PITTSBURGH — Some southwestern Pennsylvania officials are broaching the idea of consolidating the region’s 10 transit agencies into one, arguing that such efforts could save taxpayers millions.

Allegheny County Executive Rich Fitzgerald told state lawmakers last week that 30 percent of downtown Pittsburgh workers live outside the county, while many county residents work and shop in Butler or Washington counties.

“It’s frustrating when you watch buses come across the (Allegheny) county line and they don’t pick up another person as they drive into Downtown using the same route as a Port Authority bus,” he said.

Gov. Tom Corbett’s budget proposal would provide an extra $1.8 billion a year for transportation statewide on the condition that transit agencies complete consolidation studies with neighboring agencies. Consolidation could involve combining entire agencies or just sharing purchasing or services.

The Pennsylvania Department of Transportation would decide which agencies should partner for studies and would pay for the work, slashing funding to agencies that don’t implement cost-saving recommendations in what department secretary Barry Schoch calls a “carrot and stick” approach.

Lackawanna and Luzerne counties in northeastern Pennsylvania say they expect to save $1.8 million a year by consolidating administration of their medical assistance and shared-ride services. An advisory commission appointed by the governor predicted that consolidations could cut transit costs statewide as much as $25 million per year.

A study last fall predicted that combining operations of five transit agencies and two county transportation departments in south-central Pennsylvania could net $24 million in savings in seven years. Former Allegheny County Controller Dan Onorato promoted consolidation during his first campaign for county executive in 2003, but didn’t advance the idea during his two terms in office.

Fitzgerald played off the acronym for the Philadelphia-area’s Southeastern Pennsylvania Transportation Authority in proposing a consolidation on the other end of the commonwealth.

“We need a ‘SWEPTA’ to reflect how people go to work and live,” Fitzgerald told lawmakers, referring to a hypothetical Southwestern Pennsylvania Transit Authority.