October 22, 2019 – After weeks of battling rainy conditions, today Cook County announced a delay in the reconstruction of CSAH 18 (South Shore Drive).

Appearing at this morning’s county board meeting, Highway Engineer Krysten Foster said, “Most projects can withstand a rainy spell followed by a stretch of warm sunny weather, but we haven’t seen the second half of this equation to recover from last month’s rain.” Additionally, the contractor encountered significantly more rain days than is reasonable to expect during a typical July through September.

According to Foster, the Highway Department considered the value of the work, weather, and impacts to residents before deciding to delay paving. “I can’t recommend placing $650,000 of blacktop over wet gravel,” she said, “and the typical long-range forecast does not provide sufficient days to finish the dirt work and pave this road after it dries up.” After road conditions improve, the contractor needs six to ten days of favorable weather to complete paving, shouldering, and striping.

A secondary factor impacting the construction delay is the discovery of more poor soils than expected. Crews excavated approximately 15% more clay and peat than planned.

According to Foster, Cook County minimizes this risk by contracting a drilling rig to take sporadic soil samples in advance of construction projects. Even so, it’s not unusual to encounter unexpected soils between locations where samples were taken
.

“In 2016, the Highway Department ordered 32 soil borings along CSAH 18, but keep in mind the drilling machine is only a little over six inches in diameter. We knew what to expect where soils were analyzed during the design phase, but the risk of encountering poor soils remained underneath a good part of the road,” said Foster.

KGM Contractors, the company under contract for the CSAH 18 reconstruction, will focus on getting the road prepared for winter in the coming weeks. Additionally, Cook County will monitor the need for dust control next spring until South Shore Drive is paved.

The Highway Department plans to revisit standard procedures in advance of future projects to determine if scheduling assumptions or design procedures should be modified to further minimize the potential for project delays. Residents with questions are invited to contact the Highway Department at (218) 387-3014.