A $19.6 million project to transform a century-old building at the gritty 69th Street terminal complex into a sleek, modern structure that will be greener and more passenger-friendly was officially begun Monday.

"This is going to be a model for how we will be able to make old buildings sustainable," said Rep. Patrick Meehan (R., Pa.), one of several politicians at Monday's groundbreaking ceremony. Actual construction work began last fall.

Meehan predicted that the upgrades to West Terminal would draw more passengers and bolster the local economy. West Terminal is one of three wings at the 69th Street Transportation Center in Upper Darby Township, which is used by 35,000 people daily.

The teardrop-shape structure will be redesigned to reduce energy costs and storm-water runoff.

The project will add better-lighted passageways, more seating, surveillance cameras, and improved access for passengers using wheelchairs.

But in the short term, the project will be disruptive for passengers on several routes that serve Philadelphia and Chester, Delaware, and Montgomery Counties.

Beginning June 15, the West Terminal will be closed to allow demolition work.

Shuttle buses will be used in place of trolley Routes 101 and 102, and the boarding locations for those buses will be moved to the South Terminal.

Bus Routes 104, 112, 120 and 126 will be relocated to a temporary boarding location near Market Street and Chatham Road. Routes 107, 109, 110 and 111 have been operating out of the temporary location since February.

And Route 123 will move permanently to the North Terminal.

West Terminal likely will reopen Sept. 8, officials said. The project will be completed by November.

The project, which SEPTA officials said has added from 50 to 60 temporary construction jobs, was funded by a Federal Transit Administration grant program and Pennsylvania Act 89, a transportation funding law passed in 2013.

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