Missouri River Basin Water Management

The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. April runoff in the Missouri River Basin above Sioux City was 1.4 million acre-feet, 48% of average. “Runoff into the reservoir system was below average for the month of April, and runoff was below average in all reaches,” said John Remus, chief of the U.S. Army Corps of Engineers' Missouri River Basin Water Management Division. “Drought or abnormally dry conditions are currently present in 75% of the basin, and conditions have worsened in the Fort Peck reach and parts of the Garrison reach in the last month. As a result, the runoff forecast was lowered by 1.9 MAF from last month.”

The 2025 calendar year runoff forecast above Sioux City is 22.1 MAF, 86% of average. The runoff forecast is based on current soil moisture conditions, plains snowpack, mountain snowpack, and long-term precipitation and temperature outlooks. Average is 25.7 MAF. The March 3 mountain snowpack in the Fort Peck reach was 89% of average, while the mountain snowpack in the Fort Peck to Garrison reach was 91% of average. By March 1, about 79% of the total mountain snowfall has typically accumulated. Mountain snow normally peaks near April 17.

The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. January runoff in the Missouri River Basin above Sioux City was 0.7 million acre-feet, 92% of average. Runoff was near or below average for most of the Missouri River Basin, and most of the upper basin had below-normal precipitation.

For the 2024 calendar year, Missouri River basin runoff above Sioux City, Iowa totaled 23.3 million acre-feet, 91% of average. Dry conditions continue to affect the upper Missouri River Basin at the start of the 2025 calendar year, so the U.S. Army Corps of Engineers is forecasting below-average runoff into the mainstem reservoir system. For 2025, runoff in the Missouri River basin above Sioux City, Iowa is forecast to be 20.2 MAF, 79% of average.

Drought is present across 73% of the Basin. August runoff was 1.2 MAF, 86% of average above Sioux City. The updated upper Basin runoff forecast for is 23.8 MAF, 92% of average. On Sept. 1, the volume of water stored in the System was 55.1 MAF, or 1.0 MAF below the base of the flood control zone. Storage is expected to decline through the fall. Expect System storage to be about 4.7 MAF below the base of flood control zone at the start of the 2025 runoff season

July runoff in the Missouri River basin above Sioux City, Iowa was 2.8 million acre-feet, 85% of average with below-average runoff in the upper three reaches and above-average runoff in the lower three reaches. The annual runoff forecast above Sioux City, Iowa is 23.9 MAF, 93% of average. “July brought warmer and drier weather to the Missouri River Basin,” said John Remus, chief of the U.S. Army Corps of Engineers' Missouri River Basin Water Management Division.

This is the final call of the 2024 flow test. The average daily release rate from Fort Peck is 8,000 cfs and monitoring of pallid sturgeon continues. However, there is no indication of spawning therefore a drift flow was not undertaken. An update on the Wolf Point and Culbertsn gauges was provided. Monitoring of the from the test such as pool levels, erosion, dam safety, etc., will continue once the test is complete later this fall.

The average daily release rate from Fort Peck is 8,000 cfs and monitoring of pallid sturgeon continues. Irrigators asked about the Wolf Point gauge and USACE will be talking to the USGS to get more information on the gauge. Monitoring of the from the test such as pool levels, erosion, dam safety, etc., will continue once the test is complete later this fall.

The average daily release rate from Fort Peck is 8,000 cfs and monitoring of pallid sturgeon continues. Monitoring of the from the test such as pool levels, erosion, dam safety, etc., will continue once the test is complete later this fall.

Significant rainfall led to an above average runoff in the upper Missouri River Basin. June runoff was 6.6 million acre-feet, which is 119% of average and 2.6 MAF higher than forecast.The rainfall totals exceeded 600% of normal over the 24-hour period. In response, releases from Fort Randall and Gavins Point dams were reduced, but they could not completely offset all the flooding.

The second test flows from Fort Peck Dam to comply with the 2018 Biological Opinion resumed with a lower peak set at Wolf Point, Montana of 20,000 cfs. The average daily release rate from Fort Peck is 8,000 cfs and monitoring of the flow's effects continue.

The FINAL ad-hoc call. The Missouri River continues to drop below flood stage. The Kansas City and Omaha Districts are preparing for post-flood assessments and repairs. Gavins Point Dam releases have increased to 15,000 cfs as a return to normal operations.

