Tribal, Federal Officials Say ‘Catastrophic’ Breach of St. Mary Canal Siphon will have Dire Consequences Across Montana

Responsible for irrigating 120,000 acres and providing drinking water to 14,000 municipal users along the Hi-Line, the 115-year-old diversion system near Babb conveys water from the St. Mary to the Milk River

By Tristan Scott
St. Mary Siphon Failure Near Babb on Jun 17, 2024. Courtesy image

Calling the failure of a 115-year-old water-conveyance system near Babb “catastrophic,” federal, tribal and local officials responded Monday to a breach of the St. Mary Canal siphon east of Glacier National Park that caused flooding, erosion and washouts but no reported injuries.

Officials monitoring the situation say the antiquated system was slated for an overdue $100 million infrastructure replacement project set to begin next month, and that the failure of the canal siphon will have devastating long-term consequences to irrigators and municipal water users across Montana’s northern tier.

Ryan Newman, the Bureau of Reclamation’s area manager for Montana, said officials had been monitoring a crack in one of two diversion siphons that conveys water from the St. Mary River to the Milk River, irrigating 120,000 acres of ranchland along Montana’s Hi-Line while providing drinking water to 14,000 municipal users. The initial breach occurred at approximately 8:45 a.m. Monday, releasing 600 cubic feet of water per second and leading to local flooding and bank erosion, with some areas resulting in washouts estimated to run 30- to 50-feet deep.

The unmitigated rush of water from the breached siphon, which has a 90-inch diameter and is 3,600 feet long, caused a second breach to occur in an adjacent siphon, causing additional private property damage while also threatening public safety, prompting emergency road closures and and disrupting utilities. Although responders with the federal Bureau of Reclamation shut off the siphons at the diversion headworks, they expect that the affected section of canal, which is nine miles long and filled with water, will take between 24 and 36 hours to drain completely.

“Emergency response teams have been deployed to contain and evaluate the damage,” Newman said. “Water flows were naturally diverted back to the St. Mary River and helped mitigate the potential for additional flooding in the surrounding area.”

Emergency response teams and local law enforcement are involved in the response efforts. Newman said he was especially grateful for the efforts of law enforcement from the  Blackfeet Nation, the National Park Service and the Glacier County Sheriff’s Department, as well as utilities workers from Glacier Electric who were still working late Monday “to limit the impacts of the breach and ensure people remain safe.”

According to Newman, the Bureau of Reclamation is “coordinating assets and experts” to assess the damage and potential cause of the failure and will “evaluate both short-term solutions, if any, along with long-term rebuild options.” Detailed inspections will begin as soon as the water empties from the line and surrounding canal, he said. 

The breach occurred on reservation land managed by the Blackfeet Nation, where tribal officials remained hopeful that repairs were feasible; however, they conceded that the prospect of short-term repairs were unlikely given the age of the infrastructure and the scale of the failure.

“We’re not going to know the extent of this catastrophic failure until Wednesday afternoon when the canal drains and we can assess the damage,” Blackfeet Water Director K. Webb Galbreath told the Beacon Monday afternoon. “This is just my opinion, but it’s done. There is no fixing it. It’s going to require a whole refurbishment. And in the meantime, it’s going to be a catastrophe for everybody downstream, not only economically to the ranchers and farmers, but also to the municipalities; drinking water, irrigation, it’s going to have a domino effect in my mind.”

Jennifer Patrick, project manager the Milk River Joint Board of Control, said the system has been prioritized for upgrades and replacement for decades; however, due to a complex jurisdictional matrix spanning state, federal and tribal jurisdictions and crossing the U.S.-Canada border, coupled with an outmoded cost-share agreement that puts 73.96% of the financial onus on irrigators and water-users, the capital to replace the St. Mary Diversion Dam and Canal has remained elusive.

“This project was authorized in 1905, and the cost-share allocations are based on 1905 language,” Patrick said in an interview. “So, we have to come up with the majority of funding to replace the system, and that comes out to over $50 million. So, the cost-share benefit doesn’t quite pencil out for us.

“This system is 50-plus years over its shelf life,” Patrick continued. “Fifty years ago, if we had each put ten cents away, we might have had enough money to do this. But we don’t have the money. This failure could have happened 50 years ago, or it could have happened 20 years ago, or it could have happened today. And it just so happens that it happened today.”

The flooding damaged private property located near the breach, impacting local infrastructure and posing risks to public safety, Galbreath said. Roads are closed, and utilities may potentially be disrupted in the affected areas. Traffic cones and caution tape have been placed to limit access to potentially dangerous areas.

Completed in 1915, the St. Mary Canal diverts water from the St. Mary River to the North Fork of the Milk River in Montana. It is a critical infrastructure component for water management in the region.

The Infrastructure Investment and Jobs Act (IIJA) earmarked $100 million to upgrade facilities that have failed in recent years, in a way that prevented delivery of water for irrigation. The funding does not require reimbursement by the Milk River Project’s water users and will be used to fund the replacement of the St. Mary Diversion Dam and Headworks.

The primary stakeholders on the project are the Blackfeet Nation, the U.S. Fish and Wildlife Service, and the eight irrigation districts that make up the Milk River Irrigation Project Joint Board of Control. Other stakeholders include over 150 pumpers along the Milk River and six municipal entities.

“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,” according to a Bureau of Reclamation press release on Monday.

According to Patrick, of the Milk River Joint Board of Control, the last time the diversion canal’s infrastructure failed was in 2020 when one of the drop structures failed. Those repairs took 22 weeks to complete, she said, which was nothing short of a miracle.

“That should have been a two-year project, and we were able to get it done in 22 weeks thanks to the cooperation of all our stakeholders,” she said. “It’s amazing what the local authorities can get done when farmers, ranchers and tribal members all combine to support the effort.”

Officials said it was too soon to determine whether a similar spirit of cooperation could streamline the repairs or replacement of Monday’s siphon failure, but Newman said the remainder of the 2024 irrigation season is at stake for a vast swath of Montana.

“These large capital project are an extraordinary burden on the water users, making replacement and repairs exceptionally difficult, if not impossible in some cases,” he said in an interview. “We’re exploring all of our options right now and actively investigating all possible solutions.”

The breach elicited an outpouring of support from Montana’s congressional delegation, including U.S. Sen. Jon Tester, the Democrat who earlier this month announced that an $88 million contract funded through the Bipartisan Infrastructure law had been awarded to Bozeman-based NW Construction, Inc.

“As a third-generation farmer, I know how critical this project is to thousands of families living in rural Montana,” according to a prepared statement that Tester released on June 6. “Montanans have made clear that replacing the St. Mary’s Dam is long overdue, which is why I made sure to secure this funding in my bipartisan infrastructure law. I am glad to see a Montana company is running this project and I look forward to seeing shovels hitting the dirt to get the dam repaired and rehabilitated so Montanans have access to the water they need for decades to come.”

On Monday, Tester wrote in a letter to Secretary of the Interior Deb Haaland and Secretary of Agriculture Tom Vilsack, “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. 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.”

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