replace stop signs with signals on major transit lines?

From Streetsblog's Aaron Blalick in San Francisco:

The latest of [San Francisco Municipal Transporation Authority]'’s efforts to speed up [major bus] lines to run into some neighborhood opposition involves its proposed replacement of stop signs with transit-priority traffic signals. Some Western Addition neighbors have protested a proposal to signalize five intersections on McAllister Street to speed up the 5-Fulton, one of the designated “Rapid” routes receiving upgrades under the Muni Forward program (also known as the Transit Effectiveness Project).

Initially, the complaints were driven by fears that signals would bring dangerous speeding to McAllister. Muni planners responded by holding more outreach meetings, and presented data showing that pedestrian injuries declined on similar streets after signals were added. They also say speeds won’t go up significantly, since signals will be synchronized for speeds below 20 mph.  [emphasis added]

Aaron emailed to ask my opinion, which is emphatically:  "Who could oppose something that's good for both pedestrian safety and transit speeds?"

Apparently, the remaining opposition is based on "feel":

Sean Kennedy, the SFMTA’s Muni Forward program manager, said the data seems to quelled some neighbors’ fears, but that the complaints have shifted. “What we hear is that there’s a lot of concern over the neighborhood feel,” he said. “And that’s something we can’t really dispute with facts. It’s an individual preference if people do or don’t like signals.”

So how much should we worsen transit, and maintain higher levels of pedestrian injury, for the sake of "feel"?

And how exactly does a signal change feel?  We're talking about small streets here, mostly striped with a single wide travel lane each way.  Will a signal make the street feel wider?  Are people associating signals with more traffic and just assuming signals will have that outcome?  Not if they're timed for transit rather than cars.  Well-timed signalization can be very effective at discouraging car traffic on transit-intensive streets, when that's the objective.

I spent a decade of my life as a San Francisco pedestrian, in dark ages when pedestrian safetly mattered a lot less than it does now.  Sure, it was nice to encounter a 4-way stop where stepping into the intersection was enough to stop traffic.  

But among global pedestrians like me, San Francisco is famous for very fast signal cycles, and it's not a place where you'll be ticketed for crossing on red if there's obviously nothing coming.  As a pedestrian, I find a few seconds of delay a small price to pay for a transit system that's actually respectful of its customers' valuable time, not to mention the high cost to the public of its drivers' time.  

Remember: If you want frequency, you want less delay, because that makes frequency cheaper!

14 Responses to replace stop signs with signals on major transit lines?

  1. Morgan Wick November 10, 2014 at 2:19 pm #

    It sounds like the neighbors associate signals with major arterials and fear that a signal will make the street look more like one. Solution: ban car traffic from going more than a block or two on the street.

  2. anonymouse November 10, 2014 at 3:10 pm #

    The fact that a packed 2-car Muni train has to stop at stop signs makes a travesty of any claims SF may make of being a “transit-first” city.
    And besides, this the California, home of the “California stop” (i.e. not a stop at all), so it’s not like anyone actually stops at those stop signs.

  3. SFviews November 10, 2014 at 6:15 pm #

    Pedestrian injuries don’t “feel” very good. Those people who are against all change “just because” should be ashamed of themselves.

  4. asdf November 10, 2014 at 11:30 pm #

    On the contrary, when buses are asked to wait for a long red light at an intersection with minimal traffic, I wonder why they can’t just replace the signal with a stop sign.
    Also, stop signs tend to be much more friendly to pedestrians than signals because, with stop signs, you almost never have to wait to cross the street. Only when crossing an excessively-wide street with several lanes of traffic does a signal become preferable.

  5. Bradley November 11, 2014 at 2:58 am #

    Is there not a way to have a flashing red traffic signal (effectively an all-way stop sign) that can be preempted to a solid green (and a solid red for cross-traffic) when transit vehicles approach?

