There appears to be a debate between our lake residents as to whether increased lake water levels are a good thing. In one camp, they like the higher water level. They believe less aquatic and perhaps invasive plants are present, and they prefer the overall aesthetic. Others argue that higher levels are eroding the shoreline; more trees and retaining walls are undermined and fall into the lake. Who is right?—Michel Bourque, Val-des-Lacs, Que.
Nobody. Both high water levels and low water levels have pros and cons, says Meaghan McDonald, the lake planning/shoreline stewardship coordinator with the Rideau Valley Conservation Authority in Manotick, Ont. “And fluctuating water levels are a normal part of ecosystem functions.” It’s true that higher water levels could mean fewer plants, at least in the short term, she says. Good, if those plants are invasive. Not so good if they’re native species keeping the lake healthy. Some cottagers might find aquatic vegetation annoying, or an eyesore, but it can be vital. “Lakes often have shallow bays with lots of vegetation that is natural and important to aquatic life. If the suggestion is to raise lake levels to ‘drown out’ these areas, I would be wary,” says McDonald.
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Plus, as you mention in your question, a higher water level could cause erosion, “and I would suspect invasive plants would soon find footing along the ‘new’ shoreline,” says McDonald. A lower water level might keep a retaining wall from crumbling, but it could also have a negative impact on fish and other aquatic creatures (a drop in water alters their habitat).
From the perspective of a cottager, there might be an ideal water level for a lake—for convenience, for aesthetics. But there isn’t one from the perspective of the lake. Your lake’s not Goldilocks. There’s no “just right.”
If conflicting interests on your lake are causing friction, you might consider encouraging your lake association to implement a lake plan, with the goal of keeping the water healthy for the future. Then everyone—flora, fauna, and cottagers—will get to enjoy it for a long time. Who could debate the value in that?
Got a question for Cottage Q&A? Send it to answers@cottagelife.com.
This article was originally published in the March/April 2025 issue of Cottage Life.
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