Village Board sharpens focus on designs that call for flood-control structure
Grafton officials on Monday sharpened their focus on ways to upgrade the Bridge Street dam by directing an engineering firm to prepare two bid packages for renovations.
The Village Board agreed to have Ayres Associates complete design plans for two options to bring the downtown landmark into compliance with state flood-control regulations.
The least expensive option, estimated to cost $675,140, calls for repairing both abutments, widening the spillway and adding a 20-foot-wide stop-log structure on the east side to draw down the reservoir for high-water emergencies and maintenance.
The other option, estimated to cost $812,996, calls for the same repairs plus rebuilding the west-side overlook area. That upgrade would include installing a curved overlook accessed by stairs off Bridge Street, as well as a pool with cascading water.
Both options are eligible for Department of Natural Resources grants that will defray the costs.
In a presentation to the board, Ayres engineer Chris Goodwin said both designs are expected to meet DNR flood-control standards because of the stop-log structure.
“The cost estimates are middle of the road,” Goodwin said.
Although the board did not choose an option, members said they favored the least-expensive upgrades. Several trustees also voiced concern about the appearance of the proposed stop-log structure, which calls for an overhead trolley with a chain hoist to lift the metal logs.
Referring to a photo of a similar device installed at another Wisconsin dam, Trustee Jim Grant said the equipment had an unattractive industrial look.
“It would do the job, but it’s ugly,” said Grant, who suggested using an alternative design or bringing in equipment on a walkway to move logs when needed.
Other board members concurred, suggesting removing the chain hoist could pare $15,000 from the project cost.
However, Village President Jim Brunnquell said the hoist should be retained to ensure an efficient way to operate the structure, which would have two 6-foot-deep rows of logs.
“We’ve got to have a way to lift the logs. I don’t think we should nickel and dime this to death,” he said.
“We have to be able to manage this. It’s an extension of our park system. We have to be able to manage the dam.”
Brunnquell proposed that the hoist be given a decorative look to make it more attractive and blend in with the Milwaukee River setting. Village Administrator Darrell Hofland agreed, suggesting Ayres Associates be asked to include the change in design plans that will be reviewed by the board again before they are submitted to the DNR.
As another option, Goodwin suggested replacing the stop-log structure with a split-leaf gate system that could control water levels without logs or an overhead apparatus. He said that option would add $110,000 to the project cost, which prompted board members to reject the idea.
Pending final board approval of the design options, plans call for the project to be submitted to the DNR in January. Following DNR feedback, the village would seek bids for both options in March and award a bid in April. Construction is expected to begin by summer.
In a report to the board, Village Engineer Dave Murphy cautioned members that no project changes can be made after the designs are bid out. Once bids are received, “the village will have the actual cost difference to determine which alternative would be the best,” he said.
The DNR has awarded the village a grant that pays 50% of the first $400,000 of eligible project costs and 25% of the next $800,000, up to a maximum of $400,000.
Based on the current cost estimates, the village would have to pay $431,000 of the $675,410 cost for the basic upgrades or $534,000 of the $812,996 for renovations and the enhanced overlook. Each cost estimate includes a 15% contingency fee, which Goodwin said is standard for projects of this type.
Trustee Susan Meinecke voiced concern that the 15% fee was too low, saying the actual project cost could be higher due to unexpected expenses during construction. However, Goodwin said he is comfortable with the estimate as well as with the likelihood that the project will attract a number of bidders.
“There are a lot of contractors in the area,” he said.
The village’s share of the cost will be covered using funds from its downtown tax incremental financing district, which provides revenue for public improvements.
The dam repairs are included in the 2013 village budget. The project is expected to begin in 2013 because the DNR grant is only good through next year.
In 2009, the village considered razing the dam after the DNR determined the structure failed to meet flood-control standards and had to be upgraded or removed. The razing plan was dropped after a petition drive, led by the Save the Dam Association, forced a 2010 referendum in which residents voted overwhelmingly to preserve the structure until at least 2019.
Image Information: VILLAGE OF GRAFTON officials are proceeding with plans to upgrade the Bridge Street dam, which needs to be repaired to comply with state flood-control regulations. Preliminary designs for two upgrading options are being finalized and are expected to be submitted to the Department of Natural Resources for approval in January. Ozaukee Press file photo