THUNDER BAY – The rehabilitation of the Boulevard Lake dam will cost $1.5 million more than expected, with a report from City of Thunder Bay saying the structure was in worse condition than expected.
The increased costs are attributed to a variety of factors in the report, which will come before city council Monday for approval of additional funding.
The project was expected to cost about $8.5 million in total, before the increase, with a $7.2 million tender from local contractor Concrete Walls coming in well below the city's pre-tender estimate of $12 million.
Nearly half of the increased cost, $700,000, is attributed to the installation of new post tensioning.
“Upon removal of the deteriorated buttress concrete it was discovered that the existing post tensioning for the dam was unsalvageable and not able to be re-tensioned,” the city report reads.
General overages were also attributed to the deteriorated condition of the structure.
“Overall the dam was generally in a poor state of repair,” the report states. “Often times the concrete removal limits had to be extended, go deeper than expected, or resulted in unsalvageable steel. Increased costs included additional concrete removal, additional concrete, and additional reinforcing steel.”
A number of other factors drove smaller increases, the city said.
That included $200,000 for removal of bedrock that was higher than expected at the base of the dam, resulting in new mechanical gates not being able to open fully.
Another $200,000 is associated with repairs of the intakes to the small hydro generation plant below the dam, which the city said was necessary to comply with a provincial permit to take water.
Repairing the intakes during construction avoided “significant additional cost in the future,” with the city eyeing the potential to once again generate power at the site.
Another $200,000 in additional expenses was chalked up to cold weather work, with temperatures dipping earlier than usual in October, and additional work approved that extended year one work on the structure into March.
Heritage costs contribute another $220,000 to the overrun, with an archaeologist deeming a wooden weir structure at the site historically significant, requiring additional protections.
Plans for a viewing area with seating and information plaques reusing materials from the original dam, designed in discussion with the city’s heritage advisory committee, are expected to cost $160,000, an additional $120,000 above the contract allotment.
The contract is still scheduled to be completed on time at the end of October, the city said.
Staff also noted the $1.5 million in additional costs are projected and could still change.
The additional funds required are available from a municipal capital carry forward budget, the city said.
The rehabilitation project was funded about 40 per cent by the Federal Disaster Mitigation and Adaptation program.
City staff were not immediately available to comment on the increase.
