A more than 100-year-old bridge that links Birmingham’s northern and southern sides is being shut down to cars and trucks because of concerns over its safety.

Dedicated in 1919 to an Alabama regiment that fought in the “Rainbow Division” of World War I, the Richard Arrington Jr. Blvd. Bridge spans railroad tracks that bisect the city. But it has a weight limit of 3 tons that’s sometimes ignored, and officials decided to close it to limit further damage from traffic.

Pedestrians, bicycles and scooters can continue using the bridge, the city said in an announcement, but cars and trucks had to use detours beginning Friday morning.

A contractor is designing a replacement for the bridge, and the city is looking at how to pay for the project, officials said.