The warning had been in place for a long time: The 100-year-old St. Mary River diversion system was likely to fail at any moment.
On May 17 it happened.
A concrete structure on the St. Mary Canal near Glacier National Park crumbled and washed downstream, shutting off flow to the Milk River and leaving the entire northern hi-line of Montana without a stable water supply, including 140,000 acres of irrigated crops on over 700 farms and affecting 18,000 people in the Milk River basin.