State Water Board receives expert panel’s nitrogen management recommendations, outlines regional workshop path forward

The State Water Resources Control Board on June 16 heard final recommendations from a 10‑member expert panel convened to advise the irrigated lands regulatory program on managing nitrogen from agriculture.

Panel chair Daniel Geisler, an extension specialist at UC Davis, told the board the panel recommends focusing on the A‑minus‑R metric (nitrogen applied minus nitrogen removed) using a three‑year rolling average and that regional water boards should set region‑specific targets and limits. "We recommend implementing increasingly strict targets and limits using an iterative approach," Geisler said, adding the panel supports complementary tools including soil nitrate testing, models in data‑rich areas, and discount factors for organic amendments.

Why it matters: Panel members said A‑minus‑R more directly approximates leachable nitrogen and therefore groundwater risk than A/R efficiency ratios, while recognizing data gaps for many crops and farm types. The panel urged an ‘‘all‑hands’’ strategy of outreach, technical assistance and applied research to help growers reach interim goals before stricter limits are applied.

Panel and staff recommendations: Annalisa Kihara (Assistant Deputy Director, Division of Water Quality) and staff described a three‑bin approach for implementing panel recommendations: near‑term improvements the board can make under current authorities (standardizing data reporting), mid‑term actions that might require an information order (e.g., increased soil testing), and longer‑term regulatory actions (e.g., allowing regionally set A‑minus‑R limits, discount factors, and alternative reporting for certain farm types). Chief deputy Karen Mogas told the board she recommends a public workshop with regional boards to present regional implementation realities before statewide regulatory changes are proposed.

Public comment and split views: More than 20 oral commenters emphasized divergent priorities. Community and environmental groups urged the board to move quickly to adopt enforceable numeric limits in regions where data support them and pointed to health and drinking‑water harms. Corinne Gibson (Leadership Council for Justice and Accountability) said scientific evidence supports interim limits and urged action where data exist.

Agriculture and small‑farm advocates pressed for regional flexibility and alternative reporting pathways. Sarah Lopez (Central Coast Water Quality Preservation Inc.) warned that the Central Coast revised order’s proposed receiving‑water numeric limits would leave most of her coalition’s members unable to comply and asked the board to adopt the expert panel’s recommendation that initial limits be set where 80–90% of growers can meet them.

Technical details and clarifications: Geisler explained that A and R are estimates and recommended averaging over multiple years to limit year‑to‑year volatility. The panel suggested an initial cap of about 200 pounds per acre for nitrogen in irrigation water in high‑nitrate regions as a transitional approach and supported discount factors for plant‑available nitrogen from compost based on C:N ratios.

Board next steps: Staff said they will: (1) develop a schedule for regional workshops to gather implementation inputs from regional boards and stakeholders; (2) categorize ("bin") the panel’s recommendations into items achievable now, items needing information orders or guidance, and items requiring formal regulatory amendments; and (3) return to the board with proposed paths and timelines, aiming to bring a detailed proposal for board consideration in the coming months.

Votes at a glance: The agenda included procedural roll calls adopting board minutes and two uncontested items. No formal statewide regulatory action was taken on the panel recommendations at this meeting; staff moved to proceed with workshops and to develop regulatory options for future board consideration.

What’s next: Staff will coordinate regional workshops to better define implementable options and to identify data‑gaps and costs. Stakeholders recommended the board clarify interim expectations for coalitions and alternative reporting approaches for nurseries and small diversified farms before any region adopts strict new limits.

Ending: The board received the expert panel report and public testimony and directed staff to pursue a public, multi‑region process to refine how the panel’s technical recommendations translate into implementable policy and regulatory proposals.