State Water Board technical staff told the advisory group that phase 1c of the wastewater needs assessment has produced a statewide facilities inventory to be assessed for inadequacy and risk, naming 2,657 systems across all nine regional boards.

Dakota Keane, a geologist at the Office of Water Programs, summarized the data collection effort and the resulting facilities list, saying the effort produced a “first-of-its-kind methodology to determine whether or not a given facility is actually treating domestic sanitation related wastewater.” The inventory combines facilities regulated under WDRs (discharge to land), permitted collection systems and NPDES systems (discharges to surface waters).

The inventory draws on many sources, staff said: regional board data, engineering reports for state-funded projects, a UC ANR baseline survey and sewershed boundaries provided by the California Association of Sanitation Agencies (CASA). Staff also compiled geospatial datasets to assess possible groundwater impacts and to inform solutions modeling. The inventory excludes facilities that do not process domestic sanitary waste (for example, commercial-only or non-sanitary reuse sites), and staff said private residences will be handled through a separate unsewered analysis.

Staff acknowledged remaining data gaps — notably for on-site systems — and said some on-site/system-level assessment work will be handled in phase 1e (solutions and cost assessment) or phase 1d (groundwater impacts), with plans to gather more complete data in subsequent steps.

Timetable and next steps: staff said phase 1 report sections are under internal review and the draft will be shared with advisory members by early fall. Office hours and quarterly advisory meetings will continue through phase 2 (July 2025–June 2027) to allow data validation and focused technical engagement.

Community and partner roles: staff thanked regional boards and CASA for data contributions and emphasized that regional validation will be a part of the process before any public lists are released.