Bay Area voters next year will be asked to raise tolls by as much as $3 on all bay bridges, except for the Golden Gate, under a measure the state Legislature just approved.

And more hikes could follow, with no cap, based on a cost of living index.

Regional Measure 3 was put together by Bay Area lawmakers with the goal of helping to finance 30 transportation projects throughout the region. It was approved by both the state Senate and Assembly after weeks of behind-the-scenes wrangling over who would get what.

The measure will likely go before voters in the nine Bay Area counties either next June or November, where it will need a simple majority to pass.

“Our residents already spend an average of 82 hours stuck in traffic and our transit systems are struggling to keep overcrowded buses and trains moving,” state Assemblyman David Chiu, D-San Francisco, said.

The projects include everything from improved bridge approaches and increased ferry service across the bay to bringing BART to Silicon Valley. The wish list even includes money to start building an underground tunnel for Caltrans to come directly into downtown San Francisco.

One of the biggest recipients will be BART, which is on track for just over $1 billion.

Getting the package through the legislature, however took a lot of back-room dealing, including an extra $200 million apiece for both Alameda and Contra Costa counties, where most of the people who would pay the higher tolls, live.

State Sen. Steve Glazer, D-Orinda, would only vote for the deal if it included the creation of an “inspector general” to monitor BART spending.

Even with the sweeteners, there was opposition from Contra Costa County, with state Assembly members Jim Frazier, D-Brentwood, Tim Grayson, D-Concord, and Catharine Baker, R-San Ramon, all voting “no.”

Frazier, who chairs the Assembly Transportation Committee, said that while there was a need for transportation improvements, “adding another tax on commuters is not the answer.” He likened an $8 toll to “highway robbery.”

Once in place, Baker said the tolls could keep going up without additional voter approval.

“And that takes away all accountability on how these dollars are spent,” she said.

The measure’s author, state Sen. Jim Beall, D- San Jose, praised the outcome, saying the measure will give the Bay Area “the bold plan it needs for the future” and that with the “expansion of tech firms, such as Google and Apple” traffic will only get worse.

Which may explain why tech companies are big supporters of the measure.

San Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or email matierandross@sfchronicle.com. Twitter: @matierandross