Rain helps brings lake levels up, but some are still very low

Jeff Green | Jun 10, 2015

Steady rains over the last week have had an impact on lake levels, but three lakes in the Mississippi watershed system remain very low.

Gord Mountenay of the Mississippi Valley Conservation Authority has been monitoring the water levels for years, and he said this week that although recent rains have helped, Big Gull, Mississagagon and Crotch Lake remain well below the normal levels for this time of year.

Big Gull Lake, which is 28 centimetres below normal, and Mississagagon, which is 16 centimetres low, are of concern because they are popular cottage and recreational lakes.

In the case of Big Gull, which is a spring fed headwater lake, the concern has been mounting since early March. There was virtually no spring runoff because all the snow “either sublimated into the air or infiltrated the ground but never made it to the lake,” Mountenay said, and with little or no rain in April and May, Big Gull has only lost water to evaporation since that time.

Moutenay said that MVCA drew down the lake in the late fall to bring it to within a range that they have used for a number of years, and the lake has been dammed up ever since then.

“No water has been released from that lake by us since March 1, and before that it was frozen solid all winter so it did not move at all” said Mountenay.

The story is similar at Mississagagon.

“There are things we can try to do to mitigate against too much water, but one thing we can't do is find water where there isn't any.

The water level at Crotch Lake is extremely low, 80 centimetres below where MVCA would like it to be.

Since there are no cottages on Crotch Lake, its level has not resulted in complaints to the MVCA office as Crotch and Big Gull have, but since Crotch Lake is used by MVCA as a reservoir lake for the lower end of the watershed, there is a potential problem for the prime recreational part of the summer, particularly if the summer is hot and dry.

“It's pretty simple, we need more rain, a fair bit more, or we will continue to have a problem,” said Montenay.

On the Rideau system, the story is not as grim, at least as far as Bobs Lake is concerned. Bobs, the reservoir lake for the Tay River, and ultimately, the Rideau Canal, was sitting at 162.7 metres, almost 10 centimetres above the historic average. In late April, Bobs was as much as 40 centimetre below the average, so its recovery is a relief to officials from the Rideau Valley Conservation Authority.