Natural flow only on the Milk River for rest of season as replacement work continues on diversion system
It’s been two months since the taps were turned off for the Milk River because of a major breach to a diversion system that redirects water from the St. Mary’s River in Montana into the Milk River.
It was on Sunday, May 17, in the midst of the long weekend when Drop 5 (a concrete drop structure) of the diversion system, the final drop of the system before the water reaches the North Fork of the Milk River, collapsed. The result has been a significant drop in water supply through the channel that winds through Southern Alberta.
In fact, what people are seeing now are natural summer flows that have not been seen in 105 years when the system was built.
“Normally 18 cubic meters per second flow. Now, the Milk River is at less than one cubic meter per second, so one-eighteenth of what we normally see,” said Tim Romanow, executive director for the Milk River Watershed Council.
When the damage occurred, the canal was flowing at approximately 200 cubic-feet-per-second and canal flows were immediately turned off. All parties involved agreed immediately on May 17 to replace Drop 5, as well as Drop 2.
Along the Milk river are 40 farm families who are independent water license holders andre lyon that water for irrigating their crops .8,200 acres are irrigated using water drawn from the Milk River. In addition, three municipalities, Milk River, C out ts, and Sweet Grass rely on it for use in their communities. Fortunately, all three have plenty of supply to last through the summer months, but have outdoor water restrictions in place.
“The three municipalities have three to four months supply. Their reservoirs are fairly topped up,” he said.
Another saving grace for the region has been the abundant rainfall over the past several weeks.
“We have been really lucky to this point because of all the rain, but right now, we’ re trying to keep up with the demand. Rain is the only thing that’ s kept it going ,” said Roma now, noting that one storm dropped five inches of rain, benefit ting the growing crops.
The forage, cereals, and oil seeds are all looking pretty good. They won’t have to worry about getting hay this year,” he said.
The water system is part of the US Bureau of Reclamation’s Milk River Project St. Mary Canal and is located northwest of Cutbank on the Blackfeet Reservation. The Drop 5 concrete drop structure is the last of five drop structures that use gravity and siphons to convey water through the 29-mile long St. Mary Canal to the North Fork of the Milk River. Water is diverted into the canal from the St. Mary River, near Glacier National Park.
Repair work was a daunting task initially until politicians on both sides of the border stepped up.
“The drop is at a remote location near Whiskey Gap, then there’ s 20 miles of trail on the Black feet Reservation to get to the site, so the turn around time for the trucks wasn’ t good ,” said Roma now. “They wanted to get permission from Border Services to use E migration Gap and haul aggregate from the Cards ton area rather than via much further distance sin Montana. This would save us 20 percent in the budget and time with the schedule.”
M LA Grant Hunter and MPG len Motz lobbied the provincial and federal governments in Canada, while their American counterparts did the same on their side.
“Both federal governments allowed us to use that route in order to get that aggregate in,” said Romanow.
As the construction work continues south of the border, the Milk River Watershed Council and other agencies, including Alberta Environment and Parks, are monitoring and researching the impacts to the flora and fauna, as well as the current water quality.
“There are algae blooms because of low flow rates, high temperatures, and higher amounts of nutrients such as nitrogen and phosphorus. Normally, there is bentonite in the water that prevent sUV light from penetrating. Now, there is a lot more water clarity,” said Romanow.
“Researchers, volunteers, and cameras and documenting the situation including wildlife patterns and fish mortalities. For instance, the pronghorns are changing their path,” he said.
Water users in the area are also submitting weekly reports to the
Watershed Council for analysis.
“This also gives us the opportunity to plan for long-term water issues, such as storage ,” he said .“Whether you like it or not, climate change is happening, so this has been for learning and to get our ducks in a row. At least we’re getting through this year.”
Romanow said the earliest the construction work will be completed is at the end of September, but the taps likely won’ t be turned back on until next year.
It is estimated that it will cost 4175 million to fully update the diversion system, with their riga tor sin Montana being on the hook for 75 percent of it.