Viewer video and pictures showed cars wading through flood waters downtown, and officials said the construction zone on State Street started to wash away.
Steve Smith, the assistant director at Bangor Public Works, said heavy rains pushed some construction equipment into a hole in the street around 1:30 p.m., after rain washed the gravel away.
That caused a detour at the intersection of State, Exchange, and Harlow Streets, temporarily backing up traffic Thursday afternoon.
Smith said there were "six to eight inches of gravel all along State Street...didn't stand a chance against that rain."
Fire officials in Kenduskeag said a possible microburst hit the area Thursday afternoon.
A first lieutenant with Kenduskeag Fire Department said the National Weather Service was notified, to research if it was indeed a microburst.
The storm uprooted trees on Route 15. One large tree fell on Russell Jipson's truck, who lives nearby.
He said there were "severe winds and thunder and lightening, and it soon blew down a bunch of trees and I've got a tree across my pickup up there."
Utility poles were snapped in half by a farm on Route 15 in Kenduskeag.
The family that lives there was stuck behind the power lines as Emera Maine crews responded.
Across Greater Bangor, crews were left with the cleanup.
Smith said they had to "just scrape it all up, sweep it all up, and then they'll have to go to work. I'd imagine there's a lot of gravel in the sewer lines because that's what they were repairing."
There were no reports of anyone hurt during Thursday's thunder storms.