Malletts Bay Avenue will be closed for nearly two months starting July 18 to allow the town of Colchester to rebuild a 150-foot culvert that allows Moorehouse Brook to flow under the road.

The 5-foot diameter culvert is buried 20 feet below the road near the Colchester/Winooski town line, according to project manager Kevin McAleer.

The depth, plus the steep slopes on either side, make road closure the only option, he said. The existing culvert is falling apart, McAleer said, and sinkholes develop after heavy rains.

The road is the primary connection between Winooski and the Malletts Bay area. A detour will take cars around the project using Route 7 and Blakely Road.

“If you are in an automobile, you are not going to be happy about it, but you can make it around,” McAleer said at last Tuesday’s selectboard meeting.

Message boards announcing the closure went up this week. Detour signs were planned for Monday. The town sent letters to approximately 200 residents living in the neighborhoods around the project.

Emergency service departments will receive a private bypass around the project through the Whitcomb quarry off Route 7, McAleer said.

“It will be up to EMS to decide if they want to use it,” he said.

The contractor, S.D. Ireland, will keep a pedestrian route open around the project site. The road is expected to reopen Sept. 9.