With the City of Toronto set to give priority signals to LRT vehicles at intersections along both Finch and Eglinton, will drivers be left in the dust as trains speed by? Will you be sitting at red lights for longer? Will you have to wait until trains go by before you can make a left turn?
With so many questions about the system and how it will work, CityNews went looking for answers. Let’s start with the basics:
What is the Traffic Signal Priority (TSP) system?
The TSP system aims to speed up transit vehicles that use a right-of-way by making it less likely they have to wait at a red light.
Narayan Donaldson is an integrated mobility consultant with Mobycon and works with cities, including Toronto, to help improve transportation networks.
“[The TSP system] can be a sliding scale,” Donaldson told 680 NewsRadio Toronto.
“You have very slight adjustments that doesn’t make that much difference, or you can have very drastic adjustments that almost guarantees a green light for the transit.”
Related: Eglinton Crosstown LRT opening: How are trip times along Line 5 so far?
The TSP system can include some or all of four main components:
- Green light extension
- Red light truncation
- Phase rotation
- Phase insertion
Green light extension can hold the light green so an approaching LRT vehicle has time to make it through the intersection and is the simplest change to implement.
Red light truncation can shorten a red light so that the LRT vehicle doesn’t have to wait as long, but it doesn’t work at intersections with timed pedestrian crosswalks unless design changes are implemented as well.
Phase rotation can change the order of the signals in real time, and phase insertion can add an additional phase – like a left turn signal – into the cycle in real time.
“Currently, green extension is by far the most common change because that’s what’s possible everywhere,” Donaldson said.
What changes are the City of Toronto considering?
The City of Toronto is planning to implement two of the four elements of TSP along both Finch and Eglinton avenues: green light extension and phase rotation.
City spokesperson Kate Lear said city staff has already worked out a plan for how green light extension can be added at intersections where LRT vehicles interact with traffic.
“The maximum amount of time that it is possible to extend the green light is 16 seconds for Line 5 – Eglinton LRT, and 30 seconds for Line 6 – Finch West LRT due to LRT frequencies,” Lear told 680 NewsRadio Toronto.
Lear also said the city plans to implement phase rotation, allowing LRTs to go before vehicles intending to make left turn.
Related: ‘Absurd’ that new Finch West LRT line goes slower than buses: Matlow
“The City of Toronto plans to work with the TTC to implement an unconditional priority of both the Finch West LRT and Eglinton LRT vehicles to move ahead of left-turning vehicles at intersections,” Lear said.
“This will supplement the existing transit signal priority provided as part of the construction of both lines where green lights are extended to give the LRTs additional time to clear the intersection and shortening red lights to minimize delays.”
However, the city has not indicated any plans to implement red light truncation as part of TSP changes.
Lear says both corridors along Finch and Eglinton are being modelled using real time data to develop adjustments to the signals, allowing for maximum benefit for transit users while minimizing the impact on vehicle traffic.
In January, city council voted to expedite the process for adding TSP at intersections along both the TTC’s Line 6 and the above-ground portion of Line 5, but no firm date for those changes to be implemented has been announced.
Will it make your drive worse?
Given what could be considered a balanced approach by the city, Donaldson says the impact on motorists in neighbourhoods with priority signals for LRT vehicles will likely be negligible.
“I think in most places, the driver would have no idea. They wouldn’t notice the difference,” Donaldson said.
He added that, to offset what might be a longer green light due to approaching LRTs, ‘green light compensation’ is used to minimize the impact on other traffic.
“If you do something that impacts a particular movement – like the cross street – once the streetcar or LRT is gone, you give them extra time to compensate for that,” Donaldson said.
Related: Calls grow from TTC riders to improve Line 6 Finch West LRT trip times
Phase rotation is likely to be the most noticeable change the city could implement.
“When we introduce phase rotation, [drivers] might notice that the traffic signals are less predictable. So, they might not be able to guess which direction is going to get a green next because it will change in real time,” Donaldson said.
But Donaldson said, ultimately, a faster transit system can improve traffic flow by taking more cars off the road.
“[The TSP system] intends to achieve quite a lot for transit because if you can reduce delay for transit at signals, of course, you can attract more riders,” Donaldson said.
“And that’s really what we need in the City of Toronto. We’ve got way too much traffic on the roads. We need to attract more people out of their cars to free up space on the roads especially on lines where we have just-built dedicated rights-of-way for streetcars and LRT.”
