Earlier-than-normal runoff slowing Missouri River
Officials expect runoff in the Missouri River to be below normal this spring following higher-than-normal February temperatures. The U.S. Army Corps of Engineers predicts runoff -- the amount of moving water in a river -- in spring for the Missou...
Officials expect runoff in the Missouri River to be below normal this spring following higher-than-normal February temperatures.
The U.S. Army Corps of Engineers predicts runoff - the amount of moving water in a river - in spring for the Missouri River in South Dakota to be 85 percent of its normal level, moving 21.6 million acre feet of water.
Runoff was higher than normal last month, measured at 1.9 million acre feet, which was 170 percent of normal for a typical February.
"Above-normal temperatures in upper Missouri River basin melted virtually all of the Plains' snowpack and some low-elevation mountain snowpack," said Jody Farhat, chief of the Missouri River Basin Water Management Division. "Runoff that would normally occur in March and April occurred earlier this year."
Snowpack in areas north of Fort Peck in northeast Montana was 89 percent the average amount by the end of February. Snowpack from Fort Peck to Garrison Dam in North Dakota was even less at 75 percent of average.
"The reduction in forecasted runoff is a result of below-normal mountain snowpack above Fort Peck and Garrison. The remainder of the plains snowpack is light and patchy," Farhat said.
According to USACE, about 80 percent of mountain snowpack accumulates by Mar. 1 and peaks in mid-April.
Electricity production from the six mainstream power plants - Fort Peck, Garrison Dam, Oahe Dam near Pierre, Big Bend Dam near Fort Thompson, Fort Randall Dam near Pickstown and Gavins Point Dam near Yankton - is also expected to be below average, according to USACE. The six dams produced 565 million kilowatt hours of electricity in February, lower than their 621 million kWh average.
The plants are expected to generate 9.1 billion kWh in 2016, a drop from their 10 billion kWh average.
USACE will host five public meetings from April 12 to 14 at sites in Pierre; Bismarck, North Dakota; Nebraska City, Nebraska; Fort Peck, Montana; and Smithville, Missouri. The Pierre meeting is scheduled for 11 a.m. April 14 at the Capitol Lake Visitor Center.
South Dakota releases and water levels
• In February, releases from Fort Randall Dam averaged 13,900 cubic feet per second. Releases will be adjusted this month to correspond to changes at the Gavins Point Dam. The dam stored about 1,351 feet of water, about 91 percent of average.
• Releases from Big Bend Dam in the same month averaged 16,900 cfs and are expected to rise to 18,400 cfs this month to maintain its normal March elevation of 1,420 feet.
• Oahe Dam releases averaged 17,600 cfs in February and are expected to average 17,700 cfs this month. Oahe Reservoir rose by 1.1 feet in February to 1,608 feet, 111 percent of average, and is expected to rise by about 1 foot in March.