Traffic will move at a slower pace over two area bridges as safety upgrades are made to the structures in the coming weeks.

On Monday, crews began work to add concrete barrier rails between the sidewalks and traffic lanes on the bridge over Valley Creek on J.L. Chestnut Boulevard.

In the coming weeks, guardrails will be installed along the sides of the Medical Center Parkway.

Cornelia Sanders, project manager with Montgomery-based engineering firm Volkert Inc., said traffic would be limited, but not impossible, while the work is going on.

“We try not to shut down a road unless absolutely necessary,” Sanders said. “On something like this, they will only work on one side at a time. They might have to close one lane at a time, but the roads will not be shut down completely.”

On Monday, traffic was limited to one lane on J.L. Chestnut Boulevard as crews placed steel rebar between the roadway and sidewalk along the eastbound lane of bridge.

Sanders said the crews would be alternating the lane closures as they install the rebar and pour concrete in the coming days.

Sanders said similar temporary lane closures should be expected once work begins on Medical Center Parkway.

“While they are drilling holes, there will be lane closures, but it will just be one lane at a time,” Sanders said. “But again, the road will not be shut down.”

Sanders said both projects should be completed within the next two weeks.

“It shouldn’t take two weeks to finish both projects, but it all depends on weather, Sanders said. “They could pour the concrete for the J.L. Chestnut project this week. If the weather holds out and they can get the rebar work completed Monday and Tuesday, they could possibly pour the concrete Wednesday.”