Milk River Project
The Lifeline of the Hi-Line
St. Mary Siphon Failure Updates
On June 17, 2024, the St. Mary Siphon failed, causing significant impacts to the Milk River Project. To stay informed click here.

Wildlife & Recreational Benefits
The Milk River flows over 700 miles creating incredible wildlife habitats, hunting, and recreational benefits.
What is the Milk River Project?
The Milk River Project is beyond remarkable. With over a century of successful operation, this engineering feat diverts water from the St. Mary River on the Blackfeet Reservation, flowing through northern Montana and Glacier National Park, and across southern Alberta, Canada. This project is a testament to the intricate canals, siphons, and diversions designed for a seamless flow of water. The Milk River Project is essential to fulfill Montana’s water demands, catering to eight irrigation districts, Reclamation pump contracts, private contracts, the Blackfeet and Fort Belknap Indian Reservation, and other living communities along the Milk River. The project has created numerous recreational opportunities for the surrounding inhabitants, contributing to the ecosystem’s prosperity and wildlife habitats. With such a prominent and successful project, the Milk River Project has proven to be a symbol of limitless possibilities.
Benefits to Montana’s Economy
How the Milk River Project has been providing to Northern Montana for over 100 years.
18,000
Residents provided drinking water
1,000,000
People fed annually
140,000
Acres of irrigated lands
700+
Farms
729
River miles of wildlife habitat and recreation
You’ve heard the phrase ‘Can’t see the forest through the trees’—but what about the forms through the braces!? This inside view of the St. Mary Siphon inlet structure highlights the incredible work required to support it before the concrete can be poured. Standing at 40 feet tall, this structure is massive—and if you look closely, you might spot some of the Sletten Construction Company crew hard at work!
Inlet: 1,500CY Concrete – 280 Tons of Rebar
#milkriverproject #stmarysiphon #inletstructure ... See MoreSee Less
16 CommentsComment on Facebook
Are the funds for the diversion dam project secure/??
Who's placing the rebar for sletten
Will they pour that thing all at once?
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TrueNorth Steel has been steadily delivering girders to the site, and Sletten Construction Company’s bridge crew is wasting no time assembling and setting them in place. This structure, the St. Mary Siphon Bridge, is a critical component of the overall siphon replacement project. The bridge is designed to support and carry the siphon pipes across the St. Mary River.
#stmarysiphon #milkriverproject ... See MoreSee Less
15 CommentsComment on Facebook
I appreciate the pictures and status reports. Thank you!
Amazing Job Thanks to all for you continued dedication & hard work 👏
I use to broker true north....great company
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It’s been a while since we’ve shared a view of the project from above! This video was taken last week (2.6.25), and while even more progress has been made since then, it gives a great bird’s-eye view of the scale of the work.
NW Construction, Pro-Pipe Corporation and Sletten Construction Company have been working hard this winter to keep everything on track—check it out!
#milkriverproject #stmarysiphon
{Flight is from the inlet to outlet of the St. Mary Siphon} ... See MoreSee Less
11 CommentsComment on Facebook
It is so amazing with the amount of work done! 👍
Unbelievable the work that has been done, like to see the progression done and the whole landscape to conquer
Cool shot. Keep up the good work.
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🔹 Funding Update: St. Mary Siphon Repair Project 🔹
Many of you may have heard that our federal funding is currently delayed. This is true, the funds have been secured, accessing them has proven to be more complex. The Bipartisan Infrastructure Law funding designated for this project remains temporarily frozen due to a federal review process under the "Unleashing American Energy" Executive Order.
Despite this setback, our team is actively working with federal agencies and congressional leaders to expedite the release of these funds. Our Congressional delegation is fully aware of the situation and has been actively engaged in Washington, D.C., advocating on our behalf.
The good news? 🚧💪 Work is still moving forward thanks to funding from the State of Montana and our local stakeholders! Without the State of Montana’s support and a loan package through DNRC from HB6, the project would be on hold—but we’re not stopping this St. Mary Siphon rebuild!!!
#milkriverproject #stmartsiphon ... See MoreSee Less
18 CommentsComment on Facebook
Is it a true siphon or does the water have to be pumped? Or does gravity do all the work? (by tunneling under a hill/mountain as in the Snowy Scheme in Australia) Getting from one river valley into another is complicated.
Fun fact* individuals in charge of this project had known for *17 years* that it was going to need to fail and need to be rebuilt. 17 years. They did nothing to secure finding until it fully failed, then, then they decided it needed to be fixed. 🤦♀️🤷🏽♀️
What about the headworks / diversion? Is it full steam ahead?
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Despite the challenging below zero temperatures, the dedicated crews of NW Construction and Pro-Pipe Corporation continue making steady progress on setting and welding the St. Mary Siphon pipe. NW Construction is staying ahead of the welding team by installing the underdrain sections. This side of the hill has proven to be much rockier than the other, requiring crews to break up the rock to install the drains—unlike the opposite side, where the failure had already cleared much of the material away for us. Despite the extra effort, progress remains steady, and the team is pushing forward.
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8 CommentsComment on Facebook
Amazing what team of great minds and hard work can accomplish
You guys are Awesome Thanks for enduring the very cold weather 👏
Good time of year to have a heated cab…
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Did you ever dream as a kid that building with LEGOs, Lincoln Logs, or Erector Sets could turn into a career? Well, for this crew at Sletten Construction Company, that childhood passion has become reality!
Right now, they’re hard at work constructing and setting the form package for the St. Mary Siphon Inlet structure. Each lift of forms stands about 10 feet tall, making this structure an impressive 40 feet high!
I can’t say enough about the dedication of these guys—working tirelessly in subzero temperatures up in Babb to make this project happen. Hats off to them! 👏❄️
Stay warm and safe all. Happy Friday!
#StMaryProject #SlettenConstruction #milkriverproject ... See MoreSee Less
12 CommentsComment on Facebook
We appreciate all you are doing to bring water back to the Hiline
Great job, keep up the good work!
It's so great to see this project keep moving forward!!!! Congratulations to all!! Can't wait to see water flowing to all our area users!
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