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Must Knows This Week State Water Board’s Tule Scrutiny Goes Beyond the Exclusion Denial — Local Allocation Methodologies on the Line

Following our prior coverage of the State Water Board’s denial of remaining Tule Subbasin exclusion requests, Porterville Irrigation District GSA staff reported new detail: at the April 21 vote, state officials questioned the 34-year rolling precipitation average, how native sustainable yield numbers were derived, and how recharge credits are being treated — raising the possibility of future changes to how PID GSA structures its allocations and Basin Safe accounting. PID staff also noted that the State Water Board has given inconsistent guidance to individual callers on whether to include recharge water in GEARS submittals (Lower Tule excluded recharge from its filings), and cautioned that the scrutiny may force structural changes in coming years. Read More

Four Valley GSAs Explore Kaweah-Tule Banking — With Southern California as Key Partner

Mid-Kaweah GSA detailed early feasibility discussions alongside Lower Tule River, Pixley, and Greater Kaweah to build a massive groundwater bank with SWP/CVP contractors, with Southern California agencies discussed as the key example partner. The conceptual partnership would import surplus wet- and average-year SWP/CVP surface water to recharge local aquifers, generating a negotiated “leave-behind” volume to permanently benefit local growers and SGMA compliance — return water to partners would primarily come from west-side surface water, with groundwater recovery treated as an ultimate backstop to protect local wells. Read More

Kings and Kaweah Growers Should Plan for Compressed Irrigation Runs

Building on prior coverage of the record-low snowpack and Kings River runoff outlook, Kings County Water District reported the coordinated Kings River irrigation run is planned to start May 15 and last about 75 days, with the April 1 water supply number in the mid-40% range — projections that ran 50-55 days at the prior meeting have shrunk further. Nearby, Kaweah Delta Water Conservation District reviewed a Kaweah River outlook around 51% if no additional inflow materializes, citing the latest Airborne Snow Observatory flight showing peak runoff already past and only 41,000 acre-feet of snowpack remaining. Read More

Mid-Kaweah Moves Toward Mandatory Well Registration — Miss the Proposed Deadline, Could Lose Allocations

Mid-Kaweah GSA committee members voted to recommend mandatory registration for ag and industrial wells generally pumping more than 2 acre-feet per year, with October 31, 2026 discussed as the target deadline; growers who fail to register could be zeroed out of Tier 1 and Tier 2 allocations and face possible monthly per-well fees. Staff is pushing a 15-25 minute “fast-track” office process where the GSA pulls well-completion reports from the county on the grower’s behalf, with personalized non-compliance notices to follow. Read More

Trends in the Valley

Fee Authority Across Districts Is Splitting Between Prop 218 and Prop 26 Pathways.

Colusa Groundwater Authority GSA is exploring a per-well fee under Prop 26 (no vote) vs Prop 218 majority protest pathways for SGMA Sections 10730 / 10730.2. Pleasant Valley GSA is preparing an Engineer’s Report under Prop 218 that would establish a proposed extraction-fee ceiling of approximately $50/acre-foot. Santa Clara Valley Water District is moving 6.6%–9.4% groundwater rate increases through its annual water-charge public hearing process, with adoption scheduled May 12.

Two Subbasins Show Modeling and Consulting Costs Becoming Budget Pressure Points

Northern Delta-Mendota Region Management Committee faces a cost-split dispute over a $500,000 subbasin model calibration that threatens to stall the modeling effort entirely; the committee voted to support pursuing a complementary U.S. Bureau of Reclamation WaterSMART Applied Science grant of up to $400,000 (with a 25–50% non-Federal cost share, applications due July 8, 2026) if cost share is agreed. Cuyama Basin GSA cut roughly $650,000 from its draft FY 2026-27 budget by deferring most model-improvement studies and a $150,000 historical land-use update, and separately restructured its Standing Advisory Committee meetings to cap technical consultant participation at 3 hours and limit legal counsel to brief updates — dropping per-meeting costs from ~$16,000 to ~$9,600.

About WaterOne: 

WaterOne is a Fresno-based water management firm serving Central Valley growers, founded by a team from Stanford that combines agricultural expertise with AI engineering. The team offers easy-to-adapt water management tools designed for SGMA. The company actively monitors GSA and irrigation district board meetings, maintaining a database of rule changes for each district while working directly with growers across the Central Valley. You can access their updates on major meetings at GSAs, Irrigation Districts, and State Board from their GSA Database from https://gsa.waterone.ai

About the Team:

Ryo Takanashi is Co-Founder & Chief Product Officer at WaterOne. He brings extensive expertise in commodity trading and agricultural engineering. As the youngest Chief Corn Trader for Japan’s largest commercial importer, Ryo managed 20% of the country’s corn imports while stationed in Kansas and Minneapolis. With an Urban Engineering background, he combines technical infrastructure knowledge with hands-on commodity market experience that required constant analysis of crop conditions, yield forecasts, and supply chain logistics. He holds MS-MBA from Stanford.

Tomo Kumahira is Co-Founder & CEO of WaterOne. Prior to starting WaterOne, Tomo managed one of Africa’s largest agro-forestry operations as CFO, partnering with small-scale 30,000 farmers and covering 40% of commercial afforestation in Kenya. He began his career in natural resources investment at Mitsubishi Corporation. Tomo holds MS-MBA from Stanford (Knight-Hennessy Scholar and Rotary Global Scholar).

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