DOT says Hwy. 82 will be closed until testing of subsurface integrity determines safety; This Friday is latest estimate

Wisconsin Department of Transportation (DOT) officials say that cracks discovered in the roadway pavement near the Hwy. 82 slough bridge nearest the Winneshiek Slough Boat Landing entrance have resulted in the closing of Highway 82 linking Iowa and Wisconsin via the Black Hawk Bridge at Lansing until testing can be completed to determine the integrity of the subsurface and road bed of that area. The area in question is in the same location where that roadway had washed out in late May of 2017, claiming the life of Lansing resident James Walleser in an early morning accident.

Michael Bie of the Wisconsin DOT’s Office of Public Affairs for the state’s southwest region said Wisconsin DOT crews were scheduled throughout this week to conduct sonar testing underwater, along with tests requiring boring into the pavement surface and underlying subsurface which utilize small, flexible tubes with sensors to determine if there is any motion in the sand or gravel subsurface and road bed below the pavement. Bie said that officials had received reports Thursday, April 25 of an initial quarter-inch crack five feet in length further extending to over 30 feet in length, resulting in the closure of the roadway as a precautionary measure. Officials would not be able to say if the cracks were the result of natural settling of the surface that had been repaved following the May 2017 washout or due to subsurface instability until testing is completed and results determined. Officials did say that the large amount of rock that had been brought in to stabilize the area that had washed out in May 2017 appeared to still be in place and serving its intended purpose.

“We began to enact our plan to determine the integrity of the roadway when we first heard reports Thursday, it took some time to mobilize the personnel and equipment needed to conduct the testing,” Bie explained in an interview Monday, April 29. “Until we can complete the testing and determine the results, we won’t know what, if any, repairs or further action will be required, so at this point we really can’t put a timeframe together as to how long the road will be closed.”

It was released later Monday by officials that Hwy. 82 would be closed at least until this Friday, May 3.

It was previously explained by DOT officials that the high water on the Mississippi River this spring (reaching a crest near 18 feet now for the second time this spring at the National Weather Service river gauge located at Lansing) forces a greater amount of water through the constricted opening underneath the slough bridges, resulting in a higher flow velocity and sometimes the reverse circular flow of water  behind the constricting object - that phenomenon being called an eddy - that can erode away sand and other subsurface material. Bie said it’s not the integrity of the bridge itself that is in question, but instead what he called the levee on which the roadway sits as it approaches the bridge, specifically on the east end in this case.

The Black Hawk Bridge at Lansing had just been closed from April 15-21 for some planned structural repair and maintenance to that bridge itself. The Wisconsin DOT had also already been formalizing plans to have Hwy. 82 closed again sometime in late summer/early fall of this year to complete improvement projects on all of the highway’s smaller slough bridges - including the bridge where the integrity testing is taking place. Just like in mid-April and again now with the most recent situation, motorists would need to detour their crossing of the Mississippi River either 30 miles to the south at Marquette/Prairie du Chien, WI or approximately that same distance to the north at La Crescent, MN/La Crosse, WI.

“We understand the inconvenience being incurred here by area residents and travelers, but we also need to take the necessary precautions to ensure the safety of those traveling our roadways,” Bie shared. “Safety has got to be the priority.”