1506.5 Water Pressure. On-site treated non-potable gray

water systems supplying water to water closets, urinals, and trap primers shall be capable of delivering not less than 15 pounds-force per square inch (psi) (103 kPa) residual pressure at the highest and most remote outlet served. Where the

TABLE 1505.16 MINIMUM RECLAIMED (RECYCLED) WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

DESCRIPTION MINIMUM FREQUENCY*

Inspect and clean filters and screens, and replace (where necessary). [Every 3 months.]

Inspect pumps and verify operation. After initial installation and every 12 months thereafter.

Inspect valves and verify operation. After initial installation and every 12 months thereafter.

Inspect pressure tanks and verify operation. After initial installation and every 12 months thereafter.

Clear debris from and inspect storage tanks, locking devices, and verify operation.

After initial installation and every 12 months thereafter.

Inspect caution labels and marking. After initial installation and every 12 months thereafter.

* Note: Frequency is as described in this table, or more frequently as required by manufacturer’s instructions and/or the Authority Having Jurisdiction.

322 2025 CALIFORNIA PLUMBING CODE

ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

1506.10.3 Deactivation and Drainage. The on-site treated nonpotable gray water system and the potable water system within the building shall be provided with the required appurtenances (e.g., valves, air/vacuum relief valves, etc.) to allow for deactivation or drainage as required for a cross-connection test in accordance with Section 1502.3.

1506.10.4 Near Underground Potable Water Pipe. On-site treated nonpotable gray water pipes shall be permitted to be run or laid in the same trench as potable water pipes with a 12 inch (305 mm) minimum vertical and horizontal separation where both pipe materials are approved for use within a building. Where piping materials do not meet this requirement the minimum separation shall be increased to 60 inches (1524 mm). The potable water piping shall be installed at an elevation above the on-site treated nonpotable gray water piping. 1506.10.5 Required Filters. A filter permitting the passage of particulates no larger than 100 microns (100 µm) shall be provided for on-site treated nonpotable gray water supplied to water closets, urinals, trap primers, and drip irrigation system s . 1506.10.6 Disinfection. Where the intended use of onsite treated nonpotable gray water requires disinfec- tion and/or other treatment, on-site treated nonpotable gray water shall be disinfected as needed to ensure the required water quality is obtained at the point of use. Where chlorine is used for disinfection or treatment, water shall be tested for residual chlorine in accordance with ASTM D1253.