Lawrence city commissioners approved paying $355,000 for unanticipated repairs to Bowersock Dam Tuesday 28 percent higher than originally allotted for the project and more costs might be on the way.
"I don't want to leave you with the impression that that's all-inclusive costs, because there are still unknowns," said Mike Orth of the engineering firm Black & Veatch, which is overseeing the project for the city.
Commissioners had already approved spending $1.26 million to shore up the north half of the dam, which spans the Kansas River just north of City Hall, Sixth and Massachusetts streets.
But additional inspections revealed that portions of the south half of the dam are insufficiently supported and have even eroded in some spots, threatening the dam's stability.
"Now that we're into the project and the river's down, we see what needs doing," Mayor Mike Rundle said.
The causeway that has been built partway across the river to hold equipment for the project must be extended to accommodate the repairs, Orth said. That's the biggest portion of the additional cost, he said.
"The fix is easy," he said. "Getting there is the cost associated with it."
Orth said he couldn't guarantee the work wouldn't be hampered by winter weather, which would add to the project's cost.
City officials grudgingly approved the additional expense.
"I've not been happy with the cost, for sure, but this is a rare opportunity we're not in a position to make this kind of fix very often," City Manager Mike Wildgen said. "We're in a position to fix it for 50, 60 years."
J.D. Bowersock completed the dam in 1874, and it has undergone several rehabilitations since. City officials say the last major project was done during the 1970s.
Although the dam is owned by Bowersock Mills and Power Co., the city is paying for the project because the dam slows the river enough upstream to allow intake of water at the Kaw River Treatment Plant.
"There are some fairly serious-looking problems down there," Commissioner David Dunfield said. "Once we've started a repair, we might as well finish it."