Unexpected finding will delay completion of Route 83/Winchester Road project
An unexpected find has delayed the scheduled reopening of sections of Route 83 and Winchester Road in central Lake County and added substantial cost to a long-sought road improvement.
A lengthy, monthslong detour of Route 83 between Peterson Road in Grayslake and Route 176 in Mundelein was to have ended last week.
But the discovery of more poor soil than expected means correcting the dangerous intersection of Winchester Road and Route 83 will require additional work.
As construction progressed, an unexpected issue arose on Route 83 on the south leg of the intersection, according to Shane Schneider, Lake County engineer.
“They discovered some additional unsuitable soil that was not discovered until they excavated the existing pavement of the roadway,” he explained this week to a county board committee.
Addressing that situation means driving 2-foot diameter columns of stone encased in plastic about 20-feet deep to provide stability for the road add about $1.29 million to the overall project cost.
Winchester Road is a county road that ends at state Route 83 and intersects at an oblique angle at a stop sign. Correcting that involves realigning Winchester to meet at a 90-degree angle, installing a traffic signal, turn lanes and related work.
Realigning the problem spot had been on the to-do list for several years before the county board in August 2024 awarded a construction bid of about $3.27 million.
The project area was known to contain peat, a soft organic material, at varying depths. Peat swells and shrinks and is not considered a stable road foundation.
Borings were done during the design process to determine the limits of poor soil, Schneider said. The testing followed certain spacing for the borings specified by the Illinois Department of Transportation.
The subsequent bid packages available to construction contractors specified a certain number of cubic yards of bad soil and a number of piers to be installed, according to Schneider.
The unexpected area discovered during construction will require significantly more work to address, he added.
The original agreement called for the county and state to split the project cost. Schneider said IDOT has verbally agreed to contribute another $1 million to cover added costs.
Schneider said the project is 75% complete and is expected to be finished by the end of the year.
“We will do everything in our power to make sure that happens,” said Matt Mitchell, LCDOT’s resident engineer for the project.