Traffic on the southbound side of the Birmingham Bridge will be reduced to a single lane tomorrow, the Pennsylvania Department of Transportation announced.

The closure will occur from 7 a.m. to 3 p.m. from the Forbes Avenue on-ramp across the southbound side of the bridge. The closure is needed to allow crews to pour concrete from the bridge into a new pier cap underneath. Brief traffic stoppages also may occur.

PennDOT is replacing the pier and column on the southbound bridge that shifted on Feb. 8, 2008. A new neoprene bearing system will be installed. Work is expected to be completed this spring.