The 2021 calendar year runoff for the Missouri River basin above Sioux City, Iowa, was 15.2 million acre-feet, 59 percent of average.
The ongoing drought shows no relief in sight, and the U.S. Army Corps of Engineers is predicting runoff into the mainstem reservoir system will remain below normal.
Officials say 2021 was the 10th lowest annual runoff for the Missouri River Basin in 123 years of record-keeping.
Based on current runoff trends, soil moisture, and plains and mountain snowpack, the dry conditions are expected to continue, as mountain snowpack is accumulating at a below-average rate.
The 2022 runoff in the Missouri River basin above Sioux City, Iowa, is forecast to be 21.7 million acre-feet, 84 percent of average. Navigation flow support for the Missouri River is forecasted to be at minimum levels for the first half of the 2022 season, which begins April 1 at the mouth of the river near St. Louis, Missouri.