Post-Gazette.com – Beginning today, the southbound side of the Birmingham Bridge will close to traffic to begin preservation work. All southbound traffic will be shifted into the northbound lanes. The new configuration will consist of two northbound lanes and one southbound lane. Additionally, all bicycles and pedestrians will use the barrier protected northbound side of the bridge. The on-ramp from Forbes Avenue to bridge will close, as will the southbound sidewalk. Detours will be posted. Also, a section of Forbes Avenue will remain closed through March 18, so the Pittsburgh Water and Sewer Authority can install a new 20-inch main on Forbes. Forbes is closed from South Craig Street in Oakland to Morewood Avenue in Squirrel Hill. Crews have been working since the water main ruptured on Feb. 27.