State Water Board explains needs assessment criteria used to flag failing and at‑risk water systems

Dan Wang, needs‑assessment unit supervisor in the Division of Drinking Water, told the SAFER advisory group on Feb. 12 that the board’s annual needs assessment identifies failing and at‑risk community water systems using multiple, data‑driven categories and indicators. The assessment, he said, is designed to target state funding and technical assistance where systems cannot reliably provide safe drinking water.

The assessment uses six failure categories — health‑based contaminant violations with open enforcement actions; secondary maximum contaminant level exceedances tied to enforcement; bacteriological (E. coli) violations; treatment‑technique violations; monitoring and reporting failures; and source‑capacity or outage violations — and supplements those with a proactive risk assessment that scores systems on four dimensions: water quality, water quantity (source availability), affordability, and technical/managerial/financial (TMF) capacity. "We're here to help the remaining 2%," Dan said, noting that 98% of Californians receive drinking water that meets regulatory standards while roughly 2% remain served by systems that do not consistently meet those standards.

Under the risk assessment, staff assign thresholds and weights to multiple indicators (for example, trends toward an MCL, presence of emerging contaminants, lack of interties, single‑source systems, drought/shortage scores from Department of Water Resources, socioeconomic burden and extreme water bills, and metrics such as operating ratio and days cash on hand). Dan told the group that the criteria and indicators have been revised through public workshops and that changes (additions or removals of indicators) follow a public process.

Advisory members pressed on affordability as a concern. Adam Rausch (GHD, technical assistance provider) asked whether high bills or financial stress can itself trigger a failing classification. Dan and other staff said there is currently no regulatory standard that makes affordability alone a failing classification; SB 1188 and ongoing rulemaking will address financial‑capacity regulations over the coming years. Dan emphasized the needs assessment is primarily used to inform prioritization for SAFER funding rather than to dictate local decisions about operations.

The presentation included a discussion of state small systems and domestic wells, which are not uniformly regulated by the board; where monitoring data are lacking, staff use proxies such as the source of water and available regional data to approximate risk.

Next steps: the needs‑assessment results feed into the annual Fund Expenditure Plan (FEP) and advisory‑group input; staff encouraged members to raise additional questions and noted links to supporting materials and the 2024 needs‑assessment documentation would be shared with the group.