OAKLAND — Over the past decade or more, the Bay Area’s boundaries have been bleeding into surrounding counties as skyrocketing housing prices push residents farther from jobs centered in Silicon Valley and San Francisco.

Those residents are still employed in the Bay Area though, leading to longer commutes and mounting pressure on the region’s roads and rails. While that trend has been ongoing for some time, the problems resulting from it have become particularly acute, according to a new report released Thursday by the Bay Area Council, a business-sponsored public policy advocate.

“All these people are moving around on the most congested corridors,” said Jeff Bellisario, the research manager for the Bay Area Council Economic Institute, “and there’s no great transit options for these commuters.”

Approximately 602,000 vehicles enter and exit the nine-county Bay Area from other parts of what the council has dubbed the “Northern California Megaregion,” an area comprising six counties in and around Sacramento, three Northern San Joaquin Valley area counties, and three Monterey Bay area counties.

The Northern San Joaquin Valley area is leading the region in the number of workers it is sending to Bay Area companies. Between 1990 and 2013, the number of people commuting from the valley to job centers in the Bay Area more than doubled, growing around 32,000 commuters to nearly 65,000, according to the report.

“Silicon Valley really likes our labor force, but our labor force really doesn’t like the Silicon Valley’s housing costs,” said Mike Ammann, president and CEO of San Joaquin Partnership, a nonprofit economic development corporation.

San Joaquin Valley was also one of the hardest hit in the housing market crash that spurred the Great Recession, but Ammann said the double-digit unemployment numbers in the area have since come down. Manufacturing has picked up, as has the county’s distribution and transportation industries, and more housing is being built in the region again, he said.

However, this uneven growth in jobs and housing has caused gridlock on Interstate 580, and while the Altamont Corridor Express train, or ACE, is not yet at capacity, it soon will be, said Dan Leavitt, the transit agency’s manager of regional initiatives.

The agency’s ridership has roughly doubled in the past five years, and ACE is looking for ways to expand, Levitt said. It’s currently in the process of drafting an environmental impact report, set to be released in the fall, that would study an increase in the number of round trips from four to six, and within the next decade, Leavitt said the agency hopes to offer 10 round trips.

To do that, the passenger service needs to add a second set of railroad tracks in some places, as well as make other improvements, Leavitt said, a roughly $200 million investment for the first phase and another $200 million for the second. ACE already has funding for the planning and preconstruction phase of the project, but not the actual construction, he said.

“In order for us to (expand service), we would need more infrastructure along our lines, but also other things like equipment and more parking,” Leavitt said. “First and foremost, the biggest hurdle is funding.”

While the state has some cap-and-trade funds available for commuter rail projects, Leavitt said the project will require investment from counties along the rail line serves.

Encouraging local governments to think regionally has never been easy, said Randy Rentschler, the legislation and public affairs director of the Metropolitan Transportation Commission, but encouraging municipal and county governments to do so has never been more critical, he said.

He pointed to the express lane on Interstate 580, which opened earlier this year, as an example of regional collaboration that provided some relief to drivers stuck in gridlock.

“The planning and the fight … to get that money on those lanes; we had to take on most of the rest of the state to make sure that these congested areas were prioritized,” Rentschler said. “We succeeded in part because we worked closely with our friends in the San Joaquin Valley area.”

As people continue to move further from job centers in search of cheaper housing, Rentschler said the problems will only get worse.

“Being the repository for your neighbor’s housing stock can only go so far,” he said.

The report recommends, among other things, investing in regional rail lines, streamlining permitting for housing construction so it can be built closer to job centers, and encouraging job growth in the San Joaquin Valley and Sacramento areas to help relieve the daily migration to the Bay Area. Coupled with that is a long-term strategy to invest in education in places like Sacramento and Merced, so that companies can more readily access a high-skilled labor pool, Bellisario said.

“Part of the conversation is about transportation, part is about the economy, but really, they both go together,” Bellisario said. “We need to spread the economic footprint more evenly across the entire megaregion.”

Contact Erin Baldassari at 510-208-6428. Follow her at Twitter.com/e_baldi.