THUNDER BAY — A treasure hunter equipped with a metal detector went to Boulevard Lake on Tuesday looking to find valuables revealed by the receding water.
The lake has been draining rapidly since Saturday when wooden stop logs at the top of the dam were removed.
It will take a few more days to reduce the level enough to allow crews to put a coffer dam in place on the upstream side of the dam, in order to allow them to make repairs without working in water.
Concrete Walls received the $7.3 million dollar contract from the city, which is also paying $1.3 million to a consulting engineering firm.
City project engineer Mike Vogrig said draining the lake had to wait until after June 20, when the fish spawning season usually ends.
Once the water is down to the Current River's normal, relatively narrow course, sometime over the next few days, the contractor will build a temporary dam out of rock fill and large bags filled with sand.
Vogrig said the water level will then slowly rise up again but not to the point it usually is in the summer months.
He said it's important to maintain the lake at a certain level because "it provides some environmental mitigation, having water in the basin rather than leaving it dry the entire summer."
The contractor hopes to complete the repairs on the lake side of the dam this year.
It's been rehabilitated in the past, but parts of the 100-year-old concrete structure are "in pretty rough shape," Vogrig said.
The city is taking advantage of the shutdown of the walkway over the dam to make other improvements including widening it, and upgrading the lighting.
It will take until the end of 2021 to finish all the work, but if things go according to plan, it won't be necessary to keep the lake level down beyond this year.
"There's quite a compressed timeline, a lot of work to get done while the water is low. That's probably the biggest challenge, to meet that schedule," Vogrig said.
Although conditions on the lake side of the dam should return to normal for next summer, allowing beaches to reopen, work on top of the dam and the downstream side will continue for another season.
The project also includes the installation of mechanical gates to improve the operation of the dam, and removal of the gatehouse at the north end of the dam that contained some equipment required in the past for power generation.
The gatehouse will make room for a viewing area with benches.
About 40 per cent of the cost is covered by a grant from the federal Disaster Mitigation and Adaptation Fund.
For Vogrig, it's rewarding to see the project finally underway after a series of delays.
He began working on plans for the restoration of the dam a dozen years ago, in 2008.
"It's good to get it started," he said.
