Sep. 17—BELLAIRE — Repairs are now in the works on the washed out section of Alden Highway at Finch Creek, where torrential rainfall last month flooded the stream and overwhelmed the infrastructure.
Cost estimates are as high as $230,000 to fix the rural highway after it collapsed Aug. 10 when culverts at the creek failed under the pressure of a severe thunderstorm’s raging runoff flow.
Officials said it’s the largest bill among Antrim County’s multiple road repairs needed after what experts called a climate change-driven downpour.
“I have seen washouts close to this, but not on a primary road like this,” said Burt Thompson, the engineer-manager for the county’s road commission.
Alden Highway is one of the most heavily traveled roads in the county, he said, so workers are hustling to repair the damages before winter arrives. The goal is to re-open by October’s end, Thompson said.
That project is just one of several needed road repairs after reportedly as much as 6 inches of rain fell during an approximately 45-minute period between Aug. 10-11 in the Alden area.
Records show about 5 inches of rain fell across other parts of Antrim County over the course of a longer, couple-hour stretch that night.
“We’re going to be pushing $400,000 in unplanned expenses,” Thompson said, explaining how other county road repairs from that night’s damages cost about $155,000. All of the unexpected bills will be covered by the road commission’s savings, he said.
The Finch Creek washout was by far the worst among the damage, Thompson said, with both 48-inch culverts blowing out and creating a 15-foot-deep washout on the main road.
“It was just so much water in such a short period of time that they couldn’t handle it,” he said.
State environmental regulators recommended the road commission install a new “bankfull-width” culvert to replace the blown out creek crossing, which had to be special-ordered from a manufacturer in Kentucky. The 18-foot-wide and 12-foot-tall aluminum structure will be pieced together in coming days and craned into place next week, the engineer-manager said.
Thompson said a contractor will be hired to repave the stretch of highway and re-install the guardrails.
A federal climatologist previously described the severe thunderstorm that wreaked havoc on Antrim County last month as a symptom of planetary climate change.
Climatologist Harold Brooks, of the National Oceanic and Atmospheric Administration’s National Severe Storms Laboratory, said changes in humidity happening worldwide will continue to exacerbate the growing frequency of severe weather events.
“Dew points have gone up because as the planet is warming, there is more water evaporating out of the oceans and that leads to more energy for storms, and more rain to fall out,” he said last month.
Among the indicators of climate change are how rainfall patterns have and continue to shift, Brooks said.
“We do know there’s an increase in the fraction of rain that happens in the heaviest rain events,” he said, adding that in laymen’s terms, it means “the heaviest rain events have become heavier.”
Last month’s severe storm over Antrim County was reminiscent of the 2018 Father’s Day storm and flooding in the Upper Peninsula’s Houghton County; there, though, upward of $45 million in damages shredded roads and washed away bridges.
“We knew rain was coming but nobody anticipated the volume,” said Kevin Harju, Houghton County Road Commission engineer.
He said that severe weather event left as many as 40 roads impassable in that southern Keweenaw Peninsula county; repairs and upgrades to infrastructure have continued since the big storm, with the expectedly final $8 million in work planned for summer 2022, Harju said.
A flash flood on June 17, 2018, washed out dozens of roads and created sinkholes across Menominee and Houghton counties, forcing some residents to move around by boat. A Houghton middle school student also died after weather-related injuries at his home.
That storm was classified as a “1,000-year storm,” Harju said, and officials opted to increase the capacity of culverts and other infrastructure to handle at least 50-year and 100-year storm runoff volumes as part of recovery efforts.
“There was a lot of upsizing of structures,” he said.
Thompson said Antrim County doesn’t currently have runoff capacity increases planned for its infrastructure upgrades because of the forecasted effects of climate change-fueled storms.
“As it seems to keep coming, I’m thinking we’ve got to change that mindset,” he said.
Houghton County officials eventually developed a severe weather disaster handbook following the destructive thunderstorm three years ago. The idea was to help other counties navigate federal funding schemes within transportation and emergency programs, Harju said.
“If another county has this happen, they don’t have to reinvent the wheel,” he said.