By Jane Sooby
The Second Statewide Agricultural Expert Panel, convened by the State Water Resources Control Board (State Water Board) to review data collected so far by the Irrigated Lands Regulatory Program (ILRP) on nitrogen applied (A) and nitrogen removed (R), met on Monday, October 13 to start discussing the specific questions they’ve been assigned to answer.
In a process chaired by University of California Cooperative Extension (UCCE) nutrient management specialist Daniel Geisseler, panelists first introduced themselves then commented on what additional information they would like to consider. They discussed how to tackle writing their report under the constraints of California’s open meeting law, the Bagley-Keene Open Meeting Act which requires all deliberations be conducted at public meetings. They began discussing the first of nine “charge questions” before them. And they heard a brief round of public comment.
Additional Information Requested by Panelists
The panel has been given quite a bit of data already, including recommendations of the first expert panel convened in 2014; California Crop Fertilization Guidelines published by the California Dept. of Food and Agriculture; past agricultural orders issued by the regional and state water boards; scientific articles; presentations made at the two-day kickoff meeting and the first public listening session; public comments submitted; and a State Water Board analysis of available Irrigation and Nitrogen Management Plan data.
Two panelists expressed interest in following up with Eric Morgan, a presenter at the public listening session who had shared nitrogen (N) carryover data from vegetable crops in the Central Coast region and expressed concern that gaseous nitrous oxide losses are not accounted for in the A-R model.
Ali Montazar, UCCE Irrigation and Water Management Advisor in San Diego and Imperial Counties, requested input from an agricultural economist, “given that we are talking about one of the biggest agricultural economies in the world.” He also requested data from a cattle and dairy expert on how they impact nitrates in groundwater.
Richard Smith, emeritus vegetable and weed science farm advisor from Monterey County, requested the latest research on the role of high-carbon amendments in immobilizing nutrients in the fall. He also suggested that the panel hear about managing the A side of the equation through a robust nitrogen testing program.
Ruth Dahlquist-Willard, interim director of the University of California’s Sustainable Agriculture and Research Program, requested hearing more from growers in the Central Valley and Central Coast regions, specifically from nursery producers whose system of growing plants in pots seems to differ greatly from irrigated systems that grow plants in the ground. She also suggested hearing from someone in the Central Valley’s Kings River Watershed Coalition about their experience with implementing the alternative N reporting pathway for small-scale, highly diversified growers that was set forth in the State Water Board’s precedential Eastern San Joaquin order in 2018 (and approved for eligible growers in the Kings River region by the Central Valley regional board’s Executive Officer in 2023).
University of California Davis subsurface hydrology professor Thomas Harter expressed his opinion that “The question of targets versus limits is a policy question more than a scientific question” and requested that an expert in administrative law clarify which of these are backed by penalties. He noted that fair regulation requires that penalties be tied to enforceability and wondered about the relative merits of a “stick” approach versus an incentives approach to enforcement. Dahlquist-Willard also expressed interest in these two approaches and suggested the panel be informed about other regulatory programs that have been widely adopted by growers. Harter also called for information on how exemptions may be built into the regulations.
Panel mediator Sam Magill reminded members that economic considerations had specifically been excluded from their charge questions. He noted that the State Water Board would use the expert panel’s findings to modify the regulatory program and the panel won’t need to do that. Chief Deputy Director of the State Water Board Karen Mogus also emphasized that they’d like the panel to focus on technical issues as much as possible. Still, panel members expressed that they felt it important to understand the economic implications of their recommendations.
Writing the Report Under Bagley-Keene Restrictions
One panelist suggested that a subgroup be created to discuss question 9 (regarding possible exemptions or alternative compliance pathways for the ILRP) and to report their conclusions to the full group. Chair Geisseler clarified that because of California’s open meetings law, no subgroups can meet and all discussions must take place at public meetings. State Water Board staff stated that panelists cannot work on a shared Google document or discuss the panel’s work if they encounter each other outside of the expert panel meetings.
Geisseler suggested that panelists split into two-person teams that will work alone on their assigned questions then send their drafts to water board staff, who would compile all materials for group review. Rather than select the two-person teams at this meeting, the group decided to create the teams at a future date.
