By Jane Sooby
The Second Statewide Agricultural Expert Panel continued to deliberate on its charge questions during a Halloween meeting that featured at least two participants in costume.
In the spirit of the day, expert panelist Thomas Harter was dressed as a scarecrow and commenter Sarah Lopez of Preservation, Inc. was disguised as a bottle of ketchup.
CDFA Presentations
Secretary of Food and Agriculture Karen Ross kicked off presentations by providing an overview of programs offered by the California Dept. of Food and Agriculture (CDFA) that intersect with the Irrigated Lands Regulatory Program (ILRP). The expert panel has been convened to advise the State Water Board on specific aspects of the ILRP. Read an account of Ross’s presentation here.
Senior Environmental Scientist Natalie Jacuzzi then presented information on CDFA’s Fertilizer Research and Education Program (FREP). Jacuzzi, FREP’s new director, described the research that FREP has funded over the past 35 years. FREP’s grantmaking program is funded through fees paid to the program, and since 1991 it has funded 282 projects totaling $32.5 million. FREP has mostly funded nutrient management research, with irrigation management the second most common topic. Jacuzzi reported that funding outreach and education has been a focus over the past 10 years. The FREP database provides access to summaries and full reports on all 282 FREP-funded projects.
Turning her attention to FREP’s crop fertilization guidelines, Jacuzzi credited expert panel chair Daniel Geisseler’s lab with developing the guidelines, which translate the research into practical guidance for growers. Crop fertilization guidelines are available for the 28 crops grown on the most acreage in California. Six sets of guidelines have been translated into Spanish. The guides are updated when new research becomes available. The guidelines show nitrogen (N) uptake curves and nutrient needs of the crop at each developmental stage.
Jacuzzi described how FREP worked with University of California Agriculture and Natural Resources (UC ANR) to train Certified Crop Advisors (CCAs) to certify the irrigation and nutrient management plans (INMPs) required under the ILRP.
Through its Nutrient Irrigation Initiative, FREP has also trained 5,000 growers in the Central Coast region to adopt efficient irrigation and nutrient management practices and to certify their own INMPs. Jacuzzi reported that the program is expanding to Ventura County.
Scott Weeks, Senior Scientist in CDFA’s Office of Agricultural Resilience and Sustainability, next presented information on their incentives and technical assistance programs. Through CDFA’s suite of climate smart ag programs, CDFA has disbursed $675 million in grants, most of them awarded to growers to implement greenhouse-gas reducing practices. Weeks reported that these programs have resulted in removal of 30 million metric tons of carbon dioxide equivalents, which is equal to removing 6.5 million cars from the road. He provided details on the Healthy Soils Program, the Alternative Manure Management Program, the State Water Efficiency and Enhancement Program (SWEEP), and the Organic Transition Program.
Weeks also described the Water Efficiency Technical Assistance Grant Program, which evaluates growers’ irrigation systems and makes recommendations for improving their efficiency. It offers pump efficiency testing and to date has supported over 1,300 field pump tests. The program also offers irrigation efficiency trainings that are tailored to local needs, with language support offered in Spanish, Hmong, Punjabi, and Mandarin.
In another collaboration with UC ANR, the Climate Smart Agriculture Joint Program has provided additional technical assistance to growers for adopting climate smart practices. So far the program has supported 1,325 growers in 24 counties.
Weeks ended his presentation by linking CDFA’s efforts to California’s commitment to developing nature-based solutions to transition the state to 100% clean energy and carbon neutrality by 2045. Key to the strategy is bringing 3.1 million farm acres under healthy soils management.
Expert panelists then had the opportunity to ask questions about CDFA’s presentations. Ruth Dahlquist-Willard, Interim Director, UC Sustainable Agriculture Research and Education Program, noted that there is no funding for technical assistance to help growers comply with ILRP. Ross acknowledged that CDFA could take a “bigger integrated approach on this.”
