By Daniel Kelley
PHILADELPHIA (Reuters) - The Philadelphia region is bracing for a potentially crippling transit strike that could compound the region's already significant traffic woes.
Unions representing about 400 engineers and electricians who operate trains that connect the city with its suburbs said they could walk off the job as early as Saturday when a mandatory 30-day cooling off period expires.
While a strike by these unions would not affect the city's subways or buses, it could put thousands of cars on the road as residents of small towns throughout the region are left with little choice but to drive to work.
SEPTA, the transit authority, says about 126,000 people use the 13 regional rail lines, which stretch from the city's northern suburbs to Wilmington, Delaware.
The unions have gone without a contract since 2009, but the issue came to a head this week after SEPTA management said it would impose a new contract on the workers. While the authority plans to raise wages, unions have balked at the plan because it was not negotiated and does not include retroactive pay increases for the years since the last contract expired.
Unions said in a statement issued Tuesday that imposing terms was likely to provoke a strike.
The region is already suffering through major jams on Interstate-95 after I-495, which bypasses Wilmington, Delaware, was closed because support columns on a bridge had tilted.
Officials have been urging commuters to take the regional rail line to Wilmington to help alleviate traffic in the area. The Delaware Department of Transportation announced a plan Tuesday that could see the interstate reopened in early September.
A strike on SEPTA's regional rail lines in 1983 lasted for 108 days.
The strike could be averted if Governor Tom Corbett asks President Barack Obama to impose a Presidential Emergency Board, which would delay a strike for 240 days while issues are mediated.
Jay Pagni, a spokesman for Corbett, said no decision has been made on whether the governor would make the request.
(Reporting by Daniel Kelley; Editing by Scott Malone and Eric Beech)