Other Concepts Considered by Expert Panel Members
One-size-fits-all: Many panelists expressed that, due to the diversity of California’s cropping systems, a one-size-fits-all regulation isn’t likely to be feasible. Some also noted that one-size-fits-all doesn’t make sense from a systems analysis perspective. Montazar brought up many examples of how agriculture in the desert differs from agriculture in the Central Valley and Central Coast regions, such as the wide diversity of crops grown including alfalfa, which typically removes more N from the soil than is applied, and the fact that growers must leach their fields annually to push salts below the root zone and don’t see nutrient carryover between crops.
Michael Cahn, irrigation and water resource UCCE advisor in Monterey County, observed that an economically viable N application threshold may be far from a water protective level and mused whether targets and limits should be focused on locations where there is high nitrate in the groundwater.
Harter presented a novel image of wells shown from an underground perspective with the landscape appearing as the ceiling and wells appearing as pipes hanging down from the ceiling. The graphic illustrates that the source area for a well’s water can extend over an area anywhere from 1-10 miles, resulting in a given well‘s water originating from various locations and being of various ages. (Can you say “non-point source” without saying “non-point source”?) He suggested that crop- or season-specific variability are “only part of the puzzle” and recommended taking 3-year rolling averages on a farm or field basis with an emphasis on larger farms as opposed to “really tiny parcels.”
Crop-specific limits: In response to a panelist’s comment about possibly creating “crop-specific limits,” Tess Dunham, attorney with Kahn, Soares, and Conaway who works with industrial agriculture on water policy, later observed during public comment that fertilizer discharge or application limits are not a requirement of California’s Porter Cologne Water Quality Control Act and that language in question 1 is “leading” in suggesting that limits are the only regulatory option.
Other panelists weighed in on the concept of “crop-specific limits” with most of them rejecting the idea largely due to lack of data. Cahn noted that the Central Coast region’s Ag Order 4.0 is not crop-specific and cannot be because of double or triple cropping in a single field annually.
Establish thresholds and focus enforcement on outliers: Geisseler floated the idea and shared slides demonstrating an approach that graphs A-R by percent of fields at that level. The threshold would be set at the level achieved by 80% of acres, with enforcement focused on the top 20%, the reasoning being “You need to do better because 80% of your neighbors can make it work.” As more growers optimize their A-R value, the 80% value would decrease over time.
The Challenge of Intensive Vegetable Production in the Central Coast Region: However, Smith stated that data from the Central Coast shows the complete opposite of what Geisseler showed and that the percentage of growers in the Central Coast region achieving the proposed target of A-R = 50 lb N/acre was only 20% in 2023 while 80% were achieving 300 lb N/acre. The group referred back to data presented by Sarah Lopez, Executive Director of the Central Coast region’s third party, Preservation, Inc., at day 2 of the panel’s kickoff meeting. (Note: the 50 lb N/acre target was set forth in the Central Coast region’s Ag Order 4.0 as a target to be achieved by the year 2051.)
Cahn proceeded to show a series of slides that walked through an A-R calculation for double-cropped vegetables in the Salinas Valley. He noted that R (nitrogen removed) is often less than half of the N that the crop takes up in a season because of large amounts of crop residues remaining after harvest, with the average A-R for a romaine lettuce-broccoli rotation being 352 lb N/acre. He also pointed to the need to consider rolling 3-year averages to account for year-to-year variation and nutrient carryover between crop years.
Cahn’s presentation shifted to best practices including accounting for all forms of N applied including that in irrigation water and optimizing irrigation management. He said that by reducing fertilizer use, growers could get A-R down to around 285-300 lb N/acre. “We could use the approach of looking at outliers,” he said, “but once you get growers in this situation, where do you go from there?” Cahn suggested that these A-R levels are what is “agronomically possible” in the Central Coast region and stated in response to a question that adding a cover crop to the system could get A-R closer to 200.
After deciding to continue discussion of question 1 and attempt to get through question 4 at the next working group meeting, the meeting transitioned to a brief round of public comment that focused mostly on technical details. Of note, Mary Hamilton, Central Coast Water Board’s Environmental Program Manager, addressed the issues of enforceability and flexibility and stated that the regional board tried to build flexibility into Ag Order 4.0 through escalating levels of consequences for non-compliance. She noted that the civil penalties described by Sarah Lopez of Preservation, Inc. at the Oct. 1 listening session as an “operation-ending consequence” were only imposed after years of trying to work with a “recalcitrant” grower.
Next Steps
The expert panel will resume its discussions at the second working group meeting scheduled for Wednesday, October 22, 3-6 pm. The meeting will be held in person in Sacramento and online. Spanish translation will be provided. Advance registration is required. Click here for the agenda and click here to register.
