Improvements in Median Transit Design

[reaperexpress]

Not right. St. Clair DOES have priority and it is switched on. Just shows that signal priority does not specifically mean "guaranteed green light".

In fact, ALL streetcar routes have some form of signal priority. (Believe it or not!) The system on St, Clair is more intelligent that that on other lines.

Check out this (old-ish) presentation on TTC signal priority:
http://www.signalsystems.org.vt.edu/documents/July2004AnnualMeeting/attach/m8_Sinikas.pdf

That's the exact same presentation that I cited in my post. It refers to a trial of 6 traffic lights, and suggests that it would be a good idea to implement system-wide transit priority. It does not prove that said transit-priority was actually implemented.

EDIT: Maybe you're referring to the map near the end. That is showing where transit priority is "equipped", not where it's activated. We already knew it's equipped on St. Clair and Spadina.

 

[CDL.TO]

That's the exact same presentation that I cited in my post. It refers to a trial of 6 traffic lights, and suggests that it would be a good idea to implement system-wide transit priority. It does not prove that said transit-priority was actually implemented.

EDIT: Maybe you're referring to the map near the end. That is showing where transit priority is "equipped", not where it's activated. We already knew it's equipped on St. Clair and Spadina.

Ha ha ha. So it is. The 6-intersection refers to the 1990 trial. The same presentation says that 155 intersections are equipped on streetcar routes and 115 intersections on bus routes, and that was in 2004. You can see it in action all over the city today. The only place I've heard about it being installed but not activated is on Spadina.

I'm not referring to the map at the end. I'm saying that signal priority is installed and is active on St. Clair. Not on Spadina.

When a streetcar passes through an intersection, the system knows how long it should take the streetcar to reach the next intersection and times the signal so that the streetcar is more likely to get a green. Obviously, there are limitations to this. If it's going to take 20 seconds for a streetcar to reach the next intersection, and with the cross street having to cycle through the pedestrian crossing, yellow, and red means that a green can't be given to a streetcar for 35 seconds, then that's that and the streetcar isn't going to get a green.

 

[reaperexpress]

Ha ha ha. So it is. The 6-intersection refers to the 1990 trial. The same presentation says that 155 intersections are equipped on streetcar routes and 115 intersections on bus routes, and that was in 2004. You can see it in action all over the city today. The only place I've heard about it being installed but not activated is on Spadina.

I'm not referring to the map at the end. I'm saying that signal priority is installed and is active on St. Clair. Not on Spadina.

Oh cool, do you have any sources? I'd like to read up on what they're using.

 

[CDL.TO]

Oh cool, do you have any sources? I'd like to read up on what they're using.

Sorry, my source was a tour of the streetcar system with the TTC's lead engineer on the signal priority file.

I seem to recall that Steve Munro has said this as well. He probably has some stuff on signal priority on his blog.

 

[reaperexpress]

Sorry, my source was a tour of the streetcar system with the TTC's lead engineer on the signal priority file.

I seem to recall that Steve Munro has said this as well. He probably has some stuff on signal priority on his blog.

Yeah, I just went and looked there. You are right, they do have transit priority on St. Clair. Apparantly they initially had issues with not holding green lights quite long enough, but once they fixed that, the biggest issue seems to be left turns.

 

[CDL.TO]

It would be nice if they put a short-as-feasible transit phase before the left turn phase on Spadina and St Clair. It shouldn't take more than 5-10 seconds. Maybe if the roads department denies it at the major intersection, why not at the minor ones?

 

[lafard]

In some cases, "transit priority" doesn't mean much.

I've seen the "transit priority" at say College and Beverly in action. Basically, it holds the light green until hypothetically the streetcar is done loading and can pass through. (you can tell this is activated because the ped signal counts down to 0 and goes steady hand but the traffic light doesn't turn)

The delayed signal doesn't wait forever, though, and if there are a lot of people to board (say, because the streetcars are bunched, as if that ever happens) then they seem to just miss the light and have to wait an entire signal cycle.

There are "white bars" at various places especially harbourfront, but I've also seen it at St Clair and Vaughan. This is only really useful for taking vehicles out of service though.

