SAN FRANCISCO (KCBS) – Members of 13 unions representing 450 workers at the Golden Gate Bridge, along with ferry and bus operators, are holding votes this week on whether to authorize a strike.

The unions and the Golden Gate Bridge, Highway and Transportation District have hit an impasse in contract talks. International Federation of Professional and Technical Engineers Local 21 representative Alex Tonisson said employees have been working without a contract since July 1.

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“We’ve been in negotiations since April,” he said. “Currently, our data shows that our wages are 12 percent behind the cost of living over the past decade.”

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Tonisson said there is also a dispute on health care for employees.

“The district is also proposing to dramatically increase the cost of health care,” he said.

If the 13 unions vote to authorize a strike, it could happen at any time. But the district is hoping an agreement can be reached before it gets to that point.

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“We met with them on Monday of this week and we’re scheduled to meet with them again Monday of next week,” said Golden Gate Bridge District General Manager Denis Mulligan. “I’m optimistic that we’ll reach an amicable settlement.”