Below, the highway under the bridge was also closed in both directions, Fox 2 reported.
There was nothing unusual about any of this.
It's routine to shut down the roads when someone threatens to jump.
But at some point, while police continued to talk the man on the bridge, a semitractor-trailer rig crept past the barricade on the interstate and pulled to a stop directly beneath him.
A second rig joined it. Then another, and another.
Onlookers started to film as they formed a sort of bridge beneath the bridge - a safety net of metal to break any fall.
Michigan State Police were organising this, a lieutenant later told AP.
It wasn't the first time they used truckers to stop a suicide, he said, but it was unusual to see so many volunteers.
When the last 18-wheeler pulled up under the Coolidge Highway bridge sometime before sunrise, there were 13 of them in total. From one wall of the interstate to the other, it was nothing but rigs, their roofs just a few feet shy of the bridge.
The whole process took three or four hours, AP wrote. By the end of it, the man who had once been alone with his thoughts had police on each side of him, talking to him, and a row of truckers sitting vigil below, refusing him his option to fall.
So the man, whoever he was, walked off the bridge and into a hospital, Fox 2 reported.
Police cleared out of the highway, and the 13 rigs and their drivers also went on their way.
Any way but down.
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• Samaritans 0800 726 666
• If it is an emergency and you feel like you or someone else is at risk, call 111.