TID sustains out-of-district replenishment water program to boost subbasin groundwater recharge

TID sustains out-of-district replenishment water program to boost subbasin groundwater rechargeDespite reservoir projections dipping below historical trigger levels, the Turlock Irrigation District will continue supplying surface water to external landowners to incentivize in-lieu groundwater recharge across the shared subbasin.

The board reached a consensus to maintain out-of-district deliveries through October 2026, projecting a total seasonal delivery of roughly 11,281 acre-feet.

Continuing the program will impact internal TID growers by reducing their available on-farm water allocation by approximately 0.6 inches for the remainder of the season.

The district's water supply was bolstered by a flood control deviation with the Army Corps of Engineers that saved over 150,000 acre-feet in Don Pedro reservoir.

Public commenters noted the program's success, citing a reduction in overall groundwater pumping by nearly 30,000 acre-feet and the fallowing of over 10,000 acres outside the district.

The Turlock Irrigation District (TID) Board of Directors reached a consensus on June 9 to maintain its out-of-district replenishment water program through the end of the 2026 irrigation season, prioritizing regional groundwater sustainability despite a projected dip in reservoir levels. Under the program, TID supplies surface water to agricultural lands outside its service area but within the shared Turlock Subbasin. By providing surface water, the district incentivizes landowners to leave their groundwater pumps off—a practice Director Joe Alamo described as "in-lieu recharge" that is highly efficient for the drought-prone basin. AGM of Water Resources Tou Her reported that Don Pedro Reservoir is projected to drop to an elevation of approximately 780 feet by October 7, the start of the flood control period. This falls below the historical 795-foot average that typically triggers a board review of external water sales. If deliveries continue through October, TID projects it will send an additional 6,890 acre-feet of water out of the district, bringing the 2026 seasonal total to roughly 11,281 acre-feet. Her noted this would reduce the available on-farm water allocation for internal TID growers by approximately 0.6 inches for the remainder of the season, or 1 inch total for the year. Despite the minor impact on internal ratepayers, the board opted to take no action to halt the program, allowing it to proceed. Director Michael Frantz argued that the district's ongoing canal automation and water conservation projects—funded in part by the out-of-district water sales—offset the risks of continuing deliveries during "in-betweener" hydrological years. TID’s water position was significantly bolstered earlier in the year through a strategic deviation from standard flood control curves. Water & Power Resource Planning Department Manager Olivia Cramer noted that by coordinating with the Army Corps of Engineers to hold water in designated flood control space, the district conserved over 150,000 acre-feet. Without this maneuver, reservoir elevations would currently sit at 810 feet rather than 822.5 feet. TID is currently seeking a formal five-year pilot deviation to adjust autumn drawdown requirements. The replenishment program is already showing tangible impacts on the subbasin. During the meeting's public comment period, an eastside representative reported that the availability of surface water, combined with a tiered groundwater fee structure and an incentivized fallowing program, helped reduce overall groundwater pumping by nearly 30,000 acre-feet last year. Moving forward, the board directed staff to develop a new, formalized metric to replace the 795-foot elevation trigger by the fourth quarter to guide future out-of-district allocations.