NorthWestern Energy Announces Missouri River Drawdown for Black Eagle Dam Spillway Project

Great Falls, Mont. - July 15, 2026 - NorthWestern Energy will temporarily draw down the Missouri River upstream of Black Eagle Dam from July 31 through mid-September to allow construction crews to complete critical upgrades as part of the Black Eagle Dam Spillway Project.

Work will take place on the upstream west-facing side of the dam and include installing new support structures and components of the spillway. These improvements are designed to enhance the overall integrity of the dam.

In addition to strengthening the structure, the upgrade will eliminate the need for NorthWestern Energy hydro crews to manually remove ice buildup during extreme winter conditions, improving both operational efficiency and worker safety.

River Access Impacts

For public safety during the project:

• The Missouri River will be closed to public use and access from downstream of Broadwater Bay to Black Eagle Dam, including the kayak launch and dock at West Bank Park.
• Broadwater Bay boat launch will remain open, as will the non-motorized take-out ramp at Oddfellows Park and the river upstream of Broadwater Bay.

Public Safety Reminder

The public is warned to stay out of the riverbed during the drawdown. Exposed areas contain:

• Deep mud
• Unstable ground
• Rapidly changing water conditions
• Unexpected hazards.

These hazards pose serious risks to both people and pets.

"We appreciate the public's cooperation as we complete this important infrastructure project," said NorthWestern Energy Manager Power Generation Jeremy Butcher. "These upgrades will help ensure the continued safety, reliability, and efficiency of hydroelectric operations at Black Eagle Dam."

Work on the Black Eagle Dam Spillway Project will continue during the river draw down and temporary closures of the River's Edge Trail near the dam north and south of the Missouri River will be required for the safety of the public and crews.

For more information and updates, visit https://www.northwesternenergy.com/about-us/our-projects/black-eagle-dam-spillway-project

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NorthWestern Energy - Delivering a Bright Future

NorthWestern Energy, provides essential energy infrastructure and valuable services that enrich lives and empower communities while serving as long-term partners to our customers and communities. We work to deliver safe, reliable, and innovative energy solutions that create value for customers, communities, employees, and investors. We do this by providing low-cost and reliable service performed by highly-adaptable and skilled employees. We provide electricity and / or natural gas to approximately 850,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. We have provided service in South Dakota and Nebraska since 1923 and in Montana since 2002.

Media Contacts:

Jo Dee Black

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