The big catch with the Duncairn Reservoir fishery assessment

A recent fishery assessment of Duncairn Reservoir and the impacts increased irrigation poses have been uncovered by the Reid Lake Property Owners Group.

Through an Access to Information Request, a four-page document created by the Water Security Agency (WSA) was released to the newly formed board just in time for Christmas. It details the repercussions a large irrigation project could have on the body of water including the life inside the H2O and how far water levels could drop.

The assessment was one of the studies about 20 stakeholders asked WSA representatives to complete in August 2023 when they met to discuss the irrigation plan being floated around.

Jeff Sereda, the manager of ecological and habitat assessment for the WSA, performed the research in September with help from some Rock Ridge Resort residents to make it around the reservoir by boat. He completed his findings in the middle of October.

"When you delve into it, I find it's more alarming than what we even anticipated," Dwight Lemon, the co-chair of the Reid Lake Property Owners Board, said was his initial reaction to the report. "The drawdowns will be considerable and the drawdowns to the CDL level will be happening almost 50 per cent of the time [or every other year]."

The report shows water levels could drop between .55 and .9 metres (or 73-96 hectares of surface area) compared to baseline conditions from April to July if irrigation is approved at a +5000-dams allocation. Lemon believes if that same surface area was taken from Lac Pelletier, it would lose a quarter to half its surface area.

Walleye, northern pike, and yellow perch re-populate in the south and west arms of the reservoir from April to July and require at least one to three metres with stable water levels.

"Habitat loss equal to or greater than the median in consecutive years could be harmful to an already low productivity fishery," Sereda said.

Lower water levels over the winter months could also be detrimental to fish trying to survive. John Durbin, a former Saskatchewan Fisheries Biologist, requested in 1982 for the irrigation cutoff to be at 803.72 metres to avoid winter kill. That would ensure depths of at least 6 meters for overwintering fish which is the recommended level for prairie lakes.

"You've got potential for huge winterkills," Lemon said.

According to the report, the Fisheries and Oceans Canada (DFO) has explicitly stated reservoirs cannot be lowered to a level that impacts fish and fish habitat. Under the Federal Fishery Act, if a proponent suspects their development may harm fish/fish habitat a request for review must be submitted.

"Our concern is WSA will not follow through with Jeff's and their own recommendations," Lemon said. "What our provincial government is asking from our water resources is not sustainable. They don't seem to understand that or be concerned about it."

The Reid Lake Property Owners Board shared their concerns with Swift Current MLA Everett Hindley in November but have been unable to schedule a meeting with David Marit, the minister who's been responsible for the WSA since August 29, 2023.

"He [Marit] is our MLA under the new boundaries," Lemon explained. "He has not had the courtesy to even reply to the requests for meetings."

Sereda concluded his report with recommendations to the WSA. They include having a new bathymetry completed for a more accurate picture of the impacts on fish. He also states they should engage with the DFO on the proposed irrigation and receive their input.