Upper Basin Runoff Stays Below Average
The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. February runoff in the Missouri River Basin above Sioux City was 1.0 million acre-feet, 91% of average.
“Runoff into the reservoir system was slightly below average for the month of February and conditions across most of the basin remain dry,” said John Remus, chief of the U.S. Army Corps of Engineers’ Missouri River Basin Water Management Division.
“Mountain snowpack improved in February but is still below average. The plains snowpack, which was below average, has mostly melted. We are forecasting a below- average runoff year for the basin.”
The 2025 calendar year runoff forecast above Sioux City is 22.1 MAF, 86 percent of average. The runoff forecast is based on current soil moisture conditions, plains snowpack, mountain snowpack and long-term precipitation and temperature outlooks.
The volume of water stored in the Missouri River Mainstem Reservoir System is currently 50.4 MAF, 5.7 MAF below the top of the carryover multiple use zone.
Releases from Gavins Point Dam are currently 12,000 cubic-feet-per-second and will remain low through mid-March to continue conserving water in the System, based on the guidance in the Missouri River Mainstem System Master Manual. “While the target winter release from Gavins Point Dam is 12,000 cfs, releases were set at 14,000 cfs for most of February due to extremely cold temperatures and ice conditions on the Missouri River below Gavins Point,” said Remus.
Basin and river conditions continue to be monitored, including plains and mountain snow accumulation, and System regulation will be adjusted based on the most upto-date information.
Fort Peck Dam
Average releases past month – 5,500 cfs Current release rate – 5,500 cfs Forecast average release rate – 5,500 cfs End-of-February reservoir level – 2226.6 feet Forecast end-of-March reservoir level – 2227.5 feet Notes: Releases will remain at 5,500 cfs in March.
The forecast reservoir releases and elevations discussed above are not definitive. Additional precipitation, lack of precipitation or other circumstances could cause adjustments to the reservoir release rates.