State Water Board Staff Presentation
The expert panel next heard a presentation from State Water Board Chief Deputy Director Karen Mogus, who reviewed the water boards’ mission and authority and the regulatory development process, acknowledging “the bleed between technical evaluation and policy.” She reviewed the Porter-Cologne Water Quality Control Act that created state authority to protect water quality and regulate waste discharges to land and water. Mogus outlined the non-point source policy adopted in 2004, which defines non-point source pollution as discharges not traceable to a specific, single discharge point but from diffuse sources such as runoff from agricultural lands, urban areas, and forestry operations.
Mogus next described how state water regulations are developed. The expert panel makes science-based recommendations to the State Water Board, which is tasked with turning them into policy using a public and transparent process. The State Water Board considers the economic impacts and feasibility of implementing proposed regulations.
Mogus proceeded to define what the state means by an “enforceable limit,” commenting “It’s a number, you need to comply with it and will get a violation if you don’t comply with it.” She noted that any targets or limits need to have a “scientific basis and rationale that links the limit to protecting beneficial uses and getting to the goal of protecting groundwater.”
Mogus stated that the State Water Board will determine if enforceable limits will be implemented, and confirmed that enforceability is the difference between a target and a limit. She also noted that the first agricultural expert panel decided not to implement limits but instead recommended that farmers report data on nitrogen applied (A) and nitrogen removed (R) and its derived value A/R.
Mogus said that the limits put forth in the Central Coast region’s Agricultural Order 4.0 went beyond the authority granted by the State Water Board in its precedential Eastern San Joaquin order, and portions of Ag Order 4.0 were remanded back to the regional board to align it with the state’s precedents. In its remand order, the State Water Board also created the Second Statewide Agricultural Expert Panel. “And here we are!” said Mogus.
Central Coast Regional Water Board Staff Presentation
Next, Elaine Sahl, Irrigated Lands Program Manager with the Central Coast Regional Water Board, walked panelists through an example demonstrating how the regional board calculates ranch-level A-R for a farm that produces three crops annually. Nitrogen (N) applied (A) is the sum of N from fertilizers, compost, organic fertilizers, and irrigation water. The discounts for compost and organic fertilizer applications included in Ag Order 4.0 were remanded by the State Water Board. Sahl pointed out that the regional board had worked closely with agricultural researchers to make sure these discounts were grounded in science.
To calculate the N removed (R) side of the equation, N removed from crop harvest is added to N sequestered in woody growth. Ag Order 4.0 also offered credits for N scavenged by winter cover crops, N removed via a “quantifiable treatment method” such as a bioreactor, and N removed by other means; however, the State Water Board remanded these credits. Sahl stated they believe that “significant scientific evidence” supports these alternative compliance pathways.
Sahl then pivoted to presenting water quality data that had been requested by the expert panel. She demonstrated the Region 3 (Central Coast) Groundwater Quality Dashboard and how to evaluate the water quality data for agricultural wells and domestic wells. She said that the regional board is developing interactive maps that will show well data, INMP data, aquifer risk mapping, and statewide crop mapping.
Sahl showed regional water quality data that indicate significant exceedances of the 10 mg/L maximum contaminant level (MCL) for N in drinking water in over 50% of samples.
Sahl concluded by stating that this is why “it’s so important that in the Central Coast region we proceed with limits and ultimately reduce their N discharge. We have been doing outreach and education for over 20 years and still see increased N discharges.”
Sahl’s presentation was followed by panelist questions. Dahlquist-Willard asked a series of questions about how small-scale diversified farms report data. Sahl clarified that growers report A and R by crop and that the regional water board performs the calculations on that data to calculate ranch-level data. Dahlquist-Willard followed up with a question about what technical assistance is offered to farmers. Sahl responded that most of it is provided by the third party for the region, Preservation, Inc.
