Conestogo Lake dam work means lower water levels in reservoir this summer and fall

Work on the damn in Conestogo Lake means water levels in the reservoir are expected to be below normal at times for the rest of the summer and into the fall.

The Grand River Conservation Authority (GRCA) says comprehensive rehabilitation work on the dam is ongoing this summer, part of a multi-year project to repair damage to the dam caused by weather and ice. The dam, located northwest of Elmira, was built in 1958 and is used to reduce the impact of flooding.

Over the next few months, workers will be on barges in the reservoir to repair concrete on the upstream wall of the dam, the GRCA said. As well, to accommodate the work that needs to be done, water levels in the reservoir will be lowered "at a faster rate than is typical for this time of year" to allow workers access to the wall, the authority said.

"The dam will continue to operate as intended throughout the duration of the project and provide its primary flood storage and flow augmentation functions," GRCA said in a statement on Tuesday.

"Cottagers and recreational users of the Conestogo Lake reservoir should expect fluctuating water levels as a result of this work. During the summer months of July and August, the reservoir level may drop by up to 20 cm per day."

After Sept. 2, the reservoir levels could drop by up to 30 cm in a day, the authority said. The work is expected to continue into December.

The GRCA says there are no expected impacts to fish within the lake. The beach and boat launch at Conestogo Lake Conservation Area may be out of service earlier than usual.

Rehabilitation work on the dam is expected to be completed by the end of 2025.