The deteriorating historic Main Street Bridge over the St. Joseph River in Niles will be replaced within the next four years.

Although the design and aesthetics of the bridge are yet to be determined, Michigan Department of Transportation (MDOT) officials do know it will be in a slightly different location.

Jason Latham, planning manager for the MDOT Southwest Region, told the Niles City Council Monday night that the west end of the bridge will be shifted 10 to 15 feet to the north.

“We wanted to get an alignment that wouldn’t impact the park and historical buildings,” Latham said. “This is pretty much the only spot we can put the bridge and not have much of an impact.”

He also said sidewalks on the bridge will be at least 6 feet wide rather than the current 5-foot width.

Council member Bruce Williams asked if MODT would consider putting a barrier between the sidewalk and the road to protect pedestrians.

Latham said the extended width of the sidewalks and a 3-foot shy distance will help with those safety concerns.

MDOT officials will hold a public meeting today from 4 to 7 p.m. at the Niles City Council Chambers, 1345 East Main St., to get public input and field questions on the bridge’s alignment, historic considerations and proposed detour plans.

MDOT is currently in the environmental stage of the project, and Latham hopes that will be complete by the end of the year. The design phase will follow, which typically takes two years, according to Latham.

“We’re hoping we’ll start 2013-2014 for construction,” he said.

Latham estimates the construction will take 10 to 12 months. During that time the bridge will be shut down, and there will be a detour.

Before that, MDOT will host another community meeting this fall to discuss the “fun stuff,” Latham said.

“That’s where we kind of get the colored pencils out and get people talking about what they want it to look like — what are the aesthetics, what are the treatments?,” he said. “We can get creative.”

The 91-year-old bridge was rehabilitated in 1996 but scouring of the bridge has continued.