Water level continues to drop
Declining water level in Lake Darling reflects exceptional drought conditions
FOXHOLM – It’s low and getting lower, day by day. The concern is starting to grow too.
How low the water level in Lake Darling will fall this year remains at the mercy of the elements in a year when exceptional drought has led to the drying up of countless potholes, of parched pastures, and poor crop development.
Flows in the Souris River and its tributaries this year are similar to what occurred in the “Dirty 30’s”, and it is the Souris River that accounts for nearly all the annual inflow into Lake Darling. Earlier this week Lake Darling dipped under 1,594 feet, three feet below its normal summer operating level and approaching the low mark of 1,589.5 feet set in 2008.
The water level at Landing No. 1 on the lower end of Lake Darling has already reached the point where the launching of all but very shallow draft boats is impossible. The ramp is located on a shallow gradient where the effect of low water is prominent. Two other ramps on the lower end of the lake, the Spillway Ramp and Landing No. 3, remain operational. Both enter deeper portions of the reservoir than the ramp at Landing No. 1.
Approximately 150 cubic feet of water per second has been released through the gates at Lake Darling Dam since early June. The water was necessary to meet requirements of the International Treaty with Manitoba and to provide some water for the J. Clark Salyer National Wildlife Refuge where several holding pools were dry or extremely low.
Inflow at the upper end of Lake Darling as recorded at the Sherwood gauge on the Souris River has been abysmal, mirroring a similar pattern as one that emerged in the low water year of 2008. On May 10 of that year the flow in the Souris at Sherwood was measured at a paltry 10 cfs and remained very low for the summer. Recent flow measurements of the Souris at Sherwood have been in the mid-teens or less, and that compares to a long-term average of 171 cfs.
So, with more water going out than coming in, Lake Darling continues to decline. The current mandated release is scheduled to end in the coming days, but that doesn’t mean the gates will be closed entirely.
“We’ll initiate a minor release so the U.S. Geological Survey can do a seepage study,” said Tom Pabian, Upper Souris NWR manager. “We’ve been letting water out of the refuge but only a percentage of it is getting down stream. From Baker Bridge through Minot there is an incredible amount of loss. Where is it going?”
The amount of the water to be released for the USGS study will have a minimal effect on Lake Darling. Of greater concern is how much the lake will lose to evaporation the remainder of the summer. Without any rainfall that will increase flow into Lake Darling, the impoundment could lose up to another two feet due to evaporation. If so the lake will drop somewhere in the range of 1,592 feet, putting it at high risk of winter fish kill heading into freeze-up.
Lake Darling, actually a reservoir, is not particularly deep. The narrow old Souris River channel runs through the lake, sometimes reaching a depth of 20 feet, but Lake Darling is primarily 12-14 feet deep at full summer pool level.