 

[GraphicMatt]

Are there transit priority systems out there that, instead of using a loop in the ground, work via operator request? ie. a streetcar/bus driver hits a button on board their vehicle to request a green at an intersection?

This would eliminate the common situation where the light is held green but the streetcar can't take advantage of it because it's still boarding.

 

[W. K. Lis]

The roads department is more concerned about vehicles not passengers. For them, a vehicle carrying only one occupant is the same as a vehicle carrying 5, 10, 40, or 100 occupants. That is why vehicles turning left are given priority over streetcars at traffic signals, especially if there are more than one vehicle. A streetcar carrying 100 passengers will have to wait to allow the three cars carrying only the driver in each to complete their left turns. There are attempts to change that thinking, but it will take time to change the mindset.

 

[DSC]

Are there transit priority systems out there that, instead of using a loop in the ground, work via operator request? ie. a streetcar/bus driver hits a button on board their vehicle to request a green at an intersection?

This would eliminate the common situation where the light is held green but the streetcar can't take advantage of it because it's still boarding.

This is a very good quesion and one I too have wondered about. From my observations on King Street it is a frequent occurence to see a streetcar having a green light but neither it nor other traffic can proceed because it is still boarding.

 

[CDL.TO]

This is a very good quesion and one I too have wondered about. From my observations on King Street it is a frequent occurence to see a streetcar having a green light but neither it nor other traffic can proceed because it is still boarding.

It just reinforces that the real debate isn't yes transit priority vs no transit priority, but instead the design of any potential transit priority system.

 

[doady]

In some cases, "transit priority" doesn't mean much.

I've seen the "transit priority" at say College and Beverly in action. Basically, it holds the light green until hypothetically the streetcar is done loading and can pass through. (you can tell this is activated because the ped signal counts down to 0 and goes steady hand but the traffic light doesn't turn)

The delayed signal doesn't wait forever, though, and if there are a lot of people to board (say, because the streetcars are bunched, as if that ever happens) then they seem to just miss the light and have to wait an entire signal cycle.

And that's why the transit signal priority along Hurontario was deactivated. Signal priority works much better with far side stops (most bus stops along Hurontairo are on the near side). So if there are no far side stops, don't bother with signal priority. And if there is no signal priority, don't bother with median transit ROWs, as the Spadina streetcar shows...

 

[Electrify]

This would never work in Toronto. Too many selfish drivers that would simply block up the ROW while waiting to make their left turn in this configuration. The best approach is a simple one: When a bus approaches an intersection, right before the left turn signal, let the bus through via a short maybe 5 second green light for the bus. Then continue on with left turn cycle and general green. The city is too afraid to experiment with such things because engineers say it will delay left turning cars. In fact, it is the cars that are delaying the buses.

We could use protected crossings to keep drivers from going on to the tracks as a train approaches. They could even be fitted with cameras to enforce fines (something we should do with all our streetcar doors as well BTW).

That video is different from an earlier one, where traffic in all directions shuts down to make room for the bus:

http://www.vivanext.com/vivaLaunch (1:15, 1:28 and 1:50)

 

[Woodbridge_Heights]

Of course some drivers will start crossing the ROW before there is space in the turn lane for their car, and be forced to sit in the ROW blocking oncoming trains. This applies for people not paying attention, people who don't know how to drive properly, and jerks.

Retractable bollards could be used to prevent this.

These are normally always up, a vehicle sensor embedded in the road on each side detects a car and ensures that there is no car on the other side and that there are no LRT vehicles incoming. Bollards retract and vehicle crosses to the other side of the tracks. This would be metered for only one vehicle at a time. This is similar to what's in use on the QEW in Mississauga where the on ramps are signalized with traffic lights that are metered to one vehicle per green.

Should some bozo try to rush the bollards... SOL

** I just saw that Electrify posted a similar solution to mine***

 

[jwill]

Retractable bollards, sensors, etc. all cost a lot of money. Is it worth it to solve a problem that wouldn't exist if we just re-arranged the light phases at intersections?

It sounds like an overly complex solution, with potential for frozen bollards, lags in maintenance, cars running over half-retracted bollards, etc.