MANKATO — At about 10:45 a.m. Monday, the 153-year-old Kern Bridge was lowered, the final 18 inches or so onto the piers where it may sit for another century and a half spanning the Blue Earth River and connecting Sibley Park and Land of Memories Park.
At 8:24, Cory Bienfang, Mankato’s city engineer who became an observer on Monday, announced the actual movement would begin in 30 minutes. Right on schedule, the slow process that included three cranes and, at its conclusion a tape measure, began.
This is just the next step in a process that began in February 2020, when the bridge was removed from its longtime position just five miles south across the Le Sueur River — on what is now 195th Lane. Its pieces were meticulously catalogued and stored before this year’s reassembly, and painting took place alongside the trail it now completes in the Land of Memories side of the river.
Following what Bienfang called “ancillary connection work,” including pouring concrete to connect the bridge to the raised trail, installation of wood decking, railing construction and lighting hook ups, the bridge will be opened for walking and bicycle traffic yet this fall, he said.
“You can see the green rebar kind of little domes there,” he said, pointing to the areas on the raised trail next to the connection point. “Those are expected to be poured tomorrow, and that’s what locks that bridge into place.”
Among the first non-official people on site around 7 a.m. was Tom Zernechel. He planted a chair at the back portion of an area flattened and prepared for the KEYC TV livestream that was offered to discourage others from attending. He had a bottle of water, a camera and high hopes for what he would see.
“I just like watching the heavy equipment,” the retired AMV driver said. “My uncle was a crane operator. He let me ride with him once in a while.” He said he loves watching the big equipment do its jobs.
On Monday, that included the biggest crane across the river in Sibley Park, and two others located near the bridge parallel to the trail in Land of Memories Park. At 8:55, bystanders could see the bridge, lifted by those two, start to move toward the river. By 9:06, the front end was over the water, and the crane across the river was starting to move into position to take over.
At 9:20, a two-man crew, which stopped every few feet to reclip onto a tether, worked their way to the bridge’s end. When the rigging from the other crane reached the bridge, they began the nearly 20-minute process of attaching to the new crane lines and then creating slack so the first crane could be disconnected.
At 9:48 the initial crane’s motor revved up, and the bridge — now also connected to the crane on the opposite bank — moved further across the river while remaining parallel to the ground. The movement was slow but steady, and at one point the two-man crew on the opposite pier removed the wooden fence to clear the way for the bridge connection.
In addition to the vested and hard-hatted crew in Land of Memories Park, observers could be seen across on the hillside of Sibley Mound and on Lookout Drive. Although the rising sun made it difficult to see early, by the time the bridge moved, many clouds were hiding the sun, and the day was without wind.
Jeff Johnson retired from consulting firm SEH in 2020, but he worked on the Kern Bridge project from back when it was removed from its longtime site. He couldn’t miss the completion of its journey.
“I put the plan together on how to lift it without damaging it and how to mark and store (pieces), and seal it up until it had a later use,” Johnson said. “And I’m glad it didn’t take too long until another use was found.”
Despite its age, the bridge was in pretty good condition, said Johnson.
“There were some rivets missing, some members that were a little under capacity for the use that we wanted. So with this plan, it had to have some modifications to the floor beams and a few components. But overall, it’s the original structure.”
Mankato was selected from among potential new locations in Fergus Falls, Sherburne and Watonwan County and, for a short time, Benson Park in North Mankato. Although the project cost increased from about $1.8 million to over $10 million, Bienfang said funding was 25 percent local and 75 percent from state and federal grants.
Constructing with a crane is not unique, Bienfang said, but the historic nature of the Kern Bridge is what made Monday’s installation special. While technology certainly made the process easier than when the bridge was first installed in 1873, success doesn’t come without great care and careful preparation.
“There’s still a due diligence and an expertise,” he said. “And measurements were double checked here last Friday. So, yeah, you have as much confidence as you can in planning for this moment.”
A formal opening will be held when the final work in completed on the bridge and connecting trail.