NEW CASTLE, Pa. - Drivers planning to travel on the Pennsylvania Turnpike should be aware of construction that will mean an hour-long detour.

Bridge replacement projects in Beaver and Lehigh Counties will close two sections of the turnpike for 55 hours this weekend and next weekend.

Both east and westbound turnpike lanes between New Castle and Cranberry will be closed from 9 p.m. Friday, Sept. 22, through 4 a.m. Monday, Sept. 25 in Beaver County.

The detour exits are the New Castle Interchange (#10) for eastbound travelers and the Cranberry Interchange (#28) for westbound travelers.

The authorized detour route will direct motorists to Interstate 376, Interstate 80 and Interstate 79.

During those same hours, a week later the Northeastern Extension (I-476, milepost 57.66) in Lehigh County will be closed from Friday night until Monday morning.

The detour exits are Lehigh Valley Interchange (#56) for northbound travelers and the Pocono Interchange (#95) for southbound travelers.

The authorized detour route will direct motorists to Route 22, Route 33 and Interstate 80.

Turnpike officials say the authorized detour routes will be clearly marked for both through traffic and local traffic. Drivers should look for for the orange and black directional signs.

The Pennsylvania Turnpike is using an engineering procedure, Accelerated Bridge Construction, that allows workers to replace bridges in 55 hours instead of requiring a year or more of construction that would impact traffic.

Officials say the technique improves safety for workers and drivers.