Feds reject temporary fix for St. Mary Canal, focus on 2025 irrigation

At a public meeting in Malta Tuesday night, U.S. Bureau of Reclamation officials told about 100 people in attendance and more than 50 watching online that the agency determined it would be impractical — financially and logistically — to implement a temporary fix for two failed steel siphon pipes near Babb that allowed the St. Mary Canal to plunge down a hillside, across the St. Mary River, up and over a smaller hill, and toward the upper Milk River to the east.

The canal and siphon are part of the Milk River Project, which diverts water from the St. Mary River on the east side of Glacier National Park and sends it instead into the Milk River, which spans the Hi-Line from Havre to Fort Peck. The siphon pipes failed June 17, hemorrhaging nearly 4,500 gallons a second and destroying the once grassy hillside they traversed. The failure broke the link that fed water from the St. Mary into the Milk for more than 100 years. 

The twisted remnants of the pipes are unusable, BOR officials said. And establishing a pumping system to push water from the St. Mary River over the hill that the siphons traversed would cost up to $3.06 million and deliver only a fraction of the water that once flowed through the siphons. A technical team including engineers and other specialists from BOR, the Blackfeet Nation, Milk River Project Joint Board of Control, Northwest Construction, Bureau of Indian Affairs and HDR engineering firm concluded after a late June site visit that such a system would be costly, complex and unreliable. 

Instead, BOR officials are eyeing a $70 million permanent replacement of the siphons, and another aging siphon system at Halls Coulee.

“Due to the time and costs associated with a temporary solution that would deliver only a fraction of normal diversions, Reclamation has decided to focus all efforts on complete replacement of the St. Mary Canal siphon and Halls Coulee siphon as expeditiously as possible,” Ryan Newman, BOR’s Montana area manager, said in a statement Tuesday. He reiterated those remarks at the meeting that night.