The State Water Resources Control Board (via an advisory group meeting in October 2025) outlined Phase 2 work on a statewide Wastewater Needs Assessment that will map unsewered parcels, score systems and facilities for inadequacy and risk, match potential solutions and estimate costs, and produce a five-year roadmap for ongoing work.

Project staff said the workstream will rely on three technical components presented to the advisory group: a parcel-level unsewered model from the University of Massachusetts Amherst, a spatial inventory of permitted treatment and collection systems, and an inadequacy-and-risk scoring framework that will produce lists of systems and facilities classified as "inadequate" or "at risk." Ariana Hernandez, project manager at the UCLA Luskin Center for Innovation, told members that Phase 1 of the needs assessment is in internal review and is expected to be posted publicly "on or around October 31." She said Phase 2 will assign solutions and cost estimates and develop a roadmap extending beyond the 2027 contract period.

Why this matters: The assessment seeks to give state policymakers a consistent, statewide basis to identify wastewater systems requiring technical, administrative or financial interventions. The lists and cost estimates are intended to inform funding priorities, the project team said, though staff emphasized the limits of the current scope and data availability.

Key technical work, timelines and deliverables
- Unsewered mapping: Nelson DeLuis of UMass described a geospatial machine-learning model that will predict, at parcel scale, whether properties are sewered or unsewered. Deliverables will include parcel-scale maps and geospatial data to be shared with the Division of Water Quality and the Office of Water Programs.

- Spatial inventory of facilities: A separate effort will compile spatial boundaries or best-available locations for systems regulated under Waste Discharge Requirements (WDRs) and NPDES permits, as well as small sewage general order (SSGEO) systems and collection-system assets. Project staff said they will use available shapefiles from utilities, the EPA's sewershed mapping tool and address-matching where boundaries are not available.

- Inadequacy and risk assessments: Grace (staff) described a six-part approach: separate inadequacy and risk assessments for sewer systems and for WDR/NPDES facilities, yielding six assessment outputs. Risk categories include socioeconomic, operational, environmental and public-health variables. The team is finalizing thresholds and weights in October and said it will publish methods and hold multiple review rounds (regional boards, executive management, the advisory group) before finalizing lists for publication. The team expects to publish draft lists for review and a more final list for advisory review in spring 2026, with public posting to follow.

- Solutions and costs: The Office of Water Programs (OWP) summarized how the team will assign a set of high-level remedial actions for inadequate systems (targeted repairs, rehabilitation or replacement, connection to other systems, package plants, or administrative remedies such as technical assistance or contracted operations). Line-item capital costs and operation-and-maintenance (O&M) allowances will be derived from engineering reports, converted to a common-dollar year for net-present-value calculations, and adjusted by regional cost multipliers and contingencies. OWP said preliminary solutions-and-cost work will begin in April 2026 and that statewide aggregations will be presented in 2026 with final Phase 2 documentation in 2027.

- Septic (on-site) connection opportunities: The team will use UMass mapping to identify clusters of on-site treatment systems (OSTS) where connection to existing sewer or community-scale package plants may be feasible.

- Groundwater impacts assessment pulled back: Maureen (OWP) said the project will not pursue a statewide groundwater-nitrate scoring product within this contract. The team documented a proposed methodology (using GeoTracker nitrate data, parcel-based estimates and soil/climate indicators) and will include that write-up as a placeholder for future work. Maureen said stakeholders preferred a diagnostic, regionally tailored tool that would require more coordination and resources than available under the current scope, so the team will focus on the core Phase 2 deliverables.

- Funding gap and affordability analysis: The funding-gap analysis will mirror the drinking-water needs assessment method: total modeled solution costs will be compared to projected state funding available through the State Water Board (the team said it will not model local rates, facility revenues, or federal funding). The affordability component will estimate community ability to pay using median household income and poverty prevalence and will flag disadvantaged communities; the team said rate and charge data are not available statewide and so a full rate-impact affordability analysis is out of scope for this contract.

Advisory group feedback and coordination
Advisory members raised timing and review concerns and asked for earlier advisory review windows for lists that will identify inadequate facilities. Jared Voskal of the California Association of Sanitation Agencies asked for an earlier look before finalization; project staff said they plan to incorporate regional-board and executive-management review before delivering a near-final list to the advisory group. Several members urged close coordination with regional staff and permit specialists on how compliance designations (for example, the Significant Noncompliance designation) are applied to treatment facilities.

Decisions and near-term directions
- The project team stated it will discontinue work on a statewide groundwater impacts scoring product in Phase 2 and will document the proposed approach for others to pick up later.
- The team committed to publishing methods (including code on GitHub) for transparency and reproducibility and to a multi-step review process with regional boards and the advisory group before final publication of the inadequate/at-risk lists.

What the team asked of advisory members
Staff asked advisory members for feedback on the Phase 1 report by Oct. 29, 2025, and invited suggestions for additional data sources or local knowledge that could improve parcel mapping, spatial inventories and the risk/inadequacy thresholds. The team also announced recurring office hours (monthly, typically the last Tuesday) for informal questions and said the next full advisory meeting will be in January 2026.

Limitations and context
Staff repeatedly cautioned that many tasks depend on external review timelines, contract end-date constraints (the contract period runs through 2027), and data availability. The team said they will publish the inadequacy and at-risk lists ahead of the full Phase 2 report and that some elements (notably statewide groundwater scoring and full rate-based affordability analysis) are out of scope for this contract and will be candidates for the roadmap or future efforts.

Ending note
Advisory members and State Water Board leadership on the call emphasized the assessment's role in documenting statewide need and informing future funding priorities, while noting that the work will not itself create funding decisions. "While this group is not a decision-making body, your feedback plays an essential role in shaping the wastewater needs assessment's direction," Board Member Morgan said during the meeting.