Optimizing maintenance down the road

Illinois has one of the largest road networks in the U.S. with 147,098 roadway miles, according to the Illinois Department of Transportation, of which 2,580 are unmarked, or not designated as interstate or U.S. or state highways.

Illinois Center for Transportation and IDOT seek to maintain these roadways optimally in a joint project, “R27-240: Development of Potential Strategies for Unmarked and Low Traffic Volume Roadways in Illinois.”

Arudi Rajagopal, president of INFRAME, led the project along with Laura Shanley and Tim Peters, IDOT’s maintenance support engineer and local policy and technology engineer, respectively.

Their goal? To better understand unmarked roadways under IDOT jurisdiction and to identify candidates for possible jurisdictional transfer. 

“Marked highways are designated by a highway number while unmarked highways carry no signage, yet their maintenance is IDOT’s responsibility,” Rajagopal said.

“Going forward, the State is addressing each of these unmarked routes to classify and recommend what to do with them — one possible option being to transfer to local jurisdictions,” he added.

Jurisdictional transfer is the process of transferring ownership of a roadway or structure from a transportation agency to a local one like a city or county.

Benefits of this process include cost-savings for IDOT as well as better maintenance and service for roadways.

“The most important challenges in initiating jurisdictional transfer include the current condition of highways/structures and financial assistance available from IDOT for future maintenance/upgrades,” Rajagopal said.

To assist IDOT with identifying potential candidates for jurisdictional transfer, Rajagopal’s team gathered data from four IDOT databases to locate unmarked routes in Illinois.

They built a database of Illinois’ unmarked routes that also contains aerial snapshots of the segments and compiled it into a user-friendly tool, JARM.

JARM allows users to identify potential candidates for jurisdictional transfer based on key variables such as amount of traffic, length, and condition, among others.

They discovered that 90% of unmarked routes in Illinois are potential candidates for jurisdictional transfer.

The researchers also surveyed state transportation agencies on how they manage unmarked routes as well as local agencies on their current maintenance practices and their willingness to accept a potential jurisdictional transfer.

Some local agencies were willing to accept jurisdictional transfer, but the process is likely to vary from agency to agency.

Rajagopal’s team recommended that IDOT develop a good understanding of the needs of local agencies as well as establish a transfer fund.

“When the unmarked routes are transferred to local agencies without a maintenance agreement, the local agencies become liable for the maintenance and, as such, it improves the safety of the drivers,” Rajagopal said.

“IDOT will likely benefit from the jurisdictional transfers in reducing the overall cost of maintenance,” he added. “However, more effort is needed to evaluate the actual cost-benefit of this entire process.”

Changes are already underway in Illinois, as IDOT has begun rolling out the recommended policies.

“IDOT is looking forward to working with its local partners to begin implementing the recommendations of this research project,” said John Senger, IDOT’s Bureau Chief of Research. “IDOT’s pavement policy committee has already begun implementing some of the recommended treatment policies for low-volume unmarked routes.”