  6. Andre Lot November 11, 2014 at 6:50 am #

    They don’t need to time lights for traffic, they need smart traffic lights that recognize buses (or light rail if that was the case), and then adjust accordingly. This is the solution extensively used in places with heavy and dense transit surface traffic like Amsterdam or Zürich.

  7. patrick_sf November 11, 2014 at 5:14 pm #

    I live in the neighborhood and I oppose the signals on McAllister for these reasons:
    1) The 18 second delay number is made up. MTA breaks down the delay per stop sign thus:
    10 seconds for deceleration / acceleration. that is plausible
    5 seconds for queued cars. I guess that’s average, but is it average for those specific stops or the entire network’s stop signs? I rarely see long queues of cars at stop signs on McAllister.
    3 seconds for waiting at the stop sign. That is ridiculous! No bus stops for more than a fraction of a second. Most don’t even come to complete stops, and the ones don’t stop also will reduce the 10 seconds as they don’t do a full deceleration or acceleration.
    2) The signal prioritization only take affect if the bus arrives near the end of the light signal, not every time it approaches a signal. So the added signals will add longer delays when they are not able to catch the green
    3) It will slow cyclists and McAallister is a popular cyclist route.
    4) The pedestrian safety improvements can be accomplished without signals. Install bulb outs and the pedestrian safety is significantly improved, and can also make boarding faster for buses if the bulbouts are made big enough.
    None of these have anything to do with “feel”.

  8. Brent November 11, 2014 at 6:15 pm #

    10 seconds for acceleration and deceleration actually sounds a little long to me. Remember that it shouldn’t be the total time spent accelerating and decelerating — it’s the difference between that time and the time that it would otherwise take to travel that same distance. Assuming linear acceleration and deceleration, the net increase in travel time would be about half the total accel/decel time.

  9. david vartanoff November 11, 2014 at 7:16 pm #

    There is another reason to do this. SF Muni as well as AC Transit have drunk the kool aid of “all transit stops should be farside”. This means a bus/streetcar would stop at the 4-way, then cross and then make the revenue stop. Thus a traffic signal with transit priority becomes more important to moving riders. I should note that Rescue Muni gave SFMTA a route specific set of lists of 4 way stops and other “transit last” situations needing attention over a decade ago. Muni seems to have slept through the “great recession” before moving on these issues. They also never turned on the older transit priority software on the Embarcadero south segment of the K, N and baseball shuttle routes. One hopes that if the new TSP hardware is bought w/Fed money that they can be forced to actually use it.

  10. Gerald Fittipaldi November 11, 2014 at 9:52 pm #

    OK, I’ve got a bone to pick regarding pedestrian safety at intersections having stop signs vs. traffic signals. Jeff Speck has repeatedly shown, based on hardcore research, that stop signs are much safer for pedestrians than traffic signals. If this article is claiming that the opposite is true, let’s see the data. Perhaps it is case specific, but the vibe this article is giving is that traffic signals are generally safer. On this I disagree.
    “Author Jeff Speck cites a study of Philadelphia streets where traffic lights were removed in place of stop signs, and the result was a two-thirds reduction in pedestrian injuries (Persaud et. al.: “Crash Reductions related to Traffic Signal Removal in Philadelphia” (1997))” http://bit.ly/1sAlFtp

  11. valar84 November 11, 2014 at 9:57 pm #

    Strange, in Philadelphia, replacing traffic lights with 4-way stops reduced accidents significantly, with pedestrian injuries falling by 42%.
    http://www.interfaithenergy.com/rss/131-stoplight-removal-in-philadelphia
    As a pedestrian, I tend to like 4-way stop signs because they give me priority, I have no delay at all when crossing. Traffic lights are annoying as they force me to wait and leave only a small window to cross. I walk fast, so I’m fine, but many others aren’t like me. And intersections with beg buttons are particularly annoying, as I read somewhere else, beg buttons on traffic lights are like hitting the red light at every single traffic light.
    What this showcases is the big weakness of mixed-traffic transit: in order to provide fast service, they require streets that are by nature anti-urban, wide and fast, with control modes to maintain speed. On narrow, traffic-calmed urban streets, mixed-traffic transit is very slow, to the point that walking is actually faster for destinations under one mile, and for longer trips, bikes are significantly faster. In most urban areas, bike paths are probably a better investment than bus lanes.

