Corps updates stakeholders on Missouri River Mainstem System operations

Missouri River Water Management Division
Published Oct. 23, 2020
Public Meetings are held each spring and fall across the Missouri River basin.

Public Meetings are held each spring and fall across the Missouri River basin. Fall public meetings provide an update on current year's runoff and reservoir operations as well as planned operations for the next year's runoff season. The Annual Operating Plan for the next year's runoff season is released for public comment in September, presented at the public meetings and finalized at the end of the calendar year. Spring public meetings provide a status of mountain snowpack, a runoff forecast for the year, and how operations during the runoff year will meet the authorized purposes for the Missouri River Mainstem System.

The US Army Corps of Engineers Missouri River Water Management Division hosted an update call on Thursday, Oct. 22, for Congressional representatives, Tribal, and state and local government officials, to include emergency managers, local levee sponsors and the media to discuss current conditions, and the projected operation of the mainstem reservoir system as part of the Draft Annual Operating Plan which was released in mid-September for public comment.

The Corps also announced two virtual public meetings scheduled for Monday, Nov. 2. The meetings will take place at 1:30 p.m. and 6 p.m. More details are available below and on the Missouri River Water Management Division website at:

The following are excerpts from the call. The full recording is available for download at: 

John Remus, Chief Missouri River Water Management Division

“I want to assure everyone in the basin that the Corps remains fully committed to our Flood Risk Reduction mission, protecting stakeholders when we can from significant hydrologic events that pose a threat to human health and safety.  We are also committed to supporting the authorized purposes as outlined in the master manual.”

“2020 has been an unusual year.  We began the year with wetter than average conditions in the basin and early forecasts indicated another high runoff year.  However, as many of know, the basin dried up, and dried up quickly.  We have transitioned from evacuating excess flood water to managing the system to meet flow targets.

We are currently meeting all full-service navigation flow targets and will continue do so through the end of the navigation support season, which ends on December first (Dec. 1) at the mouth.”

Kevin Grode, Reservoir Regulation Team Lead

“The upper basin runoff for 2020 is forecast to be 30.2 million acre-feet, which is about 4 million acre-feet more than the long-term average.  The above average runoff this year was due to the much wetter-than-normal soil conditions throughout the basin during the spring.  Conditions throughout the basin have changed considerably over the last 6 months.  Now, most of the basin is experiencing some form of drought.”

“Upper basin runoff comes from three components:  plains snowmelt, mountain snowmelt and rainfall.  The snow has just started accumulating in the mountains and upper plains.  In early January we will develop our upper basin runoff forecast for 2021.  We will update the runoff forecast on a monthly basis, and more often if changing basin conditions dictate.”

“The Gavins Point winter release rate is determined based on the September 1 System storage. Per the September 1 System storage, winter releases from Gavins Point will be at least 17,000 cubic feet per second.  Releases will be reduced to winter levels beginning around November 22nd.”

Mike Swenson, Power Production Team Lead

“System storage peaked in mid-July at 61.8 million acre feet, utilizing 35 percent of the total flood storage.  System storage is currently 57.9 million acre feet, 1.8 million acre feet above the base of the flood control pool.  Based on the latest monthly study, system storage is expected to start next year’s runoff season 800,000 acre feet below the base of the flood control pool.  Fort Peck, Garrison, and Oahe are currently 3.4, 1.6, and 1.5 feet above the base of their respective flood control pools.  These three reservoirs are expected to start next year’s runoff season about one foot below the base of their respective flood control pools.” 

“Fort Peck releases are currently 6,000 cubic feet per second and are expected to range from 9,500 cubic feet per second to 10,000 cubic feet per second this winter.  Garrison releases are currently 13,000 cubic feet per second.  December releases will be set at 16,000 cubic feet per second in anticipation of possible ice formation and river freeze-in.  Releases will be adjusted based on river conditions, with winter releases expected to reach 19,000 cubic feet per second in January and February. Fort Randall winter releases will average about 15,000 cubic feet per second to maintain the Gavins Point pool and support the winter release from Gavins Point.”

Eileen Williamson, Deputy Director of Public Affairs, Northwestern Division

“On November 2nd we will host two virtual public meetings at 1:30 p.m. and 6 p.m. We have posted links to the meetings at”

“Participants are encouraged to submit questions before the webinars using the ‘Submit your questions in advance’ link in the meeting announcement.”

Additional details on forecast development and using the Missouri River Water Management website are available for download from the meeting announcements as well.

Eileen Williamson

Release no. 20-147