1. (a) All indoor and outdoor use areas where onsite treated nonpotable water is accessible to the public or common areas must be posted with permanent and durable signs that are visible to the public, in a size no less than 4 inches high by 8 inches wide, and that include the following wording: “CAUTION: ONSITE TREATED NONPOTABLE WATER -- DO NOT DRINK.” Each sign must contain letters of a highly visible color on a purple or other contrasting color background. Each sign must display an international symbol similar to that shown in figure 60310-A.
2. (b) A sign must be installed in each publicly accessible or common area restroom of commercial, mixed-use, and multifamily buildings using onsite nonpotable treated water for water closets, urinals, or both. Each sign must contain letters of a highly visible color on a purple or other contrasting color background. The location and appearance of each sign must be such that the sign is visible and legible to users and must be approved by the local jurisdiction. Each sign must contain the following text: “TO CONSERVE WATER, THIS BUILDING USES ONSITE TREATED NONPOTABLE WATER TO FLUSH TOILETS AND URINALS.”
3. (c) Where tank-type toilets are flushed with onsite treated nonpotable water, a permanent sign (made from material such as plastic or stainless steel) must be installed inside the tank to warn that the water within the tank is not a suitable emergency drinking water supply. The sign must include the following language: “CAUTION: ONSITE TREATED NONPOTABLE WATER -- DO NOT DRINK.”
4. (d) A sign must be installed in each publicly accessible or common area laundry facility of commercial, mixed-use, and multifamily buildings using onsite nonpotable treated water for clothes washing machines. Each sign must contain letters of a highly visible color on a purple or other contrasting color background. The location and appearance of each sign must be such that the sign is visible and legible to users and must be approved by the local jurisdiction. Each sign must contain the following text: “TO CONSERVE WATER, THIS BUILDING USES ONSITE TREATED NONPOTABLE WATER FOR CLOTHES WASHING.”
5. (e) Each equipment room containing OTNWS equipment must have a sign posted in a location that is visible to anyone working on or near OTNWS equipment. Each sign must contain letters that are at least 1 inch (25.4 mm) in height of a highly visible color on a purple or other contrasting color background: “CAUTION: ONSITE TREATED NONPOTABLE WATER, DO NOT DRINK. DO NOT CONNECT TO DRINKING WATER SYSTEM. NOTICE: CONTACT BUILDING MANAGEMENT BEFORE PERFORMING ANY WORK ON THIS WATER SYSTEM.”
6. (f) The local jurisdiction may accept alternative signage and wording, provided that the responsible entity demonstrates to the local jurisdiction that the alternative approach will ensure an equivalent degree of public notification.

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).