Bay Area Rapid Transit's two largest unions this week ratified the new labor agreements that ended a four-day regional rail strike in October.

In a statement posted on BART's website Saturday, officials said the new four-year agreements would address the growing cost of employee benefits while allowing the agency to modernize an aging infrastructure.

“The Bay Area and our riders will benefit from these contracts because BART will be able to move forward with the replacement of our aging fleet of train cars and the needed upgrades to meet demand,” BART General Manager Grace Crunican said in a statement.

PHOTOS: BART commuters deal with second strike

The stop-and-start negotiations between management and its two biggest unions -- Service Employees International Union Local 1021 and Amalgamated Transit Union Local 1555 -- lurched toward a four-day strike in October, sending thousands of Bay Area commuters scrambling to find alternative methods of transportation.

It was the second strike to hamper travel and commerce in the region since July, when a 4 1/2-day walkout was brought to a close by the intervention of Gov. Jerry Brown, who later called for a 60-day cooling-off period.

Under the new labor agreements, union members will start paying into their pensions. Changes were also made to healthcare coverage and retirement benefits. In exchange, workers will get a roughly 15.3% pay raise over the next four years.

BART also agreed to make a number of workplace safety improvements, such as shatterproof protective film at station booths, and to discuss other upgrades.

SEIU workers voted overwhelmingly Friday to accept the new contract, with 88% in favor, according to the union.

“BART workers — just like other workers — want to be safe when they go to work," said John Arantes, an SEIU chapter president. "Today our members resoundingly approved an agreement that would increase awareness of the dangerous working conditions facing many workers and a way to immediately address those concerns.”

Amalgamated Transit Union Local 1555 members voted 85% in favor of the contract.

BART board members must still vote on the labor deals at a future meeting.

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jason.wells@latimes.com

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