Expert panel leans on regional boards for initial nitrogen targets and backstops, urges technical assistance

Panel chair Daniel Geisler and members of the State Water Resources Control Board’s agricultural expert panel spent the bulk of the working-group meeting debating whether the panel should recommend statewide enforceable fertilizer limits or defer to regional boards to set "targets/limits." Panelists repeatedly emphasized regional variability and called for technical assistance alongside any numeric benchmarks.

The discussion opened when Thomas Harder, a cooperative extension professor, suggested using the wording "targets/limits" across the draft so the panel would not be taken as choosing one regulatory regime over another. Harder said the panel "agrees that there's a point at which end discharges to groundwater are excessive, and regional boards should be able to set initial targets limits that all growers should be able to meet within a reasonable time frame, 3 to 5 years." The panel debated whether to identify a specific percentile and Harder and others proposed setting an initial backstop at a high percentile of regional a-minus-r data (an example discussed was the 80th or 90th percentile) while leaving exact metric choice and procedure to each regional board.

Why it matters: panelists argued regional variability in soils, climate and cropping means a single statewide numeric limit would be infeasible and could produce perverse outcomes. Thomas and others said region-driven metrics—supported by region-specific models or discount factors—allow tailoring while protecting groundwater. The panel repeatedly flagged the need to pair any initial targets/limits with technical assistance so growers can reasonably comply.

Points of contention: several panelists raised the concern that hard limits can create a "ceiling" effect, where regulated parties aim only to fall just below the limit rather than continuing long-term improvements. As Thomas put it, experience from Region 5 suggests "when you set a limit, people just end up going right below the limit, rather than actually moving further," a dynamic the panel said should be considered in design and evaluation. Some public commenters pressed for stronger, enforceable limits; Tess Dunham, representing Central Valley interests, said the Central Valley’s Nitrate Control Program already embeds enforceable milestones and a removal-of-exception backstop, and argued that in that context additional statewide limits may be unnecessary.

What the panel directed: the group agreed to retain language that regional boards should be able to set initial numeric backstops informed by local a-minus-r (or equivalent) data, and to call out an initial implementation period (panel discussion referenced 3–5 years as an achievable compliance window). The panel also agreed to explicitly state that some regions have already set approaches (for example Regions 3 and 5) and that the report should emphasize procedures to avoid unintended consequences and to include an iterative evaluation process and exceptions protocol (to be detailed elsewhere in the report).

Quotes from the meeting: Thomas Harder: "The panel agrees that there's a point at which end discharges to groundwater are excessive, and regional boards should be able to set initial targets limits that all growers should be able to meet within a reasonable time frame, 3 to 5 years." Public commenter Tess Dunham: "There is no need for limits in the Central Valley when you consider that we have this backstop." Public commenter Kaya Rivers urged the panel to "recommend that the largest contributors are addressed as such," calling for interim limits or backstops for the highest dischargers.

Next steps: Daniel Geisler will incorporate today's discussion into a cleaned draft of the report. Panelists asked staff to ensure the text clarifies whether specific recommendations imply targets, limits, or both, and to add discussion of iterative evaluation and technical assistance in the relevant sections. The panel will review a cleaned draft before it is released for public comment.

Ending: The panel did not adopt a single statewide numeric limit; instead it favored a regionally tailored approach that provides regional boards authority to set initial numeric backstops, coupled with technical assistance and iterative evaluation to limit unintended consequences.