Friday, September 26, 2014

The Streetcar Fiasco

Streetcars have become a major fad over the past few years, ever since Portland put in theirs.
Portland Streetcar
In Portland's case, the streetcar is a pretty decent investment: it acts as a circulator overlay on a high-quality light rail system. But after they put theirs in a bunch of other cities began to construct streetcars for themselves.
H Street Line, Washington, DC
DC's H Street line was the second major streetcar; it is also the first that suggested an underlying problem. You see, H Street is supposed to be a spine corridor, linking the city's east side with its west. It thus needs to be built to a higher standard capacity than ... that.
This particular design -- at the time, novel* -- contains two catastrophic mistakes that permanently mar this line's capacity:
  1. The line has been built in a mixed traffic lane rather than be given its own dedicated lane. This reduces the streetcar's speed and makes it no better than a bigger bus on rails. Part of what makes light rail successful** is the dedicated lane. Without this lane the line is unable to bypass car congestion and thus provide the positive time differential that helped justify e.g. Salt Lake's investment.
  2. The line has been built in the outer lane. This second point makes it own strange kind of sense -- once you've decided not to build a dedicated ROW, there's something vaguely suicidal about asking passengers to run across a traffic lane unless you're willing to put carstops in, and if you're doing curb bumpouts as well, then why not put those there? However -- by putting the streetcar track in the outer lane you create conflicts between the streetcar and parallel parkers, delaying the transit vehicle for a single driver. These kinds of conflicts slow down vehicles on our country's remaining historic streetcar lines all the time -- one of the reasons Boston's Green Line is one of the most reliable is because (unlike the examples in Philly, Toronto, and San Francisco) the vast majority of the surface system lies in dedicated medians.
H Street was a difficult design challenge. The street is, surprisingly, 90 feet wide, and it is fairly congested -- its AADT hovers a little above the max capacity of a two-lane street -- and a full light-rail buildout would have likely required (among other things) taking of a parking lane significant street reconfiguration, much like 1st Street in San José, a bright spot in the VTA system.
1st Street, San José
Indeed, it is arguable that the H Street Line's optimal placement would have been for the light rail to lie between the sidewalk and the parking lanes, with a road diet reducing auto capacity just enough to convince (some) drivers to Take Other Routes. This arrangement, however, remains problematic in its own right, and is not the thrust of this post -- and I have talked about these kinds of things before.
Woodward Avenue, ca. 1942. Note that even then there was little real congestion.
M-1 Streetcar plan reveals same engineering failures as H Street -- this time, with even less excuse.
At least two Midwestern cities have taken the (failed) H Street approach and applied it to themselves: Detroit and Kansas City. I haven't been to Detroit, but I will note that Woodward Avenue, which is eye-poppingly wide relative to traffic, can easily accommodate every single mode, if the designers chose to.
Kansas City Streetcar render
What is perhaps most shameful is that within these ... things ... lies the fact that the powers-that-be continue to refuse to give up any street space for cars, no matter how ridiculous the car gluttony may be *cough cough Detroit, Kansas City cough cough*, and are packaging it as a political sop to Millennials.

No. The transportation investment that would please us the most is in quality bike infrastructure. We want to ride around everywhere. Bike-friendly cities are Millennials' cities.
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* Portland's downtown streets are only 40 feet wide; historic streetcars ran in the middle of the street. (See, for example, Philly's trolleys.)
** And good BRT -- Cleveland's Euclid Avenue being the only such example in the United States today.

3 comments:

  1. This is off topic, but I liked your thoughts on SEPTA in Pennsylvania. (I grew up near Media.) You said then that you were going to write some thoughts about commuter trains on the New Jersey side, and I wondered if you’d ever gotten around to doing that...

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  2. Really appreciated this much-needed critique of streetcar enthusiasm. My concern with their popularity likewise boils down to their frequent lack of a dedicated lane: are we engaging in fatal procrastination by not insisting upfront on the same lane dedication for transit that we already insist on for automobile traffic?

    That is, while it's possible a mixed-traffic streetcar might eventually generate a vocal-enough constituency to demand a dedicated lane, this is still a very rare occurrence in the US. Even if the constituency is already there, it's silent because it's tired, working hard, and distracted with other things - while the competing drivers are not. So I think establishing a DOT culture in which dedicated transit lanes are demanded upfront is crucial, but current streetcar practice only keeps pushing this back.

    As you noted, surface rail needs a dedicated lane to be time-competitive with the automobile, but if we keep on deferring the debate over this fundamental need (because the solution WILL require the reallocation of automobile lanes, in many cases along streets that have ample space for other modes, as in all the examples in the post), all we do is saddle cities with mediocre transit and give ammunition to *true* transit opponents: "See, all rail is useless and slow! Let's not build any more of it!"

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  3. My overall interpretation of the mixed-traffic streetcar fervor is that it seems to rest on three shaky conclusions:

    (1) "Streetcars worked well in our urban past, so they'll work well in the urban present." While this sentiment is understandable, it neglects the context in which the streetcars of yore were successful. As that photo of Woodward Avenue reveals, few prewar streets suffered from automobile congestion.

    But this is no longer the case: streetcars are no longer being overlaid onto empty, overwide streets, they are being overlaid onto streets that are either clogged with cars or clogged with concessions for cars even if the cars themselves are absent (in the cases of Detroit and KC).

    The contemporary street context is thus very different from the prewar street context and requires a different approach: now that we have automobile congestion, we have to give surface transit its own lanes just as we do for cars. It's no accident that most of the surviving prewar streetcar systems, like Philly's Subway-Surface lines, survived because their congested downtown segments were tunneled (i.e. given a dedicated lane).

    (2) "Trams work well in European cities, and they could work well in US cities." Again, this assumption lacks an appreciation of context. Although there is much idle blurring of "tram" and "streetcar" in causal discussion, the two are actually very different. Although there certainly are mixed-traffic segments on European tram networks, for the most part the mode can be described as a network in which transit vehicles travel on narrow streets purged of cars in the historic city centers (usually pedestrian zones) and on dedicated medians along boulevards outside the centers.

    Again, this is nothing like mixed-traffic American streetcars: while American cities are feebly layering tracks onto overly-wide, autocentric streets to avoid upsetting drivers, European cities (the UK perhaps excepted) aggressively try to the do the opposite for their remaining mixed-traffic segments.

    (3) "Let's not make the perfect the enemy of the good." This assumes that mixed-traffic streetcars are "good." As one person pointed out below...
    http://www.citylab.com/commute/2014/10/hey-streetcar-critics-stop-making-perfect-the-enemy-of-good/380913/
    ... the bad and the mediocre are also enemies of the good. What if mixed-traffic streetcars are actually bad and mediocre? Dedicated transit lanes are not some wildly-unrealistic "perfect." They're a basic good, and given the ample space on wide American streets, not insisting on them is pretty bad.

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