Expert panelist Ali Montazar, Irrigation and Water Management Advisor, UC Cooperative Extension Imperial County, who has consistently drawn attention to the unique conditions of desert agriculture, asked about how the regulations might apply to the desert region, where the sole source of irrigation water is surface water from the Colorado River because there is no usable groundwater available. Additionally, surface N discharges in the region are drained into the Salton Sea and do not impact groundwater. Montazar asked how targets and limits could be set under those conditions. Mogus from the State Water Board responded, “To the degree there are sources of drinking water impacted by discharges from agriculture, there would be a basis for targets or limits. If there are no sources of drinking water, it stands to reason they wouldn’t need to set limits.”
Expert panelist Thomas Harter, Distinguished Professor of Subsurface Hydrology, UC Davis, asked Mogus, “Porter-Cologne guides you to protect drinking water. Why is there even a question about whether there should be a target or limit? If your job is to protect water quality, what’s the role of a non-enforceable target? What’s the rationale for having targets rather than limits when the mandate from the legislature is to meet a certain standard?” Mogus requested time to think about this question.
In response to a question by expert panel chair Daniel Geisseler, Assistant Cooperative Extension Specialist, Department of Land, Air and Water Resources, UC Davis, about whether growers have the option to report ranch-level data on N applications rather than crop-level data, Sahl stated that “we feel we need crop-specific information because we’re finding a lot of our small diversified farms are still growing high risk crops for N discharges.” Sahl indicated that regional staff feel that crop-level data is necessary to see if growers are making progress to reduce N discharges.
After the lunch break, Mogus invited Darrin Polhemus, Deputy Director for the State Water Board’s Division of Drinking Water, to clarify the first expert panel’s thought process about setting targets and limits. “We realized at that time limits were not reachable,” said Polhemus. “That expert panel gave us the A/R ratio as something that would be doable to compare different operations.”
Expert Panel Logistics
Next, meeting moderator Sam Magill addressed logistics including the panel schedule. Magill proposed that the January 14, 2026 final meeting be a listening session for a draft report that will be released prior to it and that the final panel meeting be rescheduled for late February or early March, when the report would be finalized. Panel members voted to accept the revised panel schedule.
Magil requested that the panel prioritize its list of additional information requested.
Then, Magill clarified language in three of the panel’s charge questions.
- He explained that the “factors” mentioned in question 3 referred to items raised in the first expert panel’s report Appendix C on factors that need to be accounted for when calculating N mass balance.
- He explained that the “tables” referred to in question 5 refer to INMP Summary Tables that were provided to panelists.
- He noted that Harter had brought up question 9 regarding exemptions and asked Mogus to clarify that the panel can offer technical bases for operations’ impact on groundwater quality to be de minimis and thus potentially exempt from regulation.
Harter stated that rice growers successfully advocated for a separate agricultural order for rice because intensive well testing showed N contamination was not a problem and asked if there are other areas where this is the case. Patrick Pulupa, Executive Officer of the Central Valley Water Board, stated that “it took a lot for rice to demonstrate to the board that they’re not experiencing nutrient losses that would impact water quality.” Pulupa said he didn’t know if other groups would be willing to undertake the expense of developing a separate ag order.
Panel Discussion
The conversation then moved to discussion of draft responses to questions 1 and 2 written by panelists Richard Smith, Vegetable Crop Production & Weed Science Farm Advisor, UC Cooperative Extension Monterey County – Emeritus, and Hannah Waterhouse, Assistant Professor of Agroecology and Watershed Ecology, Environmental Studies Department, UC Santa Cruz. Much of the conversation centered around the panel’s basis for recommending targets versus limits and how a 3-year rolling average would be calculated when different crops are grown on a field.
They also discussed the different reporting requirements in the Central Valley and Central Coast regions and the relative level of anonymization in the regions. Sahl explained that data is not anonymized in the Central Coast region. Growers report on the ranch level a list of crops, number of acres for each, and A and R for each crop. In the Central Valley, growers report data by individual fields and crops.
