‘Catastrophic’ Failure of St. Mary Siphon Leads to Localized Flooding in Babb
The failure occurred while Bureau of Reclamation personnel were examining a crack in a century-old siphon.
By Amanda Eggert for Montana Free Press
A piece of infrastructure used to divert water from the St. Mary River to the North Fork of the Milk River has suffered a “catastrophic failure,” according to Milk River Project personnel.
The failure involves the St. Mary River Siphon, which is composed of a pair of 90-inch riveted steel barrels that traverse a 3,200-foot section of the St. Mary Valley to divert water to the North Fork of the Milk River.
In a Facebook post, the Milk River Joint Board of Control said the failure occurred at approximately 9:00 a.m. Monday while U.S. Bureau of Reclamation personnel were monitoring a crack in the siphon.
“Thankfully, no one was hurt, but the damage is extensive,” the post reads. “The canal was shut down prior to the failure, but the hillside, Hook’s Hide-Away bar, hotel and roping arena have all been significantly impacted with the water.”
A phone call to Hook’s Hideaway was not immediately returned Monday.
In a press release, the Bureau of Reclamation (BOR) said approximately 600 cubic feet of water per second were running through the canal when the siphon gave way.
The older of the two barrels that comprise the siphon was built in 1915. Issues associated with buckling, seepage and corrosion have challenged project managers for decades, according to the Milk River Joint Board of Control.
“Diversions have been stopped, however flows are expected to continue for as long as 24 to 36 hours while the canal drains,” the bureau wrote in the press release, adding that additional agencies responding to the incident include the Blackfeet Tribe, the Glacier County Sheriff’s Department, the Gallatin County Sheriff’s Department, the National Park Service and Glacier Electric.
In addition to causing “localized property damage,” the flooding may pose public safety risks. A post on the Blackfeet Nation/Blackfeet Tribal Business Council’s Facebook page urges residents to stay out of the area and refrain from all river activities for at least a week.
The BOR wrote that it is considering short-term solutions to address flooding impacts and will conduct detailed assessments of the siphon and reconstruction prospects when it is safe to do so.
Milk River Project Manager Jennifer Patrick did not immediately return a request for comment regarding the failure’s implications for water users dependent on the canal for drinking water and irrigation.
“The Bipartisan Infrastructure Law was designed to mitigate events like this by allocating $8.3 billion for the Bureau of Reclamation to repair aging water delivery systems, secure dams, complete rural water projects and protect aquatic ecosystems,” the agency wrote in the release.
On X, the platform formerly known as Twitter, both Governor Greg Gianforte and U.S. Senator Jon Tester wrote that they are monitoring the situation.
“The state is working with local and federal authorities to identify the extent of the damage caused to the surrounding area and to water users,” Gianforte wrote.
Tester wrote that he has “pressed federal officials for immediate attention to the situation.”
“As the full extent of the damage is evaluated, I’ll continue to be in touch with local leaders and encourage folks to remain away from the affected area,” Tester wrote.
The Bipartisan Infrastructure Law included $100 million earmarked for the Milk River Project. In an August 2021 story, Patrick said much of that allocation would likely be used to rehabilitate the St. Mary’s Diversion Dam, which funnels water from lower St. Mary Lake into the St. Mary Canal. A Bozeman-based construction company recently received an $88 million contract to repair parts of the dam and canal, and was expected to begin construction next month with a forecasted 2027 completion date.
In 2020, a concrete structure on the 29-mile St. Mary Canal collapsed, depriving some irrigators along the Hi-Line of water for multiple months.
Montana Independent News Addendum (Montana senators’ statements):
Senator Steve Daines tweeted at 3:19 p.m.:
I'm monitoring the concerning siphon breach on the St. Mary Canal and have been in contact with local irrigators as well as the Bureau of Reclamation. The damage is serious, and I'm standing by to help local authorities in any way necessary.
At 5:56 p.m. Senator Jon Tester issued the following press release:
(U.S. Senate) — Following a major siphon burst on the Milk River Project near Babb, Montana, U.S. Senator Jon Tester today called on the Biden Administration to provide immediate support for the local community, small businesses, and irrigators. The failure, which caused thousands of gallons of water to flood the surrounding area, has already caused extensive damage to local businesses, and will impact vital irrigation to farmland in the surrounding area.
“The timing of this failure could not be worse because hundreds of farmers and ranchers are currently depending on the Milk River Project to irrigate their crops,” Tester wrote in a letter to Secretary of the Interior Deb Haaland and Secretary of Agriculture Tom Vilsack. “This is a disaster that requires the immediate and full attention of the Department of Interior and the Department of Agriculture. I ask that you swiftly work to ensure that the local community and the irrigators have the resources they need to confront the challenges that lay ahead.”
Tester has been Montana’s leading champion for the Milk River Project and water infrastructure projects across the state. Earlier this month, Tester announced that a more than $88 million contract was awarded to Montana-based NW Construction to complete the St. Mary Diversion Dam Replacement project. The contract is part of the up to $100 million Tester secured for the Milk River Project through his bipartisan Infrastructure Investment and Jobs Act, which he negotiated and helped pass into law. Tester was the only member of Montana’s Congressional delegation to support the legislation.
The first round of funding, $2.5 million, was announced in January and was used for planning and project design in 2022. Tester directly negotiated and wrote the provision of his legislation that provides up to $100 million to rehabilitate the Milk River Project, and in December 2020, he urged Bureau of Reclamation Commissioner Camille Touton to make the St. Mary’s diversion a top priority and get the resources out the door as quickly as possible.
The Milk River Project irrigates over 120,000 acres and provides water to four municipalities, two rural water systems, and two Tribes.
A full list of Montana provisions in Tester’s bipartisan infrastructure law can be found HERE.
At 7:06 p.m. Daines tweeted:
With the second siphon failure at St. Mary’s today I’m keep(ing) close contact with authorities on the ground. Stay vigilant and stay away from the affected areas.