1. (a) If a cross-connection between an onsite potable water system and an onsite nonpotable water system (treated or untreated) is discovered, the responsible entity must conduct the following procedures immediately:

   1. (1) Notify the local jurisdiction, the public water system, and building tenants and/or residents of the cross-connection no later than 24-hours upon discovery;
   2. (2) Cease delivery of onsite treated nonpotable water to the building and use area premises, and drain the onsite treated nonpotable water riser, if applicable;
   3. (3) Shut down the potable water service to the building and its premises at the user's service connection. User's service connection is as defined in the State Board's Cross-Connection Control Policy Handbook adopted pursuant to section 116407 of the Health and Safety Code;
   4. (4) Uncover and disconnect the cross-connection;
   5. (5) Perform another visual inspection, in accordance with section 60702, and cross-connection test, in accordance with section 60704;
   6. (6) Chlorinate the onsite potable water system with 50 parts-per-million (ppm) chlorine for 24 hours; and
   7. (7) Flush the onsite potable water system after 24 hours and perform a standard bacteriological test acceptable to the local jurisdiction. Where test results are acceptable to the local jurisdiction, the onsite potable water system can be permitted to be recharged.
2. (b) Prior to restarting delivery of onsite treated nonpotable water, the responsible entity must investigate the cause of the cross-connection and complete corrective actions. The responsible entity must submit a report describing the incident and completed corrective actions to the local jurisdiction for the local jurisdiction's approval prior to restarting OTNWS operations.

Note: Authority cited: Sections 13558 and 13558.1, Water Code; and Sections 116271 and 116350, Health and Safety Code. Reference: Sections 13558 and 13558.1, Water Code.

History

1. New section filed 4-22-2026; operative 4-22-2026 pursuant to Water Code section 13558(f) (Register 2026, No. 17).