shall be retested in accordance with Section 1502.3.1 and Section

1502.3.2.

( 6 ) The potable water system shall be chlorinated with 50 parts-per-million (ppm) chlorine for 24 hours.

( 7 ) The potable water system shall be flushed after 24 hours, and a standard bacteriological test shall be performed. Where test results are acceptable, the potable water system shall be permitted to be recharged.