Hundreds of thousands of San Francisco Bay Area commuters got at least a temporary reprieve from a massive transit strike when Gov. Jerry Brown intervened in a labor contract dispute.

Sunday night’s eleventh hour order averted the walkout and left the morning commute to proceed normally, without the widespread travel congestion that a strike involving Bay Area Rapid Transit, the nation’s fifth-largest rail line, would have created.

In the order, Brown named a board of investigators for a seven-day inquiry into the contract dispute that had labor unions poised to walk off the job at midnight Sunday.

The order was issued under a law that allows the state to intervene if a strike will significantly disrupt public transportation services and endanger public health. It came after BART Board President Tom Radulovich sent a letter to the governor requesting his intervention and a cooling off period of 60 days, BART spokesman Rick Rice said in a statement.

“For the sake of the people of the Bay Area, I urge — in the strongest terms possible — the parties to meet quickly and as long as necessary to get this dispute resolved,” Brown said in the order.

The board will report its findings to the governor, who can then petition a court to call a 60-day cooling-off period, said Evan Westrup, a spokesman for Brown. The report will explain BART and the unions’ positions, but will not find fault or issue a recommendation.

Meanwhile, commuters who rely on BART breathed a sigh of relief. Matthew Purpura, 25, commutes from San Francisco to Oakland, where he works as a coffee roaster. He said he would have borrowed his friend’s car to get to work, but the commute would have been a “nightmare.”

Alexis Braren, 33, commutes on BART within San Francisco, and walked three miles to her workplace when BART workers went on strike in July. BART service was shut down for four days during that strike, leading to clogged roadways and long lines for buses and ferries. Unions later agreed to call off the strike and extend their contracts until Sunday while negotiations continued.

“It made my life easier, that’s for sure,” Braren said about BART trains running on Monday.

Union leaders issued a critical statement after Brown’s order, accusing BART management negotiators of stalling until only hours remained before the strike would have begun to provide counter proposals on core pay and benefits.

“Our hope is that the Governor’s Board of Investigation will reveal how little time BART management has spent at the bargaining table in the past 30 days, compared with how much time they’ve spent posturing to the media,” said SEIU 1021 President Roxanne Sanchez.

BART spokeswoman Alicia Trost said late Sunday that it is “extremely frustrating” that the unions were misrepresenting the improved proposals they’ve been getting, including wage increases, and the transit authority was hard at work all weekend despite allegations of absence.

“We made several proposals this weekend and they all went in one direction and that was up, up, up,” said Trost.