PennDOT is building a temporary bridge along I-83 in Cumberland County. (Submitted photo)

Traffic on Interstate 83 in Cumberland County will be detoured off the highway Saturday as a temporary bridge is put in place.

The temporary bridge will carry traffic on Lowther Street in Lemoyne over I-83 as the existing bridge is demolished and replaced with a permanent four-lane bridge, said Mike Crochunis, a state Department of Transportation spokesman.

The steel-constructed temporary bridge will be opened to traffic Aug. 18 until the end of May, when the new bridge is scheduled to be completed.

Crews will move the mostly pre-constructed temporary bridge into place and then will have to pave the road deck, Crochunis said.

"It's more like an Erector set going over 83," he said.

Detours: Apart from the detour on Saturday, I-83 will have to be closed four additional times as the project progresses.

Detours will be set up when the existing bridge is demolished, twice to install new bridge beams, and finally to remove the temporary structure. PennDOT will issue travel advisories when this work is scheduled.

All told, the project is projected to cost nearly $8 million. Susquehanna Valley Construction Corporation of New Cumberland will perform the work.

The bridge replacement project will pave the way for additional construction to widen I-83 and to alter ramps in the area.

"It'll follow on the heels of this project," Crochunis said.

The overall project should decrease traffic congestion.

The existing single-span concrete bridge was built in 1952 and is considered functionally obsolete. It is a major contributing factor to the bottleneck on I-83 northbound. I-83 cannot be widened until it is removed, Crochunis said.

Detour details: Here are detours that will be set up on Interstate 83 as part of the bridge project in Lemoyne:

* I-83 North will be directed off at Brandt Avenue, turn right onto Lowther Street through Lemoyne back to I-83 North.

* I-83 North traffic headed to Route 581 West will also follow Brandt Avenue to Lowther Street and continue on I-83 North across the Susquehanna River into Harrisburg and be directed off at Exit 44-A for 13th Street to I-83 South back across the Susquehanna River to Route 581 West.

* I-83 South will be directed off at Exit 42 for Lemoyne, follow Lowther Street, turn left at 10th Street and back to I-83 South.

* Route 581 East traffic headed to I-83 South will be directed to I-83 North to Exit 41-B for Highland Park, turn right onto Lowther Street and turn left at 10th Street to I-83 South.

- Reach Greg Gross at ggross@yorkdispatch.com.