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I guess what this shows is two things: 1. Scaring people into slowing down is a viable way to avoid accidents. 2. Perceived scariness of an intersection is no

I guess what this shows is two things: 1. Scaring people into slowing down is a viable way to avoid accidents. 2. Perceived scariness of an intersection is not indicative of how dangerous it actually is.

TheCapn 7y ago
RE: #2 Absolutely. Within Saskatchewan, east of Regina, we just completed three new bridges for suburban communities to access the main highway. In two of the three bridges were atypical designs using a Diverging Diamond at one point, and dual roundabouts at the other. When announced lots of people were fearful of the new designs and there was unsurprisingly a lot of outcry from ninnies who were afraid of the unknown. There's been a couple instances of people taking improper directions on the bridges but they're typically by elderly drivers who probably shouldn't have been behind the wheel in the first place. I personally have my own qualms with the design of one of the bridges but that's outside this discussion. I like the concept enough that I hope to see them use diverging diamond more and more roundabouts as people get used to the efficient flow.
- kerkeslager 7y ago
  Another example of this is the downtown area of a small PA town I stopped in recently. They had recently re-paved the entire center street with brick and stone. The sidewalks were wide and there were no curbs, only rubber-covered metal posts marking the boundary between car and pedestrian areas. As a driver, I found this design scary, because it was hard to visually see where I should be driving. But I noticed that the natural result of this was that I drove around 15mph despite signs coming into the town saying 25mph as the speed limit. Another cause of this is that the sound of bricks under your tires gives the impression that you're going faster than you actually are. It was scary, but it put my focus as a driver on not hitting pedestrians, poles, or other cars, rather than slavishly following lines and curbs. Not hitting pedestrians, poles, and other cars is the entire point of the lines and curbs, so it's a more direct way to solve the problem. I think the fear aspect comes from the fact that hitting a pedestrian seemed like a real possibility the entire time I was in the town. But that fear is rational: there is a real possibility of hitting a pedestrian, and a high-foot-traffic area shouldn't be designed to assuage that rational fear. Drivers should be afraid of hitting pedestrians. A placard commemorating the redesign in the town square said that since the redesign in 2017, car/pedestrian accidents dropped from 279 to 43. * I'm citing numbers and locations from memory here so take this all with a grain of salt. I only stopped in the town for lunch on a long drive, so I don't remember all the details. My memory for numbers is usually good, but is not infallible.
  - JdeBP 7y ago
    This is actually a fairly common redesign that one can find in several countries around the world over the past decade or so.
- throw0101a 7y ago
  > Within Saskatchewan, east of Regina ... Is it possible to get (Google?) Maps links for these?
  - TheCapn 7y ago
    Hi there, sorry about my delayed reply, I don't typically check comment replies on HackerNews. Doesn't look like Google's satellite has updated photos but here's some links: The Diverging Diamond: https://www.google.com/maps/@50.4476864,-104.4361408,553m/data=!3m1!1e3 https://www.google.com/maps/@50.4476864,-104.4361408,553m/da... The Double-Roundabout: https://www.google.com/maps/@50.4769267,-104.2845914,552m/data=!3m1!1e3 https://www.google.com/maps/@50.4769267,-104.2845914,552m/da... The standard design: https://www.google.com/maps/@50.4471693,-104.3603897,781m/data=!3m1!1e3 https://www.google.com/maps/@50.4471693,-104.3603897,781m/da... Webpage of the project with some more info: https://www.reginabypass.ca/project/map-facts/ https://www.reginabypass.ca/project/map-facts/ EDIT: If you drop yourself down into street view it looks like you can see how the designs are laid out. No satellite view yet though
NeedMoreTea 7y ago
Aren't those ideas the underlying premise of shared streets (woonerfs)? Basically remove as many signs, markings and kerbs as possible so there's no segregation, and usually break up vision lines. The driver uncertainty stops traffic being the dominant user. Result lower accidents, much lower speeds, and above all safer cyclists, pedestrians and any kids playing.
- jandrese 7y ago
  Also far lower throughput, leading to severe daily congestion.
  - NeedMoreTea 7y ago
    Which is presumably why they are never used for major through routes, so don't cause severe daily congestion. Though I would like to see far more streets, even some with appreciable traffic, converted to downrank cars.
Ohn0 7y ago
Now imagine when "a police officer was stationed at each mini roundabout"!
- kerkeslager 7y ago
  I think that enforcing traffic law is one of the best ways to use police to keep the public safe. However, I suspect that having 5 cops at one intersection is a mis-allocation of resources. It would make that intersection safer, but at a pretty high salary cost, and even if the salary was available, it's likely at least some of the cops would be more useful at other intersections.

