Any information on a stone monument with plaque affixed?
It is located off the freeway by I-75 North, just before Gratiot – there is a short spur of the freeway that connects and ends right at Gratiot – a grassy area to one side right at Gratiot.

The text reads:
“We would like to thank the workingmen and women, the “backbone,” of this project that sacrificed their personal time, jeopardized their marriages, lost precious time with loved ones, through sickness and inclement weather, constructed this project for the City of Detroit and the State of Michigan.
Original Contract Time
Phase 1 – 240 Days
Phase 2 – 120 Days
Time of Construction
Phase 1 – 118 Days
Phase 2 – 26 Days”

What would this be referring to?