The Missouri River crest is declining faster than expected. The Kansas City District remains ready to address requests for assistance. The Omaha District has one levee surveillance team on standby and is transitioning to post-flood recovery. Gavins Point Dam releases remain at 13,000 cfs.

The Kansas City District prepares for a slightly higher Missouri River crest to reach areas downstream of Kansas City following heavy rains and flash flooding overnight July 3. The Omaha District continues levee surveillance with fewer teams as they transition to post-flood recovery. Gavins Point Dam releases remain at 13,000 cfs.

The Kansas City District prepares for a slightly higher Missouri River crest to reach areas downstream of Kansas City following heavy rains and flash flooding overnight July 3. The Omaha District continues levee surveillance with fewer teams as they transition to post-flood recovery. Gavins Point Dam releases remain at 13,000 cfs.

The Kansas City District prepares for the Missouri River crest to reach the area. and the Omaha District continues levee surveillance as they transition to post-flood recovery. Gavins Point Dam releases remain at 13,000 cfs.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were recommenced Monday, June 17 after a delay. The test flow's second peak resumed but with a lower peak set at Wolf Point, Montana of 20,000 cfs. Flows continue stepping down, the spillway gates have closed, and a peak release of 8,000 cfs is scheduled for July 6.

The Kansas City District prepares for the Missouri River crest to reach the area. and the Omaha District continues levee surveillance as they transition to post-flood recovery. Gavins Point Dam releases remain at 13,000 cfs.

The Kansas City District prepares for the Missouri River crest to reach the area. and the Omaha District continues supporting local communities and levee sponsors. Gavins Point Dam releases remain at 13,000 cfs.

As the flood's crest moves down the Missouri River, following heavy rains, the Omaha and Kansas City Districts continue providing support to local communities and levee sponsors. Gavins Point Dam releases remain at 13,000 cfs. Spokespersons from state and local Emergency Response functions join the discussion.

As the flood's crest moves down the Missouri River, following heavy rains, the Omaha and Kansas City Districts are providing support to local communities and levee sponsors. Gavins Point Dam releases remain at 13,000 cfs. Spokespersons from state and local Emergency Response functions join the discussion.

As the flood's crest moves down the Missouri River, following heavy rains, the Omaha and Kansas City Districts are providing support to local communities and levee sponsors. Fort Randall Dam will begin power generation and Gavins Point Dam is lowering releases to 13,000 cfs.

As the flood's crest moves down the Missouri River, following heavy rains, the Omaha and Kansas City Districts are providing support to local communities and levee sponsors. Fort Randall Dam will begin power generation and Gavins Point Dam is lowering releases to 16,000 cfs.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were recommenced Monday, June 17 after a delay. The test flow's second peak resumed but with a lower peak set at Wolf Point, Montana of 20,000 cfs. Flows begin stepping down today and the gates are expected to close next week.

Extremely high unregulated tributary flows following heavy rains have led to destructive flooding along the tributaries and will send floodwaters into the Missouri River. Fort Randall Dam is operating with minimal releases and Gavins Point dam closed the spillway gates today and lowered releases to 20,000 cfs. The Omaha and Kansas City Districts are providing support to local communities

Extremely high unregulated tributary flows following heavy rains have led to destructive flooding along the tributaries and will send floodwaters into the Missouri River. Fort Randall Dam is operating with minimal releases and Gavins Point dam continues releases at 24,000 cfs with 15,000 cfs through the spillway and 9,000 cfs through the powerhouse. Even with the lower than normal release, high flows more than 90,000 cfs on the unregulated Big Sioux River are contributing to high stage forecasts on the Missouri River.

Extremely high unregulated tributary flows following heavy rains have led to destructive flooding along the tributaries and will send floodwaters into the Missouri River. Fort Randall Dam is operating with minimal releases and Gavins Point dam has releases lowered to 24,000 cfs with 15,000 cfs through the spillway and 9,000 cfs through the powerhouse. Even with the lower than normal release, high flows more than 90,000 cfs on the unregulated Big Sioux River are contributing to high stage forecasts on the Missouri River.

