County to remove failed dam
A dam that failed during the storms on Father's Day weekend is likely to be removed from the Cranberry Creek in Oakland.
Douglas County's Forestry Committee decided to remove the Cranberry Creek dam rather than repair or replace it.
The dam, which was constructed in 1973, is an earthen dike with concrete abutments, and functions like a permanent spillway when water rises above the weir, Forestry Manager Jon Harris said. He said while the county made some improvements to the dam three or four years ago.
What happened is the water got so high that it overtopped the weir structure and started cutting out the earthen dike east of the weir and blew out the whole dike, Harris said. He said the weir was damaged as a result of the water movement.
As owner of the dam, Douglas County was obligated to report the failure to the Wisconsin Department of Natural Resources as a failure.
The state issued an order demanding Douglas County remove, replace or repair the dam with a Sept. 1 deadline to come up with a solution.
"If you make a decision to remove it, under the current order, I have until Nov. 1 to get a plan to them on how we're going to remove it," said Mark Schroeder, parks and recreation manager for the county. He said the state could take up to a year to approve that plan.
Estimated cost for repair was $70,000, and $160,000 to replace it, Harris said.
"These are very, very rough estimates," Harris said. "There are some grant moneys available for some of these, like removal, as well as possible for some of the repairs."
Harris said the dam is considered a low hazard. Most of the property around the dam is owned by Douglas County, and is used primary for recreation.
"From the department's perspective, we understand the recreational benefits, the ecological benefits, but knowing how funding is in the county, and knowing how these dams are increasing costs over time, that our recommendation would be to go the removal route here," Harris said.
"I don't know what our liability would be, but I imagine if we rebuild it, there would be some liability," Douglas County Board and Forestry Chairman Mark Liebaert said.
"Lucky for us, this is the only dam we're talking about," Harris said.
"The trend is to remove dams unless they are generating power or building tax-based," Schroeder said.
The committee approved a motion to remove the dam and apply for funds to pay for the removal.