Pulupa acknowledged that the Central Valley has a “very complicated reporting structure” that reports data back at a township level. “You will never have information on a field-specific basis,” he stated, noting that the data shown in the tables is tied to APNs (Assessor’s Parcel Numbers) rather than individual fields. He explained that this approach is practical for conducting a “landscape-level regulatory program” overseeing non-point source discharges that cannot be tracked back to a specific field.
Geisseler again raised concern about how the 3-year rolling average of A/R is used to identify outliers in the Central Valley region, pointing out that outliers are only calculated for a crop grown in the same field for 3 years or by the same manager, so if a grower rotates their crops or the field is managed by a different farmer over that time period, the field will never appear to be an outlier. He said, “We need to develop a system where every field has an equal opportunity to be included in the 3-year average.”
Harter asked how the Central Coast region handles situations when 3 crops are grown in a year with one crop straddling the calendar year. Sahl responded that they have built a solution into the GeoTracker system that automatically transfers N applied the previous year for a crop harvested the following year.
Panelist Ngodoo Atume, SGMA Technical Assistance for Small Farms Coordinator, UC Sustainable Agriculture Research and Education Program, suggested that rather than solely considering targets, the panel might want to explore setting N application limits and A-R targets with limits being a long-term goal and targets an interim goal. Montazar also supported the idea of setting both limits and targets, as was done in Ag Order 4.0.
Responding to draft text stating that A-R together with hydrogeological models be used to set discharge targets, Harter gave an overview of how the hydrogeological model is used in the Central Valley region to analyze grower-reported data to estimate potential nitrate discharge from the root zone and set township-level groundwater protection targets. He noted that this approach may not be “the gold standard for every place in California,” particularly in the Central Coast region where a water-protective target may not be agronomically feasible.
Public Comment
The meeting ended with a round of public comment. Once more, Jake Dialesandro and Iris Stewart-Frey of Santa Clara University presented data from the Central Valley region, this time showing that high nitrate levels in groundwater are strongly correlated with irrigated lands but not with concentrated animal feeding operations (CAFOs). They also noted that the chances of groundwater nitrate exceeding the MCL were 3.3 times higher for communities with 60% or more Latino/a residents than for communities with lower proportions of Latino/a residents. They argued that this disparate impact on Latino/a communities demonstrates that it’s important to set N limits sooner rather than later.
Ramy Colfer, who oversees research and development at True Organic Products, the largest organic fertilizer manufacturer in the United States, presented data showing that organic fertilizers are fundamentally different from conventional fertilizers because organic N must first be mineralized by soil microorganisms before it’s available to plants. While 100% of applied synthetic N is plant-available, only 40-60% of applied organic N is plant-available. “If you don’t take that into account,” he said, “you’re disproportionately penalizing organic farmers.”
Ramy cited research out of UC-Davis that predicts the amount of N a grower can get from an organic fertilizer given its C:N ratio.
Colfer noted that organic fertilizers also contain carbon, which feeds microbes and builds soil organic matter, reducing the risk of nutrient runoff and leaching. Colfer pointed out that other state agencies including the Air Resources Board and CDFA have included organic agriculture in their climate strategies.
Colfer offered suggested responses to the panel’s question 7 regarding discount factors and concluded that organic farming furthers the State Water Board’s environmental goals and should be supported by including scientifically-based correction factors for organic inputs in the agricultural orders.
Other commenters weighed in on the impact of groundwater nitrate contamination on communities and the need to set numeric limits on N discharges.
Sarah Lopez, Preservation Inc., noted that calibrating hydrogeologic models was a challenge in the Central Coast region and that most groundwater basins in the region don’t have existing models.
The expert panel continues to convene in working group meetings. Upcoming meetings are Nov. 19, Dec. 5, and Dec. 12, 2025. Visit the expert panel website under Announcements for information on how to sign up to join the meeting and to comment .
