The $37.6 million Route 18 project includes widening the roadway from two lanes with varying shoulders and sidewalks to a four-lane roadway with uniform shoulders and sidewalks along a 4.1-mile stretch from Weymouth (near Route 3 at Highland Place) to Route 139 in Abington. It is expected to break ground near the end of 2015, with construction expected to last 2½ to 3 years. Approximately 215 parcels of land may be affected. A temporary bridge will be constructed so an existing bridge that carries Route 18 over railroad tracks can be rebuilt. Full story for BostonGlobe.com subscribers.