Idaho’s water storage infrastructure has reached historic lows, with reservoirs sitting at just 8 percent capacity as of Wednesday. The National Weather Service (NWS) in Pocatello warns that the outlook for the coming months offers little relief, projecting a warmer-than-normal winter for December, January, and February.
The forecast is driven by a strong El Niño pattern, which carries a greater than 90 percent probability of persisting through the Northern Hemisphere fall and winter of 2026-27. While precipitation chances remain equal for high or low totals across most of the state, projections for northern Idaho and much of Montana lean toward below-normal rainfall and snowfall.
Historic Depletion Rates
The current crisis follows one of the worst water years on record in Idaho. Last month, reservoirs were being drained at a staggering rate of 24,000 acre-feet per day. James Cefalo, Eastern Regional Manager for the Bureau of Reclamation, had projected that stored water would be entirely depleted by the end of August.
As of mid-September, the situation remains critical. The last time reservoir levels approached this severity was in 1993. Rob Van Kirk, analyzing four decades of weather data, noted that the chances of above-average snowfall this winter are slim. He predicts that the 2027 irrigation season will carry serious implications for agricultural operations.
Farmers Adjust to Scarcity
Agricultural producers in southeastern Idaho are already making significant operational changes to conserve resources. Adam Young, a board member of the Bingham Groundwater District, farms approximately 2,600 acres near Blackfoot. This year, Young removed 100 acres from production and set aside an additional 22 acres for the U.S. Department of Agriculture’s Conservation Reserve Enhancement Program.
Young implemented further cutbacks this fall, bringing his total reduction to about 300 acres. These adjustments reflect a broader trend among irrigators who face uncertain allocations. Van Kirk suggested that farmers might receive only one-third of their usual water allocation in 2027, a stark contrast to 2026, when many producers fared better than expected.
Legal Framework and Future Projects
Idaho law prioritizes senior surface water rights during shortages. Groundwater users are required to have plans in place to recharge the Eastern Snake Plain Aquifer when supplies dwindle. The 2024 Stipulated Mitigation Agreement, a four-year plan, was designed to protect wells from curtailment, addressing threats that junior groundwater users faced prior to that year.
State lawmakers are also looking toward long-term infrastructure solutions. Sen. Kevin Cook is advocating for major water storage projects, including the rebuilding of the Teton Dam. Meanwhile, local advocates like Young are pushing for automated check structures to improve water efficiency on existing systems.
The Idaho Department of Water Resources issued a statewide drought declaration in April, highlighting the severity of the ongoing dry spell. With El Niño events typically lasting nine to 12 months and occurring every two to seven years, state officials and farmers alike are bracing for a prolonged period of water scarcity.