FOR IMMEDIATE RELEASE Contact: Dustin Earley
Phone: 517.482.1189
Email: dearley@micountyroads.org
Road Commission of Kalamazoo County uses aggregate “lift” to fix underwater road
Normally to get to grandma’s house you go over the river and through the woods, but for the past year in Kalamazoo, it has been under the pond and through the flood.
Since July 14, 2019, Kalamazoo’s 8th Street in Oshtemo Township had been underwater due to flooding from a nearby pond. Last September, the Road Commission of Kalamazoo County (RCKC) deployed an innovative aggregate “lift” to remedy the problem.
The road is nestled between two hills in a valley-like area, giving the pond no outlet. Without an outlet, traditional ways to fix the road flooding were not an option. An engineering firm estimated that a fix would cost RCKC $1.8 million for the 500-ft. stretch of road.
With the engineering company’s estimate way past affordable, RCKC began to explore their options. They came up with a solution, the “lift,” that would only cost about 11% of the proposed million-dollar-fix.
Equalizer and the Critters
The first step to the solution was ensuring the road would have two adequate culverts installed: An equalizer for the water and a “critter crossing” for wildlife. RCKC worked with the Michigan Department of Environment, Great Lakes and Energy with determining the specifications for culvert installation.
Next, RCKC used multiple layers of guardrail on either side of the road along with multiple layers of geotextile fabric inside the pavement to keep the materials intact. In order to reach their desired elevation, RCKC added aggregate which was reinforced with cables running from either side of the road.
Finally, RCKC added approximately four inches of hot mix asphalt and finished the project with riprap on the shoulders and fresh pavement markings. The road is now three feet higher and well above water levels.
By using the aggregate lifts, RCKC saved taxpayers $1.6 million.
The project was unlike any of the others RCKC has done, but they drew upon knowledge from several other projects.
“In addition to performing work underwater, the footprint of the road was fairly narrow, so it made the design process a little more challenging,” said Elli Blonde, RCKC communications administrator. “We also hadn’t stacked the guardrail on the other roads like we had for this one. We were able to take what we’ve learned from the other projects to make this one even better.”
For county road agencies interested in implementing this process, RCKC project engineer Rebekkah Ausbury suggested they examine the footprint of their road because aggregate lifts aren’t effective for longer stretches.
“There was a lot of intricate work that involved smaller equipment, which takes more time,” Ausbury said. “It’s important to be mindful of surrounding topography and to blend the new elevation for a smooth ride. Because this segment of road was nestled in between two hills, we had to make sure the approaches on either side had smooth transitions.”
Despite the challenges faced, the aggregate lift process proved a worthwhile solution for RCKC.
To learn more about RCKC’s journey to fix their underwater road, read the winter issue of Crossroads magazine, the quarterly journal of the County Road Association (CRA) of Michigan, which can be viewed digitally or downloaded at https://micountyroads.org/newsroom/crossroads/.
The 83 members of the County Road Association of Michigan represent the unified voice for a safe and efficient county transportation infrastructure system in Michigan, including appropriate stewardship of the public’s right-of-way in rural and urban Michigan. Collectively, Michigan’s county road agencies manage 75 percent of all roads in the state, including 90,000 miles of roads and 5,700 bridges. County road agencies also maintain the state’s highway system in 64 counties. Michigan has the nation’s fourth-largest local road system.
