Streetsblog readers have likely read about Senator Diane Feinstein and Congressman Mark DeSaulnier’s call for a new cross-Bay road bridge between San Francisco and Oakland, to improve traffic on the Bay Bridge and its approaches.

From Feinstein and DeSaulnier’s letter to Steve Heminger, Executive Director of the Metropolitan Transportation Commission:

A second crossing would alleviate this traffic through San Francisco and the East Bay, would better connect the entire Bay Area, and would provide significant benefits for toll payers.

We have communicated in the past about the need for another Bay crossing, but this has not led to any concrete action. We need to move this issue forward expeditiously, and we would very much like your assistance in doing so. Please let us know what steps the MTC can take to move forward a new Bay crossing for both transit and vehicles, and more importantly, what we can do to assist you in this endeavor.

Streetsblog has a few questions for Feinstein and DeSaulnier–once all those additional cars cross from Oakland to San Francisco, where are they supposed to go? San Francisco’s streets are already chock-a-block. Are we going to put back the Embarcadero Freeway and extend 101 down Octavia again, in addition to expanding and widening more freeways, so those cars can get around San Francisco once they’ve crossed? And what about all the high rise parking garages we’re going to need to store them?

State Senator Scott Wiener wasted no time putting out a release in response to Feinstein and DeSaulnier. From Wiener’s statement:

We have limited resources for transportation improvements, and we need to prioritize moving people via public transit, not one car at a time across a toll bridge. Whatever the merits are of another bridge across the Bay, it is simply not as important as building a second transbay rail crossing. 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. 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. To create a more sustainable transportation future for the Bay Area, we must prioritize a public transit future, not continue living in a car-centric past.

We already have the Bay Bridge, the San Mateo Bridge, and the Dumbarton Bridge joining the East Bay and the San Francisco Peninsula by car. We have only one rail crossing–the BART Transbay Tube. Wiener is absolutely right–we need a second set of tubes connecting San Francisco and Oakland. In addition, what about reviving the Dumbarton rail bridge, which could be used to extend Caltrain to the East Bay? Wouldn’t even that, for pennies on the dollar, be a better use of scarce transportation funds than another highway bridge? (For a look at some of the options, and some history on past crossing proposals, check out UC Berekeley’s “Third Crossing” website).

There’s little doubt that Feinstein’s political muscle helped save Caltrain electrification and that her support for a second crossing for Caltrain, high speed rail, and/or BART would be welcome. It’s somewhat encouraging that at least Feinstein and DeSaulnier are asking that transit be included in the new crossing. But it’s difficult to imagine what the Honorable Senior Senator and a Concord Congressman are thinking when they suggest building a new road bridge that would dramatically increase the number of automobiles in San Francisco.