  12. Marc November 12, 2014 at 6:59 am #

    “What this showcases is the big weakness of mixed-traffic transit: in order to provide fast service, they require
    streets that are by nature anti-urban, wide and fast, with control modes to maintain speed.”
    That does indeed seem to be the tendency and the downward trade. Unfortunately we live in a society that, for
    various reasons, has made the construction of grade-separated rapid transit corridors (tunnels, viaducts, or even arterials with light rail medians) insanely expensive, so we’re stuck in a predicament in which we have to struggle to balance the needs of pedestrians and mixed-traffic transit.
    I too prefer stop signs for the same reasons you noted – stop signs don’t really delay my walk, whereas traffic lights tend to stop me at every block.
    Philly is actually a rare exception – save for the wide Broad and Market axes, Center City mostly has one-way streets with traffic lights. But they work well for me as a pedestrian because:
    (1) They’re quite narrow (only one or two lanes wide, and that’s including parking!) which makes them quick and easy to cross.
    (2) You only have to look for traffic in one direction.
    (3) Most importantly – and unlike San Francisco, but very much like Portland! – their traffic lights are *timed for very short cycles* which means that I can either (1) walk quite a few blocks at a moderate pace before hitting a red light – the pedestrian equivalent of adjusting your speed to hit all the green lights – or (2) jaywalk in most red light instances, because they create many no-traffic pulses. And since the one-way streets are so narrow, that makes the jaywalking all the easier.
    This setup is helpful for buses too because (1) the short cycles seem to accomodate buses just like they do pedestrians and (2) where there aren’t official bulb-outs, in many instances buses are already stopping in the travel lane – thus avoiding delays from having to merge back into traffic – because there isn’t room to pull out of it on those narrow streets.
    For all this, though, the buses still limp along at an average 10-11mph … http://www.dvrpc.org/reports/08066.pdf … which beats Chicago and NYC, but lags behind Portland or suburban arterial-oriented agencies like NJ Transit. This isn’t due to the timing or one-waying, though, but to the many other delays associated with still-stuck-in-1950 bus operations (stops every block, onboard fare collection with single-door boarding, etc.)
    The report suggests improvements more or less in line with those cited here before … http://www.humantransit.org/2014/04/how-to-make-buses-more-useful.html … and while few of these improvements would make mixed-traffic transit on par with, say, a subway system, they could definitely boost reliability without turning streets into pedestrian obstacles.
    I would posit that extremely short signal cycles (like 30-60 seconds) can help both buses and pedestrians, but if the cycles are longer than that, then stop signs are preferable. So I’m actually surprised SF is proposing signalizing, because in my experience buses take advantage of stop signs just like pedestrians do – i.e. I’ve been on buses in Germantown and around Temple University that experienced far less delay going through stop signs after their revenue stops than being forced to wait at lights after said stops.

  13. Hanbzu November 12, 2014 at 2:09 pm #

    As Gerald points out, there is some research that says traffic signals don’t improve pedestrian safety—they may be worsening it.
    These studies are not only covered by people like Jeff Speck—who is an expert on walkability—but are greatly explained by Ben Hamilton-Baillie. It may sound counter productive, but green traffic lights disable an important mechanism in out mind that controls the hazards around us. If you remove the lights, you increase perceived risk and thus you improve safety.
    I understand that there is also a conflict between good transit and pedestrians. The lights would be useful for allowing faster speeds on the buses, and may be needed, but justifying them in the name of pedestrian safety may not be appropriate at all.

  14. EngineerScotty November 12, 2014 at 4:22 pm #

    Perhaps in many corridors, “green” lights should be abolished and replaced with flashing yellow?
    Or would doing so dilute the difference between the two, if motorists think they are equivalent?

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