By Jonathan Kaminsky
(Reuters) - Bus drivers who threatened to strike a key San Francisco-area transit system earlier this month have voted to reject a tentative contract deal and to send labor negotiators back to the bargaining table, their union said on Sunday.
The tentative accord had been reached on August 6, averting a walkout planned for the next day by 1,800 drivers and other workers against the Alameda-Contra Costa Transit Agency, which serves Oakland and Berkeley and links those areas with downtown San Francisco.
But rank-and-file members of the Amalgamated Transit Union Local 192 voted overwhelmingly on Saturday, 576-257, against ratification of the settlement, the union said in a statement.
"Our members spoke out, loud and clear," said Yvonne Williams, union local president and business agent.
Union spokeswoman Sharon Cornu declined to comment beyond the union's written release, which said that its negotiators would "meet soon to review next steps."
Rejection of the contract proposal raises the possibility of further labor strife, but the statement made no explicit mention of whether the union intended to renew its strike threat.
Management declined to comment on the vote.
AC Transit is California's third-largest public bus system, serving 181,000 riders daily in two large counties - Alameda and Contra Costa, on the eastern side of San Francisco Bay.
The deal rebuffed by the rank-and-file called for a 9.5 percent wage hike over three years and annual flat-rate healthcare contributions by workers starting at $70, both sides have said.
Union workers initially demanded wage hikes totaling about 10 percent over three years, while the transit board sought to hold wage increases to 9 percent, company officials said.
The setback in labor talks comes after California Governor Jerry Brown intervened to block the resumption of a separate strike against commuter rail service threatened by unions representing workers at the Bay Area Rapid Transit, or BART, system.
Union members began negotiations with the AC Transit board in March, four months before the contract expired.
(Reporting by Jonathan Kaminsky; Editing by Steve Gorman and Will Dunham)