The Upper Missouri River Basin has recorded the ninth driest April in 123 years of record keeping, according to the U.S. Army Corps of Engineers.
As a result, Fort Peck Reservoir's elevation is 4 feet lower than it was at this time last year and 9 feet lower than in 2019. Despite the lower water levels, the Corps will drop the lake's level over the next month, declining from an elevation of 2,233 feet to 2,232 feet as water releases are increased from 7,400 cubic feet per second to 9,500 cfs.
Likewise, the Bureau of Reclamation is predicting lower inflows to Bighorn Reservoir this spring — only 66% of average. Inflows spiked temporarily at the first part of April as Buffalo Bill Reservoir released 5,000 cfs to flush sediments down the Shoshone River.
Canyon Ferry Reservoir is currently 2 feet below the minimum level to launch boats at the popular Shannon Recreation Area near the dam, according to Reclamation's website. Inflows to the reservoir are about 2,500 cfs lower than normal for this time of year.
On the Missouri River, runoff was 44% of average, and Corps forecasters are predicting 17.8 million acre-feet will flow into its reservoirs this spring, 69% of average. If realized, the figure would rank as the 22nd lowest calendar year runoff volume.
“I urge all water users, particularly intake owners, to begin preparing for the possibility of lower river levels later this summer and during the fall and winter,” said John Remus, chief of the U.S. Army Corps of Engineers’, Missouri River Basin Water Management Division, in a press release.
Based on the Corps' forecast, flow support for navigation on the lower Missouri River for barge traffic will be reduced during the second half of the navigation season, the agency predicted.
Mountain snowpack above Fort Peck in late March peaked at 86% of normal, while the mountain snowpack in the Fort Peck to Garrison reach peaked in late April at 96% of average. Mountain snowpack normally tops out near April 15. The mountain snowpack graphics can be viewed at: http://go.usa.gov/xARQC.