A spokesman for the U.S. Army Corps of Engineers say runoff into the upper Missouri River basin for 2019 is nearly double its average.
The latest data from the Corps says 38.3 million acre feet of runoff has been recorded in the basin above Sioux City as of July 1st, contributing to continued flooding downstream. The chief of the Corps Missouri River Basin Water Management Division, John Remus,says current projections call for the second-highest yearly runoff total in the history of Missouri River recordkeeping.
“The July 1st forecast for runoff in the basin above Sioux City is 49.9 million acre feet,” Remus says. “This is slightly lower than our June 1st forecast of 50 million acre feet. If realized, this runoff will be the second-largest runoff in the 120 years of records.” The forecast amount would be second only to 2011, when 61 million acre feet of runoff was recorded.
Remus says the reservoirs in the upper basin designed for flood control storage are nearly full. “Reservoir system storage is currently 68.4 million acre feet,” according to Remus. “This is just above the base of the system’s exclusive flood control zone and 12.3 million acre feet and of the 16.3 million acre feet of total flood control storage is currently occupied.”
Remus says the Corps is anticipating getting some additional flood control storage back in Montana and Wyoming in the near future, which will bring additional water to dams in North Dakota and South Dakota. “The Bureau of Reclamation has been storing runoff in the flood control zones on some of their projects in the upper basin,” Remus says. “They are beginning to release water now. We should be seeing that water from the bureau projects at Fort Peck and Garrison in the next week or so.”
Releases from Gavins Point Dam in Yankton, South Dakota, the lowest dam on the system, remain at nearly twice their normal levels due to the increased runoff.
(By Ryan Matheny, KMA, Shenandoah/ Photo courtesy of Fremont County Emergency Management)