Special to WaterWrights.net by WaterOne.ai

 WaterWrights.net is now sharing Weekly Updates in partnership with our friends at WaterOne.ai. We all know SGMA is evolving rapidly. And this is another step for us to keep everyone informed.

Must Knows This Week

Second-Lowest Snowpack on Record — Growers Looking at a 4-Week Delivery Window

DWR‘s April 1 snow survey came in at just 18% of statewide average — the second-lowest on record for that date, trailing only 2015 — and the effects are already hitting the Valley. Tulare Irrigation District reported Kaweah snowpack at 17% and told growers to plan for 4–5 weeks of surface water at 0.4–0.5 AF/acre, down from 6 weeks at 0.65 last summer. Lower Tule River Irrigation District projected 3–5 weeks depending on whether CVP Class 1 holds or drops to 85%, and Exeter Irrigation District is planning around 1.04 AF/acre at $325/acre under an assumed 85% allocation. Read More

Delta-Mendota Returns to DWR — Tule Remains on Probation, Hearing April 21

California Water Board unanimously returned the 760,000-acre Delta-Mendota Subbasin to DWR, praising its 23-GSA consolidated plan. Tule and Tulare Lake remain on probation — Pixley GSA estimates ~$2.3M in fees for Pixley alone ($20/AF on ~118,000 AF), with the full Tule Subbasin facing ~$12M; the hearing on exclusion requests is **Tuesday, April 21** (written comments due 12:00 noon Monday, April 20). In response, Pixley and Tri County Water Authority both approved joining an effort to consolidate ~13 GSAs into a single GSP — modeled after successful consolidations in Kern and Delta-Mendota. Read MoreSemitropic Penalties, Merced and McMullin Head to Prop 218 Votes

Semitropic Water Storage District finalized civil penalties of up to $500/AF for 2025 water budget exceedances, plus a $1,000 delinquency penalty. Merced Subbasin GSA adopted a maximum $15.11/acre annual charge across ~186,315 acres with a Prop 218 hearing set for June 15. And McMullin Area GSA launched a Prop 218 election for a $32.85/acre assessment to fund a ~$22M flood capture expansion — ballots mailed April 17, hearing June 3. Read More

Salinas Valley Estimates: Even Eliminating All Ag Pumping Won’t Stop Seawater Intrusion by 2040

Salinas Valley Basin GSA presented updated modeling showing that shutting off all agricultural pumping valley-wide still fails to meet seawater intrusion minimum thresholds by 2040. Illustrative pumping cuts could reduce irrigated acreage ~11–17% and gross farm revenue ~10–13.5% across Monterey County, with the saltwater front projected to reach the City of Salinas by ~2060 under current conditions. Read More

Arvin-Edison’s First-of-its-Kind Golden Mussel Treatment Delivers 100% Caged-Mussel Kill + Canal-Wide Control

Arvin Edison Water Storage District reported its copper-based Natrix CA treatment achieved 100% mortality of all caged mussels and effective control across the entire canal system during a 28-day treatment at an initial cost of ~$2.75 million. Consultants from SEPRO recommended a Phase 2 maintenance program of 3–4 treatments per year that could cost about $1.79 million annually (product estimate); no Phase 2 plan has been formally approved yet, and staff will bring concrete recommendations in May. Read More

Trends in the Valley

Regulatory Deadlines Are Stacking Up — and the GEARS Portal Is Struggling

El Rico GSA warned growers that GEARS reports for 7/15/2024–9/30/2025 are due May 1 and that MLJ (Watermark) registration must be completed now or allocations will show as zero. Pixley GSA reported that of ~50 landowner submissions attempted, only 4 went through the State Board’s online GEARS portal, and Tri County Water Authority says the system won’t accept paper submissions. East Turlock GSA Tac invoiced 337 accounts with a 45-day appeal window; Greater Kaweah GSA set a public hearing within ~60 days on WY2024 delinquent Tier 1 and Tier 2 penalties; Lower Tule River Irrigation District warned the State Board to expect data gaps by the May 1 deadline.

Subsidence Frameworks Are Shifting From Groundwater Thresholds to Land-Sinking Rates

West Turlock Subbasin GSA Tac presented a revised approach tying subsidence limits to actual rates of land sinking rather than groundwater-level thresholds, with ~1-mile buffer zones around Merced Irrigation District (MID) and Turlock Irrigation District (TID) canal infrastructure. Greater Kaweah GSA reported west/south subsidence continuing at ~0.4–0.6 ft/yr. Mid-Kaweah GSA said monitoring points are already about one-third of the way to cumulative loss limits, and DWR has begun coordinating subsidence meetings with affected basins.

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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