Avon Mountain was closed in the area of Mountain Brook Road because a tree was down on wires.
Just before 3:30 p.m., officials said one lane of the road will soon open in both directions to ease congestion. The road is now clear.
Mountain Brook Road is a loop, so traffic was rerouted from one end of the road to the other while crews work to remove the tree.
An NBC Connecticut crew at the scene said there was no backup as of 4 p.m.