ALLENTOWN - Work will begin Dec. 27 to replace the Locust Ridge Road (“Thornhurst”) Bridge over the Lehigh River located in Coolbaugh Township, Monroe County and Thornhurst Township, Lackawanna County.

Crews will replace the existing structurally deficient steel I-beam bridge with a concrete bulb T-beam bridge.

Starting Dec. 27, Locust Ridge Road will be closed and detoured between River Court Road in Monroe County and River Road in Lackawanna County. The posted detour will route traffic on PA 940, PA 115, and River Road. Motorists are advised to allow for extra time when traveling through the area.

The project is expected to be complete in September 2012. All schedules are weather dependent.

The Thornhurst Bridge was constructed in 1946 and is posted with a three-ton weight limit. The Bridge is 105 feet long and 26 feet wide. The new Bridge will be 103 long and 44 feet wide. Locust Ridge Road has an average daily traffic of 3,146 vehicles.