San Francisco Explores Removing 280 Freeway Viaduct, Realigning HSR
San Francisco Mayor Ed Lee and his administration have been working on a proposal that would reshape transportation routes in Mission Bay. The concept would be to take down the Interstate 280 viaduct past Mariposa Street by Potrero Hill to its current end by the Caltrain station at 4th and King. This would enable the HSR tracks and potentially the 4th and King station itself to be moved from its current location to another place nearby. And that in turn could change the route used for the downtown extension tunnel that would connect the existing tracks to the Transbay Terminal.
Green Caltrain has a good overview of the proposal:
San Francisco would love to bring Bus Rapid Transit down 16th street to Mission Bay, connecting to BART and other Muni lines. But the 16th street at-grade crossing is nearing gridlock today; more trains from electrified Caltrain and high speed rail will make grade separation a necessity. With the freeway in place and the tracks above ground, the road would need to go under the tracks, creating an environment even more hostile to walking and biking, and even larger concrete barriers separating neighborhoods even further.
“So,”, said Gillett, “let’s be San Francisco and take down the freeway.” The crowd in the packed room gasped and laughed. With the successful transformation of the Embarcadero and the Central Freeway to Octavia Boulevard, the bold plan might just work.
Removing the freeway past Mariposa might enable more options to iron out the expensive, train-slowing stair-step alignment of the Downtown Extension of the Caltrain tracks to Transbay terminal. The picture below shows alternative alignments brainstormed at a 2011 design charette convened by the San Francisco County Transportation Authority. The quickly sketched alignment proposals also have problems, but perhaps further study would find feasible alternatives that at least partly smooth out the kinks in the curve.
Green Caltrain has much more details on the plans, including power point presentations put together by SFCTA describing the concept.
One potential challenge is how this would align with Caltrain’s electrification plans, but the agency seems open to the idea:
In order to achieve this vision, San Francisco is asking Caltrain to swap rail storage at 4th and King for other locations on side tracks within existing rights of way. This request was described in a memo to MTC Executive Director Steve Heminger in a response to a request for San Francisco’s policy position on the Caltrain electrification environmental review process.
San Francisco is asking Caltrain to electrify less of the railyards at 4th and King to enable the City to make progress on its land use plans. The benefit to Caltrain would include increased ridership from a station area even richer with jobs and residences, as well as an “opportunity to create real estate value which can be used to fund transit and Caltrain investments.”…
Seamus Murphy, Caltrain’s director of government and community affairs, said that Caltrain would like to work with San Francisco on a solution that enabled the city to use land productively, as long they can find viable places to store the trains, and don’t have a major impact on Caltrain’s electrification schedule.
Overall the concept strikes me as a sound one. It could also help address a concern raised repeatedly by rail advocates that the curves of the existing DTX tunnel proposal are too tight. The SFCTA plan would allow a straighter tunnel to be bored from Mission Bay to the Transbay Terminal, although potential issues do exist with pilings for some of the buildings in Mission Bay. That in turn could help ease operations in the DTX and improve train speeds coming out of the Transbay Terminal.
Obviously many details remain to be sorted out. But San Francisco appears willing to do the work to see if this is a viable concept. If the details can be worked out, this proposal looks like it will provide better passenger rail service for Caltrain and high speed rail, as well as helping San Francisco continue to add more density, something it surely needs.