An illegal trench dug at Big Grass Marsh before freeze-up last fall is fixed, with the province, Ducks Unlimited Canada (DUC) and Whitemud Watershed Conservation District (WWCD) picking up the tab.
Work crews hauled clay and rock to the site of the Ducks Unlimited Canada (DUC) dam north of Gladstone in early February and filled in a trench that’s been open since last October after someone rolled in with a backhoe, dug around the water control structure, and sent water pouring into the Big Grass River.
WWCD manager Chris Reynolds, who estimates the bill for the job is expected to be around $50,000, says the bigger job now is to find ways to deal with localized flooding in the area.
“We need to address the other concerns in the marsh and that includes the flooding around Jackfish Lake and specifically looking at the capacity of the channel of the Big Grass River,” Reynolds said.
“We’re going to try and get some management options together and see what makes sense.”
Jackfish Lake is the name locals have for part of the Big Grass Marsh which is Manitoba’s third-largest wetland. It recently became the province’s largest conservation project after a deal to protect the wetland was struck with the RMs of Lakeview and Westbourne, now Westlake-Gladstone Municipality.
The marsh stretches more than 40 km from south to north, and is considered not only critical wildlife habitat for geese and other birds such as sandhill cranes, but key for flood control and phosphorus retention, storing an estimated 20 tonnes annually.
The site is also an “iconic” marsh of DUC, being its first undertaken in North America in the late 1930s.
David Single, the reeve of Westlake-Gladstone, said local farmers complain it has resulted in flooding of land adjacent to the marsh. They blame changes DUC made about 15 years ago to its dam at Jackfish.
It’s more than a handful of farmers affected, Single said. “I’d say there’s 20 to 25 (affected),” said Single, who also estimates as much as 10,000 acres is affected by flooding at times.
Single said he thinks the solution is fairly simple; lowering the level of the DUC dam.
“We (Westlake-Gladstone municipality) are of the opinion that it should be an operational dam that can be raised and lowered,” he said. “Because right now it takes away from the flood mitigation that the marsh can give us. It’s too high. It’s flooding cropland. We don’t want it taken out completely. We just want it lowered a little bit.”
But DU officials say the level of the dam cannot be blamed as the sole cause of the flooding.
“I will not trivialize that land is being flooded, but you can’t point at the DU dam as being the entire problem,” said Rick Andrews, DUC’s manager of provincial operations.
“We need to understand all the factors that are going into the problem of flooding that land.”
During eight of the years, between 2005 and 2015, Manitoba had higher-than-average rainfall, and that, along with more drainage activity to the west, which is bringing more water to a topography so flat it has nowhere to go.
DUC’s control structure only holds back water in dry periods, said Andrews. During wet cycles, it’s submerged. “In flood conditions, that structure has no effect on water levels.”
The dam at Jackfish Lake was upgraded in 1999 from a control structure made with logs that could be adjusted to raise or lower water levels. The structure that replaced it is what’s known as a fixed crest that allows water to come up to its level before spilling over.
The old site was regularly tampered with, said Andrews. “We’d put it (the structure’s logs) at a level we had agreements for, and beneficial to the marsh, and then no sooner we’d be gone, the logs would be out,” he said.
“What we did when we put the current structure in, was we chose a water level that was actually below our licensed full supply level. That structure is in there for the water level when we get into extreme droughty conditions.”
Andrews said DUC will continue to engage with the province, municipality and CD regarding the matter.
“Let’s look at some options,” he said. “How can we quit putting water into an already overtaxed system? Those are the questions that we have to sit down with all stakeholders and really consider.”
Reynolds said one thing to start looking at is possibly widening the control structure’s channel. The capacity of the Big Grass River channel is restricted, he said. They could see that when they were out inspecting the site prior to repairing the cut.
“We know there’s issues with the (Big Grass River) channel itself, and siltation within that channel,” he said. “That’s one of the starting points to see what we, as the conservation district, can actually take care of.”
There was also a bigger plan drafted in the 1990s to deal with flooding issues in the area and that needs to be looked at again, he added. There were several components to it.
“One was about purchasing land around the marsh,” he said. “In today’s dollars that’s not really feasible, but the other part of the plan was about doing some work within the marsh which included cleaning up the channel.
“There’s also parts to addressing the Ducks Unlimited structures,” he added.
Single said he doesn’t know exactly why the 1990s plan was shelved, but that it had something to do with not everyone in the area agreeing to a buyout.
“It was just when I got on to council,” he said. “Let’s just say there were some farmers who weren’t really in favour of that. Whether we should be trying to get that going again or not, that’s debatable.”