Heavy rains rainfall and forecast inflows into the Gavins Point reservoir from the Niobrara River, and other tributaries, have spurred release changes at Fort Randall and Gavins Point dams. Additionally, the Omaha District and Kansas City District Emergency Operations Centers have activated to provide response to local communities.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were recommenced Monday, June 17 after a delay due to the Missouri River gage at Williston's forecast stage of 22.6 feet on June 15. Once river stages dropped below 22 feet, the test flow's second peak resumed but with a lower peak set at Wolf Point, Montana of 20,000 cfs. 2,500 cfs lower than the initially planned peak.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were scheduled to start increasing this week to 22,000 cfs. However, flow increases are delayed due to the Missouri River gage at Williston's forecast stage of 22.6 feet on June 15. A test protocol halts or delays release increases if the Williston gage is forecast to go about 22 feet.

May runoff for the Basin above Sioux City, Iowa was 3.5 MAF,104% of average. The annual runoff forecast above Sioux City, Iowa is 21.0 MAF, 82% of average, and 1.8 MAF higher than last month's forecast. System storage is currently 55.0 MAF, 1.1 MAF below the top of the carryover multiple use zone. During May, System storage increased 1.0 MAF.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were lowered to a target of 10,000 cfs (at Wolf Point) and start increasing around mid-June to reach 22,000 cfs. The test is required under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings are aimed at updating the public on test progress, monitoring and planned operations.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were lowered to a target of 10,000 cfs (at Wolf Point) and start increasing around June 11 reachng 22,000 cfs on June 20. The test is required under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings are aimed at updating the public on test progress, monitoring and planned operations.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were lowered to a target of 10,000 cfs (at Wolf Point) and will held through mid-June. The test is required under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings are aimed at updating the public on test progress, monitoring and planned operations.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion were lowered to a target of 10,000 cfs (at Wolf Point) and will held through mid-June. The test is required under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings are aimed at updating the public on test progress, monitoring and planned operations.

Spring precipitation in the Missouri River Basin brought some much-needed moisture. April runoff was 2.1 MAF, 71% of average, for the basin above Sioux City, Iowa. The annual runoff forecast for the upper Missouri River Basin above Sioux City is 19.2 MAF, 75% of average, and 1.7 MAF higher than last month's forecast. Drought conditions in the upper Basin are likely to persist. System storage is 49.9 MAF, 6.2 MAF below the top of the carryover multiple use zone.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion are beginning to be lowered to a target of 10,000 cfs on May 9 and held through mid-June. The test is required under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings are aimed at updating the public on test progress, monitoring and planned operations.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion began Fri., April 26. The 2018 Biological Opinion requires the test under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. These weekly virtual meetings during the flow test to update the public on test progress, monitoring and planned operations.

Test flows from Fort Peck Dam to comply with the 2018 Biological Opinion will begin Fri., April 26. The 2018 Biological Opinion requires the test under the Endangered Species Act for operation of the Missouri River Mainstem Reservoir System. The U.S. Army Corps of Engineers will host weekly virtual meetings during the flow test to update the public on test progress and planned operations.

The latest 2024 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa shows slight improvement. The 2024 calendar year runoff forecast above Sioux City is 17.5 million acre-feet (MAF), 68% of average. March runoff in the Missouri River Basin above Sioux City was 1.8 MAF, 59% of average. Even with the lower than average runoff forecast the hydrologic conditions are sufficient to conduct a flow test from Fort Peck Dam” said Remus. “The flow test is a requirement of the 2018 Biological Opinion and is meant to determine if there is a Fort Peck Dam water management scenario that could benefit the Pallid Sturgeon.

A warm February led to increased snowmelt and runoff in the Missouri River Basin above Sioux City, Iowa. February runoff was 1.8 million acre-feet, 161% of average with above average runoff in every reach except Sioux City, which was near average. However, the updated 2024 calendar year runoff forecast for the basin continues to be below average.

January runoff in the Missouri River Basin above Sioux City was 0.4 million acre-feet, 56% of average. Runoff was well-below-average due to much-below-normal temperatures over the whole Missouri River Basin and below-normal precipitation over most of the upper basin. The 2024 calendar year runoff forecast above Sioux City is 18.8 MAF, 73% of average. The runoff forecast is based on current soil moisture conditions, plains snowpack, mountain snowpack, and long-term precipitation and temperature outlooks.