TheCapn 7y ago

RE: #2 Absolutely. Within Saskatchewan, east of Regina, we just completed three new bridges for suburban communities to access the main highway. In two of the three bridges were atypical designs using a Diverging Diamond at one point, and dual roundabouts at the other. When announced lots of people were fearful of the new designs and there was unsurprisingly a lot of outcry from ninnies who were afraid of the unknown. There's been a couple instances of people taking improper directions on the bridges but they're typically by elderly drivers who probably shouldn't have been behind the wheel in the first place. I personally have my own qualms with the design of one of the bridges but that's outside this discussion. I like the concept enough that I hope to see them use diverging diamond more and more roundabouts as people get used to the efficient flow.

kerkeslager 7y ago
Another example of this is the downtown area of a small PA town I stopped in recently. They had recently re-paved the entire center street with brick and stone. The sidewalks were wide and there were no curbs, only rubber-covered metal posts marking the boundary between car and pedestrian areas. As a driver, I found this design scary, because it was hard to visually see where I should be driving. But I noticed that the natural result of this was that I drove around 15mph despite signs coming into the town saying 25mph as the speed limit. Another cause of this is that the sound of bricks under your tires gives the impression that you're going faster than you actually are. It was scary, but it put my focus as a driver on not hitting pedestrians, poles, or other cars, rather than slavishly following lines and curbs. Not hitting pedestrians, poles, and other cars is the entire point of the lines and curbs, so it's a more direct way to solve the problem. I think the fear aspect comes from the fact that hitting a pedestrian seemed like a real possibility the entire time I was in the town. But that fear is rational: there is a real possibility of hitting a pedestrian, and a high-foot-traffic area shouldn't be designed to assuage that rational fear. Drivers should be afraid of hitting pedestrians. A placard commemorating the redesign in the town square said that since the redesign in 2017, car/pedestrian accidents dropped from 279 to 43. * I'm citing numbers and locations from memory here so take this all with a grain of salt. I only stopped in the town for lunch on a long drive, so I don't remember all the details. My memory for numbers is usually good, but is not infallible.
- JdeBP 7y ago
  This is actually a fairly common redesign that one can find in several countries around the world over the past decade or so.
throw0101a 7y ago
> Within Saskatchewan, east of Regina ... Is it possible to get (Google?) Maps links for these?
- TheCapn 7y ago
  Hi there, sorry about my delayed reply, I don't typically check comment replies on HackerNews. Doesn't look like Google's satellite has updated photos but here's some links: The Diverging Diamond: https://www.google.com/maps/@50.4476864,-104.4361408,553m/data=!3m1!1e3 https://www.google.com/maps/@50.4476864,-104.4361408,553m/da... The Double-Roundabout: https://www.google.com/maps/@50.4769267,-104.2845914,552m/data=!3m1!1e3 https://www.google.com/maps/@50.4769267,-104.2845914,552m/da... The standard design: https://www.google.com/maps/@50.4471693,-104.3603897,781m/data=!3m1!1e3 https://www.google.com/maps/@50.4471693,-104.3603897,781m/da... Webpage of the project with some more info: https://www.reginabypass.ca/project/map-facts/ https://www.reginabypass.ca/project/map-facts/ EDIT: If you drop yourself down into street view it looks like you can see how the designs are laid out. No satellite view yet though

NeedMoreTea 7y ago

Aren't those ideas the underlying premise of shared streets (woonerfs)? Basically remove as many signs, markings and kerbs as possible so there's no segregation, and usually break up vision lines. The driver uncertainty stops traffic being the dominant user. Result lower accidents, much lower speeds, and above all safer cyclists, pedestrians and any kids playing.

jandrese 7y ago
Also far lower throughput, leading to severe daily congestion.
- NeedMoreTea 7y ago
  Which is presumably why they are never used for major through routes, so don't cause severe daily congestion. Though I would like to see far more streets, even some with appreciable traffic, converted to downrank cars.

Ohn0 7y ago

Now imagine when "a police officer was stationed at each mini roundabout"!

kerkeslager 7y ago
I think that enforcing traffic law is one of the best ways to use police to keep the public safe. However, I suspect that having 5 cops at one intersection is a mis-allocation of resources. It would make that intersection safer, but at a pretty high salary cost, and even if the salary was available, it's likely at least some of the cops would be more useful at other intersections.