On Sept. 28, a large rock slide struck a Rapid City Fire Department truck on S.D. Highway 44 across from the city’s fish hatchery near Cleghorn Canyon. No one was injured, but the damage to the truck marked another casualty that can at least partially be attributed to the unusually wet year in Rapid City.
The South Dakota Department of Transportation is now working to ensure a similar slide doesn’t occur. By the middle of next week, DOT crews will be done grading the area at the foot of the canyon wall and installing concrete barriers along the roadway’s shoulder for about one-half mile. The barriers, Rapid City DOT engineer Mike Carlson said, are to prevent rocks from tumbling into the road and striking a car.
“We’re trying to help prevent a big accident,” Carlson said Wednesday, adding that rock slides have also been an issue in Spearfish Canyon, Deadwood, Custer and Lead this year.
“The weather plays a big part in when those rocks come down,” he said. “That’s when our biggest rock falls occur after the rain.”
Carlson said the work along S.D. Highway 44 is a medium-term solution. Long-term solutions could include building a deeper ditch at the bottom of the canyon, installing bolts into the rock wall, or draping chain link netting along the side of the wall. The DOT routinely hires someone to knock off the loose rocks, known as rock scaling, as a mitigation effort.
“We need to do that again,” Carlson said.
The project cost will be minimal as the work is part of the DOT’s normal maintenance and the concrete barriers are owned by the DOT. Rapid City spokesman Darrell Shoemaker noted the city had experienced more rock slides “than we have normally had” but said the city had made no “overtures” to the DOT to complete the project.