As the colder, winter temperatures enter the basin, USACE will closely monitor Missouri River ice conditions between the System reservoirs and downstream of Gavins Point Dam for potential ice jams that could impact river stages and water intakes. Runoff in the upper Missouri River Basin above Sioux City, Iowa, was 1.1 million acre-feet (MAF) during November, 107% of average. The 2023 calendar year runoff forecast is 29.9 MAF, 116% of average. Average annual runoff is 25.7 MAF.

Rainfall in the Missouri River Basin above Sioux City, Iowa, was above normal for August, resulting in above average runoff. However, due previous years' drier-than-normal conditions leaves the total storage in the Missouri River mainstem reservoir system below normal. Based on the Sept. 1 system storage, Gavins Point Dam winter releases will be 13,000 cfs, per the Master Manual criteria. This call focuses on winter release rates and storage at Fort Peck meeting the criteria for a planned Test Flow.

Above average rainfall and fast-melting snow led to above average runoff in the upper Missouri River Basin in June. Runoff above Sioux City, Iowa was 6.7 million acre-feet, which is 122% of average. The annual runoff forecast above Sioux City, Iowa is 29.2 MAF, 114% of average, and about 2.4 MAF higher than last month's forecast. Precipitation was normal to much-above-normal for the month of June in much of Montana, southern and east-central North Dakota, and western South Dakota. Below-normal precipitation occurred in eastern South Dakota and into the lower Basin.

Warm temperatures in the mountainous region of the upper Missouri River Basin has led to a quick melt of the mountain snowpack. The rapid melting combined with precipitation in the western half of the Basin resulted in above-average inflow into the reservoir system. May runoff for the Basin above Sioux City, Iowa was 4.9 million acre-feet, 144% of average. "The warm temperatures in the northern Rockies has melted the snow earlier than is typical,” said John Remus, chief of the U.S. Army Corps of Engineers' Missouri River Basin Water Management Division. “With much of the mountain snowpack already melted, the Basin will need additional rainfall to continue the trend of above-average runoff.”

Late season plains snowpack accumulation and subsequent melting led to increased runoff throughout the upper Missouri River Basin during April. For the month, runoff was 4.7 million acre-feet, 159% of average, for the basin above Sioux City, IA. The annual runoff forecast for the upper Missouri River Basin above Sioux City, IA is 26.9 MAF, 105% of average, and 0.5 MAF higher than last month's forecast. However, soil moisture remains slightly below normal in eastern Montana and the western Dakotas, and well below normal in Nebraska. Even with the plains snowmelt, soils dried out in late April over a large portion of the upper basin.

The updated 2023 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. The 2023 calendar year runoff forecast above Sioux City is 21.5 million acre feet, 84% of average. The runoff forecast is based on current soil moisture conditions, plains snowpack, mountain snowpack, and long-term precipitation and temperature outlooks. February runoff in the Missouri River Basin above Sioux City was 1.0 MAF, 86% of average.

The updated 2023 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. The 2023 calendar year runoff forecast above Sioux City is 21.1 MAF, 82% of average. The runoff forecast is based on current soil moisture conditions, plains snowpack, mountain snowpack, and long-term precipitation and temperature outlooks.

For the 2022 calendar year, Missouri River basin runoff above Sioux City, Iowa totaled 19.3 million acre-feet, 75% of average. This was the 30th lowest annual runoff for the Missouri River Basin in 125 years of record-keeping. The ongoing drought shows little relief in sight and the U.S. Army Corps of Engineers predicts runoff into the mainstem reservoir system will remain below normal. For 2023, runoff in the Missouri River basin above Sioux City, Iowa is forecast to be 20.8 MAF, 81% of average.

The September update shows drought conditions in the Missouri River Basin above Sioux City, Iowa, continued throughout August. Per the Master Manual and the September 1 System storage check, winter releases from Gavins Point Dam will be 12,000 cubic feet per second (cfs), as part of the overall water conservation measures. August runoff was 0.9 MAF, 62% of average above Sioux City, and 0.6 MAF or 49% of average above Gavins Point Dam. The portion of the basin that drains into Oahe Reservoir was particularly dry, only experiencing 10% of its average August runoff. The 2022 calendar year forecast for the upper Basin, updated on September 1, is 20.2 million acre-feet (MAF), 78% of average. Average annual runoff for the upper Basin is 25.8 MAF.