OMAHA, NE – August runoff in the Missouri River Basin above Sioux City, Iowa was 1.0 million acre-feet (MAF), 73% of average. Runoff was well below normal in the Fort Peck and Garrison reaches due to dry soil moisture conditions and areas of below-normal precipitation. Runoff was above normal for the Oahe, Fort Randall, and Gavins Point reaches, and near normal in the Sioux City reach, mostly due to above-normal precipitation during parts of August.
“August runoff was higher than forecast in the lower reaches of the upper Missouri River Basin above Sioux City due to late summer rainfall. In addition, rainfall below Gavins Point allowed the System reservoirs to maintain lower release rates while meeting the reduced navigation flow...
The U.S. Drought Monitor indicates that over 83% of the Missouri River Basin is abnormally dry or in drought conditions. Drought conditions are expected to improve in Colorado, southern Wyoming, and western Nebraska and Kansas by the end of November as El Nino conditions strengthen. September runoff in the upper Basin is forecast to be well-below average, especially in the Fort Peck and Garrison reaches. The updated 2026 calendar year forecast for the upper Basin is 15.4 MAF, 60% of average. Average annual runoff for the upper Basin is 25.7 MAF.
Brendin Ailles, a U.S. Army Corps of Engineers' (USACE) Seattle District employee on a detail with the district's emergency management branch, shares how he was first introduced to USACE as a child and shares an update on the levee rehabilitation work he's doing now, in Skagit County, Wash., Aug. 12, 2026.
Public Law 84-99 authorizes USACE to repair or restore eligible flood risk reduction works damaged by recent flooding.
