July runoff in the Missouri River Basin above Sioux City, Iowa, totaled two million acre-feet, or 61 percent of average, according to the U.S. Army Corps of Engineers. Runoff was below normal to well below normal in the Fort Peck, Garrison, and Oahe (oh-AH-hee) reaches, while conditions were better farther downstream. John Remus, chief of the Corps’ Missouri River Basin Water Management Division, says warmer, drier weather and limited mountain snowpack have contributed to weak inflows.
The basin’s 2026 runoff forecast remains at 15.4 million acre-feet, or 60 percent of average. If realized, it would rank as the 11th-lowest runoff in the period of record. About 80 percent of the basin remains abnormally dry or in drought, with conditions expected to persist or expand across the Dakotas, Nebraska, and Iowa. Meanwhile, reservoir storage continues to decline. The Corps expects the winter release from Gavin’s Point Dam to remain at a minimum of 12,000 cubic feet per second.
-NAFB