Traffic will be moved to the new southbound lanes from September through November.

When the bridge construction is complete, which is set for Dec. 1, drivers will have two northbound and two southbound lanes, and a dedicated left turn lane.

A bike lane and sidewalks also will be added in both directions.

At least one lane will be open in each direction on Grand. And in September, Ameren is set to do work on manholes north of the Grand bridge between Park and Chouteau avenues in the northbound lanes for about a month. A detour is expected around Hickory Street.

The Kingshighway bridge between Shaw Boulevard and Vandeventer/Southwest avenues is slated to open in spring of 2017.

Tony Zebrowski, who lives in the Southwest Garden neighborhood, said MoDOT should wait until it’s open before working on Grand.

“It shouldn’t be done at the same time. It’s too much,” he said of the traffic problems of both projects at once for drivers.