AlvinofDiaspar
Moderator
Conversely, cars used to be courteous and let pedestrians cross first instead of butting across the lines and rushing the moment the light changes to green. What's needed is not having right turn on green.
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Roads: Traffic Signals
- Thread starter reaperexpress
- Start date
Conversely, cars used to be courteous and let pedestrians cross first instead of butting across the lines and rushing the moment the light changes to green. What's needed is not having right turn on green.
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Zach6668
Active Member
Are there examples of widespread no right turn on green rules in any jurisdiction?
If it's right turn on red only, cars still have pedestrians crossing in front of them to deal with, and then they just end up blocking the crosswalk.
AlvinofDiaspar
Moderator
Personally I favour a dedicated green signal for right-turning (synchronized with a four-way pedestrian stop) for downtown area with significant amount of pedestrian traffic but that's just me.
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Zach6668
Active Member
Downtown streets typically don't have right turn lanes, so what do you do if you show up wanting to turn right but the light is green to go straight. You just stop and wait for the cycle? Blocking through traffic?
I'm not a traffic operations guy, but a whole other dedicated phase for turning would increase pedestrian (and driver) wait time too, I'd imagine.
AlvinofDiaspar
Moderator
Unless the street in question is not well used by pedestrians that's pretty much the default situation already anyways - and if you aren't dealing with massive amount of turning traffic, a brief turning light prior to the pedestrian phase could be sufficient.
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rbt
Senior Member
Nearly every developed jurisdiction requires a right-hand turning (or non-driver side turning) vehicle to yield to a pedestrian at an intersection with a marked pedestrian crossing when both are given a "go" signal. In fact, as a general rule turning traffic yields to through traffic (whether you're going left or right) and pedestrians in this case are through traffic.
I say nearly all because it's possible that's not the case somewhere though I've not seen it yet.
AlvinofDiaspar
Moderator
Indeed. In fact, the situation now is more often than not the reverse - that pedestrians are yielding to drivers where they shouldn't have been at the the turn of the signal to start off with - simply because not yielding (which is their right) is invitation to getting run over - which is partly the "might is right" attitude of some drivers.
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ottbike
Active Member
ottbike
Active Member
W. K. Lis
Superstar
There used to be a time that Toronto didn't have any traffic signaled intersections.
For example, Dundas & Roncesvalles:
For example, Dundas & Roncesvalles:
W. K. Lis
Superstar
EastYorkTTCFan
Senior Member
I don't think we are doing it wrong at all just differently. Plus it's easier to see when it's on the far side rather then beside you. What happens if a truck is in the right lane and acar is in the left how are they supposed see when the signal changes if it's covered by a truck?
11th
Senior Member
I think there will still be a far side signal, at the opposite corner. It just won't be mounted on a gantry.
EastYorkTTCFan
Senior Member
I don't think we will ever see near side signals here as it's not really the standard in North America. Unless it's necessary do to other circumstances.
reaperexpress
Senior Member
Another advantage of having signals on the near-side only is that it allows for more precise all-way-red calculations which provide less all-red time without compromising safety. That's because of the way near-side-only signals automatically enforce the correct stopping position.
Take for example King & Sumach, which has enormous all-red times due to its awkward configuration and our primitive Ontario clearance calculations. For example, I'll look at the clearance time between the east-west phase and the northbound only phase which usually follows it.
East-west movements (terminating) shown in red, northbound movements (starting) shown in green:
In Ontario, the all-red time is simply the longest time it takes any of the terminating movements to clear a conflicting starting movement (or become effectively parallel with it). In this example, the critical movement is the eastbound curb lane, which has 35 metres between the stop bar and the point where it's nearly parallel with the northbound left turn movement. As per the standard Ontario calculation for a 40km/h zone, the all-red for this particular phase transition is therefore 3.7 seconds.
But once the northbound phase starts, it's still a few seconds before those cars actually reach the intersection, because the stop bar is so far back. That means there's wasted time where people are kept waiting unnecessarily.
Northbound traffic covers 28.5 metres before it conflicts with east-west vehicle traffic traffic.* At the 40 km/h, that takes 2.6 seconds.** So if we can be sure cars are actually stopped behind the stopbar we can give northbound traffic a 2.6-second head start to account for this, which leaves an east-west all-red time of 1.1 seconds. That's less than half the all-red time which would be required if we didn't account for the start-up time of the following phase (and in fact, this movement has a 5-second all-red, because the signal doesn't actually know which phase will come up next and therefore we need to design for clearing the entire intersection, not just the following movement). Saving 2 or 3 seconds during the phase transition is a huge deal when you consider that the northbound green can be as short as 7 seconds.
But in Ontario, our far-side signals mean that we cannot use this reduction factor, because there is a very real possibility that someone stops too far forward and therefore takes less time than we calculated to reach the intersection after the start of green. If there were only near-side signals, that wouldn't an issue because if a car stops too far forward, the driver can't see the signals anyway.
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* Terminating pedestrian movements are not considered in all-red calculations because the countdown will have already reached zero before the start of yellow. But starting pedestrian pedestrian movements are considered, since the Walk starts at the same time as the Green. In this case, the northbound phase has no pedestrian movements associated with it (the north-south pedestrian crossing runs with the southbound phase).
**Obviously in practice it would take considerably longer than this for cars to reach that point due to reaction times, acceleration time and turning speeds, but we need to design for this situation because it's legally possible for someone to cross the stopbar at 40km/h the instant the light turns green and continue through the intersection at that speed.
Note that despite the above, I don't think we should switch to near-side signals - it's a matter of cost. It would take billions if not trillions of dollars to convert every traffic signal in North America to near-side-only, given the number of signals and the cost of pole and utility relocation.
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