Last year's Port Authority service cuts were damaging. This year's would be cataclysmic.

Transit riders would be hardest hit if, as authority CEO Steve Bland has projected, the agency cuts service by 35 percent, eliminating 46 routes, scaling back the rest, shutting off most routes at 10 p.m. and giving up weekend service on many others.

Port Authority employees would suffer, too, because the attempt to close a $64 million deficit in the next fiscal year could mean 500 to 600 layoffs.

But the impact would extend far beyond the authority's 2,500 employees and its 220,000 daily bus and light-rail riders. Fewer people using mass transit means more people riding in cars. Anyone who noticed the jump in traffic on Banksville Road, Route 28 or the Parkway East after last March's service cuts can anticipate longer morning and evening rush hours. And don't get us started on parking.

People who work in offices, hospitals, schools and factories will face changes in routines because, without nighttime bus service, some of the work of cleaning, restocking or prepping for each work day may have to be shifted to daylight hours or dropped.

Pittsburgh's reputation as a place where students have easy access to higher education throughout the city will suffer a blow, as will its ability to lure companies seeking new homes.

People in other businesses could lose their jobs if they no longer have affordable access to their workplaces -- demoralizing for the employees and a burden on social services.

The harm will be permanent, and the system likely would never recover from such a large-scale rollback. But it doesn't have to be this way.

Gov. Tom Corbett can help. State aid makes up more than half of the agency's funding, but it took a 19 percent cut -- $34 million -- in the last fiscal year alone. Mass transit is just one part of the state's three-legged transportation funding problem -- the others are roads and bridges -- yet it is the one most likely to suffer in regional tugs of war over money.

It's shortsighted to conclude that taxpayers outside the county don't have an interest in Allegheny County's transit system. First, it is not alone -- the state's cities and many of its towns have their own bus services. Second, large cities are economic engines and without modern, efficient transit, Pennsylvania cannot compete against other states for new businesses and the jobs they bring. Third, the Port Authority has done a lot to distance itself from its outdated reputation for bloat and waste, with leaner contracts, route changes, job cuts and wage freezes.

Gov. Corbett is expected to announce his intentions for funding transportation next month when he unveils his 2012-13 budget. The Port Authority's challenges -- and their potential threat for the Pittsburgh region -- deserve his careful attention.