Souris River reduced to trickle
Little flow throughout drainage
While some water was flowing over coffer dams in Minot Wednesday, the movement may slow to a trickle in the coming days.
The amount of water being released into the Souris River from Lake Darling Dam has been reduced from approximately 120 cubic feet per second to as little as 20 cfs. So far this year there has been very little flow in the Souris River Basin. Reservoirs on the system have struggled to capture enough water to reach summer operating levels.
“Grant Devine terminated releases Tuesday, based on the fact that water owed to the U.S. has been delivered,” said Tom Pabian, Upper Souris National Wildlife Refuge manager.
Grant Devine, formerly Alameda Reservoir, is located on Moose Mountain Creek in southern Saskatchewan. Releases from that impoundment flow into the Souris. Lake Darling is located within the boundaries of Upper Souris NWR northwest of Minot.
“Our releases are minimal but we hope to maintain them for the summer months to maintain dissolved oxygen levels to support the fishery in the Souris,” said Pabian. “In the heat of summer there may be only a trickle over the coffer dams in Minot.”
The Souris River, the major source of water for Lake Darling, enters the north end of the lake after flowing through what is known as the Sherwood Crossing. Flows at that location were a mere 111 cfs Wednesday and were expected to decrease based on the closing of release gates at Grant Devine.
Lake Darling stood at 1,569.9 feet Wednesday. Summer operating level there is 1,570 feet according to the International Agreement between the U.S. and Canada. The Souris, which originates in Saskatchewan, loops down through North Dakota before turning northward to re-enter Canada in the province of Manitoba a few miles north of Westhope.
Rafferty Reservoir near Estevan, Sask., which is located directly on the Souris River and connected to nearby Boundary Reservoir via a diversion channel, was at 1,802.5 feet Wednesday, about one-half foot below its preferred summer operating level. The release gates at Rafferty remain closed.
Grant Devine, near Oxbow, Sask., had a level reading of 1,840.8 feet Wednesday versus a summer operating level of 1,840.9 feet.
Flow gauges all along the Souris River remain very low, as they have been for the entire spring season. At the Baker’s Bridge gauge, the first reporting point on the Souris below Lake Darling Dam, Wednesday’s flow reading was 13.8 cfs. That compares to the long-term norm of 450 cfs. There are similarities at other reporting points.
At the Boy Scout Bridge gauge off Minot’s northwest edge there was a flow of 115 cfs Wednesday but that amount is expected to decrease as reduced flows through Lake Darling become apparent. Average flow at the Boy Scout Bridge this time of year is 486 cfs.
Other reporting points upstream from Minot also reveal how little water is in the system. At Long Creek, which flows along the northwestern border of the state before swinging back into Saskatchewan and into Boundary Reservoir, flows were barely measurable Wednesday at a scant 2.2 cfs. That compares to an average for the date of 69 cfs.
The Des Lacs River, which joins the Souris at Burlington, has carried a very limited amount of water so far this year. On Wednesday the Des Lacs at Foxholm was flowing at less than 4 cfs, far below its 66 cfs average for the same date.
Below Minot, where the Souris has the benefit of additional tributaries to supplement its flow, the numbers are equally telling. The Wintering River near Karlsuhe was registering 12.4 cfs Wednesday and Willow Creek, near Willow City, 45.6 cfs. Historical averages for those locations on the same date are 34 and 138 cfs respectively.
At Westhope, where the highest readings on the Souris can be expected, Wednesday’s flow was 476 cfs as compared to the long-term average of 1,060 cfs.
Barring significant rainfall that could bring new water into the drainage, interests all along the Souris River are preparing for what could be a year of very little water.