State Water Board holds hearing on proposed on-site nonpotable reuse rules; public commenters press for operator certification and Title 22 alignment

Shirley Rossella, senior staff with the Division of Drinking Water at the State Water Resources Control Board, outlined proposed statewide regulations for on-site treatment and reuse of nonpotable water at a public hearing and invited public comment on the draft. The rules would set risk‑based water quality standards, monitoring and reporting requirements, cross‑connection controls and treatment‑train options for building‑scale systems used for nonpotable indoor and outdoor purposes.

The regulations respond to Senate Bill 966 (2018) and codified direction in the California Water Code to adopt standards for on-site reuse. Rossella told attendees, “The proposed regulations will establish criteria for on-site treatment of non potable water for non potable reuse.” She said the State Water Board developed the rules to be “protective of public health” and noted the board cannot itself permit local installations: “We do not have the authority to permit on-site reuse systems.”

The draft regulation text presented by staff includes: risk‑based pathogen log reduction targets (LRTs) derived from quantitative microbial risk assessment; preset “pathogen control” treatment trains (examples include membrane bioreactors,…