Tuesday, August 11, 2009

Central Subway Perspective

Ah, the Central Subway.

What more can be said about the Central Subway? Conceived in some form at least 80 years ago, and put into motion by a vote of the people 20 years ago, the project seems like a done deal despite protests from some transit activists and NIMBYs alike.

One major concern is that the CS as currently planned is less than optimally designed, and way too expensive. Opponents point to the price tag of $1.58 billion for 1.7 miles of rail as ridiculously prohibitive.

Without disagreeing on those points, I'd like us all to pause, stand back and get a little perspective. Transbay Blog, in an unrelated post about the new bike lane on the Benicia-Martinez bridge, reminds us of the cost of that span: "$1.26 billion for 1.2 miles" of highway over the Carquinez Strait.

That fact elicits a number of reactions from me:
  • Why must a transit project in downtown SF scrape for funding comparable to that which is thrown to readily at highway projects in BFE?
  • Why are transit advocates spending time and energy on infighting?
  • Where was the outrage at the cost of the B-M span?
I suspect everyone reading this has their own answers to those questions. Please feel free to discuss them in the comments, or add your own reactions.


Jamison said...

I'm one of those opposed to the Central Subway, but since it's going to happen there are some decisions made to cut back on the upfront construction costs that will drive up operational costs and limit it's usefulness in the future.

The stations have already been downsized from three-car to two-car with the assumption we'll never need 3-car trains.

Moscone Station's single entrance is located a block away at Fourth & Folsom (on the gas station lot) for a few reasons. First, locating it any closer would require moving a major sewer line or cutting into/redesigning part of the Moscone complex below ground. Secondly, demand during conventions would be more than a single entrance could accommodate so moving it further away will reduce number of riders using it. So third, capacity is already limited by the single entrance which might keep it from ever needing 3-car service.

Union Square Station will be connected to Powell Station via a walkway beginning where the concourse currently ends at the Apple Store. Even with escalators the walk will be several blocks and require leaving and re-entering the fare gates. BART is in between so a platform-to-platform connection is out of the question, but Powell Station could already use some work (it leaks, it could be more visually distinct from Montgomery) and there are ways that transfer could be made easier. Perhaps a down escalator from the eastern faregates to the platform, or if you take the elevator down you can see there's at least a hundred feet of unfinished platform and I wonder what if it would be possible to relocate the entire boarding area east to be closer to Union Square Station.

We also need to start talking about extensions. Those giant tunnel boring machines will be laying tunnels all the way to Washington Square, were they will be dug out of the ground, and there will never be a better opportunity to build a station in North Beach. We already have to dig a giant whole in the ground down to pair of subway tunnels, is there any good reason to fill it in with dirt and concrete instead of just building a station?

Pedestrianist said...

Dang, Jamison, you wrote more in your comment than I did in my post! :-)

I agree with all of your points. The decision to go below the BART tunnel has led to some pretty stubborn design flaws (including the southern location of Moscone station, which allows the tunnel to start descending earlier). One thing on which savemuni.com and I agree completely is that there seems to be enough room to do a shallow subway and avoid all these problems.

But I actually find that most of savemuni.com's arguments contradict each other. Por ejemplo, the CS will reduce transit service, but it will also not save money because they won't be cutting the bus lines. Transit service won't be reduced if the existing lines aren't cut (a good thing, IMHO) but yes, it will cost more.

As for extensions, I know you've read my thoughts on connecting the CS with the H-Potrero Van Ness :-)

An extension of some sort seems to be the modification to the CS as planned that is most likely to actually happen.

My concerns are the ones you articulated. Muni is spending more on this than they have to, and it could be designed better.

But my point about perspective stands: more per mile spent for a bridge in the boonies and nobody raises an eyebrow.

Clearly, this kind of money is a reasonable amount to spend on a transportation project as long as it involves asphalt.

Jarrett at HumanTransit.org said...

Re the small platforms Jamison mentions, note that this subway is mostly for VERY short trips, which means it requires VERY high frequency, and at such a high frequency you probably don't need such a large trainset.

Connectivity to Powell is a big deal, of course, as is extendability to the north. But even if it goes all the way to the Marina someday it will still be about rather short trips, which means high frequency, which means you may get away with shorter trains.

Not an expert in the details of this project, just noting the relationship between the variables.

Pedestrianist said...

Very good point, Jarrett.

One complicating factor for short, high-frequency trains is the CS' integration with the T-Third light rail line.

Not insurmountable, but it's not like building a subway across Market Street under downtown SF wasn't hard enough! :-/

Jamison said...

I think we share the same perspective that the standards for funding bridge and transit projects are absurdly disproportionate.

On deep or shallow tunnels, the original idea was to cross Market Street at Third Street which is a little deep than Fourth Street where the plan ended up (there are sketches in the EIR). That should be considered when comparing the plans, some good comes of the Fourth Street route because moving the (portal where it goes into a tunnel) under the bridge allowed for an additional surface station at the very busy Fourth & Brannan intersection.

What seems like contraction is probably confusion because there isn't really a concrete "plan" for what will happen with bus service once the central subway opens. Some kind of reduction in bus service will happen when the Central Subway opens and what's most likely to go so the 30-Stockton short line. The highest capacity busses on the 30-line are the long articulated 60' busses, which turn around at Van Ness instead of going all the way out to the Marina. A one-car train carries more people than even the largest bus, so shutting down the 30-short line wouldn't reduce frequency for the majority of people riding it and still adding more combined capacity from Chinatown on south.

The busses will be fewer and less-frequent, but it going down to the subway will feel slower because you know a bus is still going to come sooner than the time it would take you to walk down to the subway and wait for the next train. For most people it means things just got worse, not better.

At start up the only Central Subway line will be the T-Third Street which runs most of it's in a dedicated right-of-way on the surface and reliability will depend on how well it all those surface crossings trough some of SOMA's most highly trafficked intersections.

It will take more than that to hit the tipping point and become a better value for both operations and for riders. That means extensions and/or expanding to multiple branching lines like we have today coming out of West Portal with the KLM going their separate ways. Complicating things would be bad for reliability and could end up with the problems the Market Street subway has right now. Since the first phase is a certainty, I think the sooner talks start happening about an extension the more opportunity there will be for public scrutiny and good ideas to surface.