Courtesy photo A large hole that opened on U.S. 2 in Manistique is pictured Tuesday evening. The hole has since been filled in temporarily.

MANISTIQUE — The Michigan Department of Transportation (MDOT) has established a detour after a large hole — about four feet deep and six feet in diameter — opened on U.S. 2 in Manistique earlier this week.

MDOT Communications Representative for the Superior Region Dan Weingarten said MDOT was notified of a depression in the highway’s pavement at about 9:30 p.m. Monday. The department shifted traffic so it would avoid this section of pavement.

“Shortly before 5:30 p.m. Tuesday, we were notified that the pavement had collapsed and this hole had opened up,” Weingarten said.

The hole, located on the eastbound lane of U.S. 2 just west of the bridge in Manistique, was about three to four feet deep and about six feet in diameter.

“It has now been filled in temporarily until the sewer repairs can be completed,” Weingarten said.

The collapse was caused by fill material under the highway eroding and being carried away in the broken main sewer transmission line for the northwest side of Manistique, which has been in place since the late ’20s or early ’30s. This loss of fill material left a void under the highway.

“We’re going to do a directional bore with a new pipe,” Water/Wastewater Superintendent Corey Barr said of plans to replace the line.

Replacement work is expected to take about a week to complete.

“We anticipate boring the new hole Saturday or Sunday, and then pulling the pipe through Monday or Tuesday,” Barr said.

Efforts are also underway to set up a temporary bypass that will be used during the switchover from the old line to the new line.

A detour has been put in place for drivers traveling eastbound on U.S. 2. The detour, which Weingarten said adds about 1.4 miles to the route for eastbound drivers, takes motorists onto Chippewa Avenue and M-94 before returning to U.S. 2.

Since the sewer transmission line has not fully collapsed, Barr said the city’s sewer system is still functioning. However, there have been some issues related to sand intake.

The official cost of replacing the sewer transmission line has not yet been determined.

“At this point in time, I don’t really have a solid estimate that I’m willing to put out there,” Barr said.

However, he noted it will likely not be cheap.

While work continues on U.S. 2, Barr urged drivers in the area to be cautious.

“Drive carefully and follow the signage,” he said.