MARSHALL — Reconstruction on College Drive isn’t the only highway project coming in the Marshall area in May. The Minnesota Department of Transportation is also preparing to resurface two bridges near Green Valley – a project that will involve a detour.

MnDOT representatives were on hand to answer questions about the Green Valley project at Wednesday’s open house in Marshall. MnDOT engineer Alan Setrum said the surface, approach panels and guardrails on two bridges on Highway 23 near Green Valley will be updated.

A detour for the construction should be up by May 12, Setrum said. Highway 23 will be closed between Marshall and Cottonwood, MnDOT materials at the open house said. Traffic on Highway 23 should take Highway 19 and Lyon County Road 9 instead.

The two bridges being worked on cross the Redwood River and Threemile Creek near Green Valley. They are located a little over 4 and 6 miles north of Highway 19 in Marshall, respectively.

Setrum said MnDOT will be removing an asphalt overlay on the two bridge decks, and making repairs to the concrete underneath. The new bridge decks will be concrete, he said.

The two bridges are both more than 40 years old, Setrum said.

Setrum said the goal for the project is to have the bridge work completed in August.