New passenger buses ordered by SEPTA have been delayed by production problems, forcing the transit agency to continue operating old buses that are increasingly prone to mechanical breakdowns.

The first of 275 new electric-diesel buses purchased for $202.6 million was delivered this week, SEPTA officials said Wednesday.

The first bus is more than a year behind schedule. The vehicles are being built by Nova Bus, Inc., a subsidiary of Volvo Bus Corp., headquartered in Saint-Eustache, Quebec, Canada.

Much of the assembly of the SEPTA buses is being done at a Nova plant in Plattsburgh, N.Y.

The buses have been delayed by a shortage of workers, improper seat installation, faulty electrical systems, and bus panels that were painted the wrong color, SEPTA officials said.

Nova faces penalties of $100 per bus for each day it is late.

"The worst is behind us," Ronald Hopkins, assistant general manager of operations for SEPTA, said Wednesday. "We think all the big engineering problems are worked out."

Hopkins said the production delays created service problems for SEPTA, because of increasing maintenance difficulties with the existing fleet, some of which is 18 years old.

SEPTA has 1,400 buses, and it is seeking to replace about 100 buses a year to reduce the average age of a bus to six years.

Seventy new 60-foot-long "articulated" buses, with an accordion-style body section to permit tighter turning, are now expected to be delivered to SEPTA by the end of December, Hopkins said.

Ninety 40-foot-long buses are now scheduled to be delivered by January, 2015, Hopkins said.

An additional 45 60-foot buses are expected by May, 2015, and 40 more 60-footers are scheduled to arrive by August, 2015.

Those 85 buses are still on schedule, SEPTA spokesman Andrew Busch said.

In addition, SEPTA recently exercised its option to purchase 30 more 60-foot buses from Nova for $24.2 million.

Those buses are scheduled to be delivered by the first quarter of 2016, Hopkins said.

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