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Blackstone Boulevard Plan Requires Reform on Butler

I've been meeting with decision-makers about the Blackstone Boulevard proposal put forward by Hugo Bruggeman. The pushback I've gotten has been that in the morning and evening rush hours, there is a backup of vehicles on the southern end of Blackstone Boulevard near its connection to Butler.

To reemphasize, the interesting part of the Blackstone Boulevard slow zone proposal is that it does not remove any capacity for cars. It takes a two-lane road and moves the order of lanes around, so that north- and south-bound traffic face each other on the same side of the street. The other side of the boulevard becomes a 15 mph "slow zone" or woonerf, not unlike what already exists on Commonwealth Avenue in Newton, Mass. In a sense, the slow zone proposal adds car capacity, since now drivers would be allowed everywhere. It just gives priority to cyclists and pedestrians on one side of the street by slowing traffic and preventing through-traffic on that side. Nonetheless, some people view this proposal as somehow harmful to drivers, and claims about congestion are key to this argument.

I've encountered Blackstone as a zone for speeding far more than congestion, and I think a degree of backup on streets is a normal part of living in a city, but nonetheless I think that congestion can be addressed on Blackstone Boulevard. It just takes looking at what causes it.

Butler, which is essentially an extension of Blackstone Boulevard, is a two-lane road for its entire length, except at its intersections with Waterman and Angell Streets, each of which gets a turning lane. Both of these intersections get traffic lights. These are the only traffic lights joined by one other traffic light at Pitman Street on the Butler/Blackstone length. This is where the congestion happens.

The way to fix congestion at these intersections is to make them blinking red lights, and to take away the turning lane. A turning lane typically doubles the capacity of the street to take vehicles, but also allows those vehicles to act in less safe ways towards pedestrians. These two intersections of Butler with Angell and Waterman are some of the ugliest places to cross a street as a pedestrian on the East Side. Removing the signals, or making them blinking red lights will restore capacity for vehicles by allowing drivers to stop, look around them, and continue, rather than being stacked at a traffic light.

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)). The logic behind this change is clear if one thinks about it. Cyclists know it firsthand: a fast-moving car can pass at two to three times the speed of a bike and be caught at the same light as the cyclist. This can sometimes happen several times. The speed of the vehicles between lights matters much less than the wait time they have at lights. A kind of tortoise and the hare, writ large.


I haven't yet been able to get ahold of the Philadelphia study to read it myself, but this is consistent with what Speck talks about in his study of large, Midwestern "stroads" he's redesigned. In those cases, he's often taken four lane or wider roads and reduced them to two lanes, added traffic calming, and removed signals. The travel times have greatly improved for drivers, while the walking experience has improved for everyone else. Slow and steady wins the race.


The Butler project really matters because I'm told by a source within City Council that the city is already looking at retiming the signals here to improve traffic flow. These changes could affect the way the street works for pedestrians, making it even worse than it is, and may not necessarily help drivers in the way is intended. Instead of retiming signals, the city would do better to experiment with turning the signals to blinking red, obstructing the turning lanes, and allowing drivers to flow through the intersection. This will reduce crashes, and help drive times.

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5 comments:

  1. Good point. I'll note that if it doesn't work well, they could always go back to retiming the lights with little cost.
    Also, it helps reduce the speeding up dangerously to make a green light.
    Barry Schiller

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  2. Interesting, I'd go further and say that in addition to removing the turn lane, eliminate the parking on Angell between the Henderson Bridge and Butler, and install a lane that logically connects to Butler (giving a legal right to access the northbound boulevard). More/different traffic calming needs to exist east of the traffic light on butler, to get people down from the 45mph bridge speeds to the 25mph street speeds we desire, which is I think part of the function of that light.

    In other contexts, there has been discussion to closing River Rd to through traffic, and most of the opposition to this idea has come from people who identify River Rd as the way to circumvent the Angell/Waterman/Pitman congestion and traffic lights.

    I'd be seriously worried what retiming those lights will mean. My fear would be it makes a green wave from the Henderson to Thayer, allowing for some serious speeding to take place.

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  3. I don't know.

    I think removing parking to put a bus lane or a bike lane, or to extend a sidewalk, is always fine, but to speed up cars getting through from the Henderson Bridge sounds like a bad idea. But maybe I don't follow what you mean.

    I think maybe dealing with signals might have to happen in a systematic way. Like, once you deal with this axis, you have to deal with the ones on Angell and Waterman, and so on. I think ultimately it leads to all the two-lane streets in the neighborhood going without signals. Probably the only places that should have signals at all are roads with more than two lanes, like Memorial, N. Main, etc.

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  4. I see my comment was poorly worded. I was trying to say use the current parking lane/turn lane on Angell for a bike lane to ease the connection onto Butler. I was also trying to say that traffic calming on Henderson and on the uphill on Angell east of Butler before the light really should be considered, as traffic on the Henderson really does achieve highway speeds, making it really unsafe at the interfaces/ends of existing Henderson bike lanes.

    After further thought, A 4 way stop on Angell at Butler would likely not work well. Butler/Waterman and Butler/Pitman would probably work better since there are no incoming 2-lane streets to those intersections. I've yet to notice a street with 2 same direction lanes with a stop sign work properly where traffic volumes are significant. The "take turns approach" breaks down if you can't see to your left across the car next to you, cars arrive at different cycles in each lane.

    If Angell could be cut to one lane entering the intersection, or a 2-way street from Butler eastwards down, that would be better, but that would require a pretty significant change to the Henderson Expressway interchange.

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  5. I think I agree with you about two-lane, one-way roads with stop signs, although I would tend to hope that Angell and Waterman get protected bike lanes to bring the two-lane part of the road to one. There's really no need for that much capacity on Angell and Waterman, especially since any through traffic has to come down to one lane around Brown anyway.

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