Health & Saf. Code, § 116786

(a) Notwithstanding subdivision (b) of Section 116785, a local agency may, by ordinance, limit the availability, or prohibit the installation, of residential water softening or conditioning appliances that discharge to the community sewer system if the local agency makes all of the following findings and includes them in the ordinance:

(1) Limiting the availability, or prohibiting the installation, of the appliances is a necessary means of achieving compliance with waste discharge requirements issued by a California regional water quality control board. In determining a necessary means of achieving compliance, the local agency shall assess both of the following:

(A) The technological and economic feasibility of alternatives to the ordinance.

(B) The potential saline discharge reduction of the ordinance.

(2) The local agency has adopted and is enforcing regulatory requirements that limit the volumes and concentrations of saline discharges from nonresidential sources in the community waste disposal system to the extent technologically and economically feasible.

(b) Notwithstanding subdivision (b) of Section 116785, a local agency may, by ordinance, limit the availability, or prohibit the installation, of residential water softening or conditioning appliances that discharge to the community sewer system if the local agency makes all of the following findings and includes them in the ordinance:

(1) Limiting the availability, or prohibiting the installation, of the appliances is a necessary means of achieving compliance with the water reclamation requirements or the master reclamation permit issued by a California regional water quality control board. In determining a necessary means of achieving compliance, the local agency shall assess both of the following:

(A) The technological and economic feasibility of alternatives to the ordinance.

(B) The potential saline discharge reduction of the ordinance.

(2) The local agency has adopted, and is enforcing, regulatory requirements that limit the volumes and concentrations of saline discharges from nonresidential sources to the community waste disposal system to the extent technologically and economically feasible.

(c) Local agency findings shall be substantiated by an independent study of discharges from all sources of salinity, including, but not limited to, residential water softening or conditioning appliances, residential consumptive use, industrial and commercial discharges, and seawater or brackish water infiltration and inflow into the sewer collection system. The study shall quantify, to the greatest extent feasible, the total discharge from each source of salinity and identify remedial actions taken to reduce the discharge of salinity into the community sewer system from each source, to the extent technologically and economically feasible, to bring the local agency into compliance with waste discharge requirements, water reclamation requirements, or a master reclamation permit, prior to limiting or prohibiting the use of residential water softening or conditioning appliances.

(d) Any ordinance adopted pursuant to this section shall be prospective in nature and may not require the removal of residential water softening or conditioning appliances that are installed before the effective date of the ordinance.

(e) To comply with this section, any local agency described in subdivision (f) of Section 116780 is authorized to adopt an ordinance.

(f) This section shall become operative on January 1, 2003.