West motorists should be alert for detours and lane restrictions during these highway improvement projects:

McKees Rocks Bridge -- The McKees Rocks Bridge will be closed from 12:01 a.m. Saturday to 6 a.m. Monday during concrete repairs, sawing and sealing joints and dams, replacing strip seals, caulking barrier, repairing barrier and roadway spalls, removing temporary barriers and painting.

Route 18 (Wallace Run Road), Beaver Falls, Big Beaver, Homewood, Koppel -- A $2.8 million project to mill and resurface, improve the shoulders, update the traffic signals, repair a bridge and perform other work will mean single-lane traffic through this month. The overall project is expected to be completed in June.

Dorrington Road, Collier -- Work is under way to replace the 121-year-old, single-lane, single-span Dorrington Road Bridge over Robinson Run between Cluxton Street and Noblestown Road. The 60-foot wrought-iron pony truss bridge built by the Pittsburgh Bridge Co. will be replaced with a $1.4 million concrete box-beam bridge with two lanes and improved approaches and sight distance. The detour is Hilltop, Walkers Mill and Noblestown roads. Work will continue through April.

Beaver Avenue, Monaca -- The intersection with Route 51 has been closed as part of an $8.5 million bridge replacement project, which will continue through April. Access will be provided for local businesses and residents. The detour is 14th Street.

Route 51, Monaca -- Lane closures and other restrictions will be in place from 7 a.m. to 3 p.m. daily during an $8.5 million project to replace the bridge that carries Route 51 over railroad tracks about one mile south of the Ohio River between Beaver Avenue and 21st Street. The project includes replacing the bridge over the railroad tracks; bituminous paving; new bridge approach slabs; upgraded drainage; guide rail, curb and sidewalk replacement; sanitary sewer line and waterline relocations; and other improvements. The project is scheduled for completion in fall 2010.

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