SAN FRANCISCO (CBS SF) – Federal lawmakers are pushing the Metropolitan Transportation Commission to build a new bridge across the San Francisco Bay, but state Sen.  Scott Wiener, D-San Francisco, says that funding could be better used to build another cross-bay BART tunnel.

U.S. Sen. Dianne Feinstein, D-California, and Rep. Mark DeSaulnier, D-Concord, sent a letter Wednesday urging the MTC to construct an additional east-to-west bridge south of the Bay Bridge to ease commuting traffic, which has increased by 80 percent since 2010.

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“The traffic demands on our streets and transit systems have become intolerable,” the letter said. “Quality of life is suffering; and, our economy is not nearly thriving as much as it could be if these transportation challenges were addressed.”

Senate Bill 595, which was passed by the Legislature and signed by Gov. Jerry Brown, and Regional Measure 3, which is set to go before voters in 2018, are expected to generate funding that could be used to ease traffic in the Bay Area, according to DeSaulnier and Feinstein.

But Wiener wants to see that money allocated to public transit, rather than moving “one car at a time across a toll bridge.”

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“Whatever the merits are of another bridge across the Bay, it is simply not as important as building a second transbay rail crossing,” Wiener said in a statement this morning.

“A second tube can mean more BART trains running, including 24 hour service, a connection between Caltrain and the Capitol Corridor, and high speed rail to the East Bay,” Wiener said. “That is how we are going to reduce gridlock, not by building another bridge that pours more cars onto our highways on both sides of the Bay.”

There are currently four east-to-west bridges crossing the Bay, including the Richmond-San Rafael Bridge that connects the San Rafael area to Richmond along Interstate Highway 580, the Bay Bridge that connects San Francisco to Oakland along Interstate Highway 80, the San Mateo-Hayward Bridge that connects Foster City to Hayward along state Highway 92, and the Dumbarton Bridge that connects Menlo Park to Fremont along state Highway 84.

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