The Wonder Lake Dam spillway repairs and upgrades got underway yesterday. The contractor’s first effort was to relieve the pressure on the stainless-steel shaft that would normally allow the west sluice gate to be cranked open, and more importantly, cranked shut. This shaft had been bent just enough to prevent the west sluice gate from operating. The shaft was successfully removed today and is on its way to a local machine shop, where it will be re-straightened.
The next step is to demolish the adjacent slumping concrete and steel bulkhead structure originally installed decades ago, presumably with the intent of protecting the sluice gate shaft from damage. It is the slumping of this failed bulkhead that was exerting pressure and deforming the west sluice gate shaft. A portion of that bulkhead structure demolition was completed today, and will continue tomorrow.
Once the west sluice gate shaft has been straightened and returned to the spillway, it will be reinstalled, restoring the function of that sluice gate.
Once that is done, an engineered steel structure, attached to the concrete sidewall of the spillway, will be installed to provide new protection for the sluice gate shaft from future damage. That will complete the work on the west side.
The contractor crew will then shift to the east side sluice gate. Fortunately, the east sluice gate has remained fully functional for many years, and its stainless-steel shaft does not need any work.
However, while the existing concrete and steel bulkhead on the east side appears to still be intact and in its intended position, to eliminate the potential for its future failure and slumping, it may also be demolished, with an identical engineered steel structure subsequently installed.
The contractor is estimating that their work should be done by next Friday, barring any unforeseen issues.
Again, it’s important to note that these repairs will be largely conducted by divers. While a No-Wake zone may not be established by the MPOA, if you’re on the lake and see the contractor’s equipment on the dam, please avoid the area within 500 feet of the spillway of the lake and minimize your wake.
