SAN FRANCISCO (KCBS) – Bay Area Rapid Transit is looking to ask for another $1.5 billion as part of a bridge toll increase that could go on Bay Area ballots as early as 2018.

KCBS and Chronicle Insider Phil Matier reports in Wednesday morning’s Matier and Ross Column that the idea pushed by BART and other transit agencies is to raise tolls on the Bay Area’s seven state-owned toll bridges by $1 to $3. The Golden Gate Bridge would not be part of the toll increase.

Officials are still haggling over the exact amount, but the upper range would boost the top cost of crossing the Bay in a car to $9.

BART says what it needs most is 306 additional railcars. There is no money in Measure RR, a $3.5 billion maintenance bond passed by voters last year, to pay for them.

New train cars will cost a lot of cash, $1.6 billion, to be exact.

The transit agency hopes $1 billion of that will come from the envisioned toll-increase measure, which would still leave it $600 million short of what it needs for all the cars.