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This is part of a multi-part reflection I've been doing following the death of my friend, Mark Baumer . There's nothing graphic i...

Signaling Compromise

I've been thinking about signals a lot, both for some bike projects I'm looking at, as well as for the 6/10 Connector project.

I'll probably make other posts about "green wave" signaling, but this post is going to focus on designalizing intersections.

I wrote a bit about S. Water Street, and how the nominal bike path on the sidewalk doesn't work. The biggest issue (besides occasionally very high use by pedestrians) with having the "bike path" there is the fact that signaling on either end doesn't allow convenient crossing. For instance, crossing Point Street to where the East Bay Bike Path picks up is a nightmare because it requires waiting through two signal cycles to cross each way. This is the kind of detail that RIDOT gets wrong because it's not used to thinking of bikes as an important mode of transportation, and it's one of the reasons you rarely see anyone use the so-called "bike path" or the dangerous parking-adjacent bike lane on S. Water.


Being able to cross would be easier with a "pedestrian scramble". The other day when I was passing through this area, I got thinking about how that might mix with the idea of designalizing the intersections entirely. 

There's a real debate over how best to use (or not use) signals for traffic. Here's a video I've posted before, which I know has also been featured on Greater City Providence, about the city of Poynton in the UK.


Designaling intersections lowers people's peak speeds through those intersections, but because people can pause momentarily and move on, it also improves their overall travel times (think: "Slow and steady wins the race."). This has a big safety improvement effect for many users, in addition to being better for traffic.

There are a bunch of contrary facts to this theory, though.

The first is that although slower speeds are better than faster speeds for people on bikes and pedestrians, traffic volumes have a huge effect on the perception (and reality) of safety too. I know this from first-hand experience from having lived in Philadelphia. Many streets have four-way stops, and this does encourage more biking, and slower, more deliberate behavior from drivers. But if you're in a narrow lane biking in front of even the most conscientious driver, you still feel uncomfortable. So separated areas are good, especially for bicyclists. David Hembrow* made a good video talking about how to create separate crossings for bike paths that are away from traffic circles:

The other issue is that although some disabled people have testified their opinion that shared space and designalization works for them, many others are uncomfortable with it. There is a real movement among blind people in the UK to object to shared space proposals.


I've been thinking a lot about this issue. I have a proposal that I think takes the best from both worlds:

*Set up two-lane-meet-two-lane intersections so that they have a default setting of blinking red lights in both directions. This means that traffic would flow more smoothly, but at lower speeds, and for many users would provide more safety (objectively and subjectively). 

*Maintain the ped "beg buttons" but set them to allow for "pedestrian scrambles". A pedestrian scramble is when traffic stops in all four directions. By having the ped scramble be an option by request, people with special needs, like the blind, would be able to access an enhanced crossing.

A big downside to this proposal is that beg buttons and signals still cost a lot of money. One of the advantages of four-way stop signs is their markedly lower cost. In many cases, Dutch cities have reduced the amount of signals they use, but this has been by reducing traffic volumes along certain corridors. So we should consider all of these options.

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*David Hembrow HATES HATES HATES any kind of designalization or "shared space". So fair warning.


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