By Jim Bloch
Signs now warn drivers of uneven pavement as they approach the section of St. Clair Highway that lays just southwest of Hillside Cemetery along the Pine River in the city of St. Clair.
“If we’re driving through town and we get to St. Clair Highway and that seawall area, the road is starting to act a little funny,” said St. Clair City Superintendent Quentin Bishop, addressing the city council at its regular meeting March 18. The CTV-Channel 6 recording of the meeting is posted on YouTube. “I know a few years back, the road started to do some funny things and there was a little bit of repair to that.”
Bishop’s comments were an unintentional understatement. He became the city superintendent in October 2022, 12 years or so after the city began spending hundreds of thousands of dollars trying to stabilize the highway.
St. Clair Highway was rebuilt in 2010. By 2011, the road surface had dropped about 30 inches and the city spent about $260,000 to build a new retaining wall near the river to hold up the roadway. The wall did not stop the movement. Early in November of that year, the city of St. Clair spent $5,455 to mill the asphalt on the sunken section, about 200 feet section, and have it replaced with crushed limestone. The city decided to keep the highway open for winter and monitor it. But the highway kept sinking and the seawall kept moving. The city closed the road completely in the spring of 2013 and it remained closed for six years. It reopened in July 2018 with troubled section left as gravel, which later was repaved.
“We have a seawall survey crew coming out this week and they’re going to be examining it,” said Bishop. “They had to get the ice off the river in order to do some depth and see what’s going on there. They’re going to be doing a survey of that seawall to see what a possible solution could be. Could it be we tack on a section of seawall and drive it in deeper? That might be one thing. Could we have a whole new section of seawall to drive in behind that to bolster up the wall? That could be an option. But the engineers are
working on that, and we’ll have some more information after the seawall crew gets back. But it’s something we definitely need to address.”
Road troubles rise as water levels drop
The sinking of St. Clair Highway appears to coincide with the declining water levels in the Great Lakes. After record highs in the 1980s, the lakes began dropping. The first decade of the 21st Century saw year after year of below average water levels, culminating in January 2013, when the lakes reached their record low.
In 2013, the city closed the highway after three years of failed fixes.
Just north of St. Clair, the city of Marysville had a repeat of bank failures jeopardizing River Road, which was reduced to a single lane running south.
Rivers exert enormous force on their banks, as much as half-pound per square inch, which increases with depth and the speed of the current. When the water level drops, the pressure on the land is removed and may cause bank movements.
The next few years were marked by heavy precipitation and extensive ice coverage, which led to the rapid rise of the water. By 2015, the lakes had risen 3.2 feet. By 2019, Lakes Superior, Erie and Ontario set all-time high-water levels, and Lakes Michigan and Huron were not far behind.
During this period, the problems with St. Clair Highway disappeared.
Now the water levels are falling again. As of February, Lake Huron was at its lowest level since 2014 and had fallen 11 inches since a year ago. It was 44 inches below its all-time high, set in 2020.
If city officials want to stabilize St. Clair Highway, they might have to find a way to raise the water levels of the Great Lakes.
Jim Bloch is a freelance writer based in St. Clair, Michigan. Contact him at bloch.jim@gmail.com.
