For Immediate Release: March 6, 2015
Contact: Serena Baker, U.S. Army Corps of Engineers, Northwestern Division
Phone: 503-808-3710 E-mail: serena.baker@usace.army.mil
February runoff higher, but 2015 Missouri River forecast still slightly below normal
Omaha, Neb. — The U.S. Army Corps of Engineers (Corps) Missouri River Basin Water Management Division reports runoff in the Missouri River Basin above Sioux City, Iowa was 2 million acre feet (MAF) during February, 186 percent of normal. The increased runoff was caused by above normal temperatures in the upper Missouri Basin that limited river ice build-up, and melted both plains and low elevation mountain snows. However, the 2015 runoff forecast in the same reach is 24.6 MAF, 97 percent of normal, and the March runoff forecast is about 1 MAF less than in February.
“The reservoirs are designed to capture spring runoff that is stored and released during the summer and fall to provide water for navigation, hydropower, water supply for municipalities and power plants and other uses. Essentially, runoff that would normally arrive in the regions above Fort Peck and Garrison dams during March and April occurred early this year,” said Jody Farhat, chief of the Corps’ Missouri River Basin Water Management Division.
The lower runoff forecasted in March is a result of slightly below normal mountain snowpack above Fort Peck and Garrison dams, drying soil moisture conditions and light plains snowpack. As of March 1, mountain snowpack was 88 percent of normal in the reach above Fort Peck Dam and 97 percent of normal in the reach between Fort Peck and Garrison dams. Typically about 80 percent of the peak mountain snowpack accumulation has occurred by early March. View mountain snowpack graphic at http://www.nwd-mr.usace.army.mil/rcc/reports/snow.pdf.
The total volume of water stored in the Missouri River Mainstem Reservoir System is 57.1 MAF, occupying 1 MAF of the 16.3 MAF flood control zone. “The Corps will continue to monitor snowpack, rainfall-runoff and basin soil conditions to fine tune the regulation of the reservoir system based on the most up-to-date information,” said Farhat.
Beginning in mid-March, releases from Gavins Point Dam will be increased approximately 3,000 cubic feet per second (cfs) per day until navigation target flows are reached. Based on the March 15 system storage check, full-service navigation flow support will be provided for the first half of the Missouri River navigation season. Full-service navigation flow support is generally sufficient to provide a 9-feet-deep by 300-feet-wide channel. Flow support for the second half of the navigation season and the season length will be determined based on the July 1 system storage check. The navigation season opening dates are as follows:
March 23 – Sioux City, Iowa
March 25 – Omaha, Neb.
March 26 – Nebraska City, Neb.
March 28 – Kansas City, Mo.
April 1 – Mouth near St. Louis, Mo.
Read the entire press release at http://www.nwd.usace.army.mil/Media/NewsReleases/tabid/1989/Article/579020/february-runoff-higher-but-2015-missouri-river-forecast-still-slightly-below-no.aspx