Corps Hikes Gavins Point Releases
Precipitation totaling between 2 to 5 inches fell over central Nebraska and much of South Dakota during the first half of last week. Because of the rain, inflows into the large upstream Missouri River Basin reservoirs have been increasing and causing pool levels to rise, the Corps of Engineers reported May 22. As a result, the Corps increased releases from Gavins Point Dam—the lowest dam on the system—to 60,000 cubic feet per second (cfs.) on May 23.
“Although the mountain snowpack is normal, we still have a little more than 8 inches of snow-water-equivalent coming from the mountain snowmelt and want to ensure we have storage available to capture and manage that runoff,” said John Remus, chief of the Corps’ Missouri River Basin Water Management Division.
The travel time from Gavins Point Dam to the lower Missouri River and the large uncontrolled drainage area diminishes the effects of releases at locations further downstream.
“We are monitoring conditions along the length of the Missouri River and this increase at Gavins Point will not reach Kansas City until after Monday May 27,” Remus said. “By then, the peak flooding from the recent rain should be declining.”
“There is no estimate on how long releases will remain at 60,000 from Gavins Point,” he said. Additional precipitation, lack of precipitation or other circumstances could cause adjustments to the reservoir release rates, the Corps said.
Releases will remain higher than average into the fall because the reservoirs have to be at the base of the annual flood control pool by the beginning of the 2020 runoff season.
“We will continue to monitor conditions and make adjustments as necessary,” said Remus.
Lower Missouri River
The Kansas City Engineer District said May 22 that it continues to monitor the reservoirs and rivers that feed into the Missouri River in Kansas and Missouri.
“Additional projected rainfall could have significant downstream effects on levee systems along the Missouri River,” the district said in a statement. “Our emergency operations center maintains constant contact with levee sponsors and districts to communicate potential risks as they are identified.”
“Protecting lives is our No. 1 priority,” said Col. Doug Guttormsen, Kansas City District commander. “We’ve been holding a lot of water behind our reservoirs and have no immediate plans to increase reservoir releases. However, as localized rainfall continues and the flood storage capacity fills up, our team will individually assess each reservoir in our region, along with the projected weather forecast, to determine if and when water releases will be made.”
