PRT is preparing the century-old Panhandle Bridge — which carries light rail over the Monongahela River between Station Square and First Avenue — for what the agency called a “major” long-term rehabilitation project worth $58 million.

The initial preparation work, which will not affect light rail service, involves painting, electrical work and concrete substructure repairs, PRT spokesman Adam Brandolph said.

The project will begin next spring and take 32 months to complete. Pittsburgh-based Mosites Construction Co. will repair steel and concrete, install lighting “for both service and decorative purposes” and replace rail and power lines, Brandolph said.

“The rehabilitation and restoration project is intended to extend the bridge’s useful life and help ensure that PRT can continue providing safe, reliable light rail service to Downtown for future generations,” Brandolph said.

Light rail service will drop from two tracks to one between the South Hills Junction and First Avenue Station during construction, and commuters should expect weekend bridge closures that affect both buses and light rail, Brandolph said.

PRT plans to announce specific closures and detours when the construction schedule is final.

The Panhandle Bridge opened in 1903 and originally served the Pittsburgh and Steubenville Railroad Company’s route through the northern panhandle of West Virginia. PRT converted the bridge to serve light rail in 1984.

Those interested can read more about the project on PRT’s website.