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Traffic signal FAQ

  1. The green signal is too short at the intersection on my travel route. Can you change the traffic signal to have a longer green signal?
  2. What is the process to add a dual turning lane to a traffic signal?
  3. Why is the coordination of traffic signal timing along my route not working?
  4. Why is the traffic signal cycling unnecessarily?
  5. Why is the red traffic signal so long?

1. The green signal is too short at the intersection on my travel route. Can you change the traffic signal to have a longer green signal?

Changing the traffic signal to give additional green signal time is not always a viable solution due to:

  • This action will also increase the red signal time in the opposing direction.
  • This action can cause delays to pedestrians.
  • If the intersection is coordinated it is constrained by the coordination and cycle length.
  • Longer cycles can result in queues spilling out of turn bays.

Traffic signal timings are programmed taking all directions of travel into account. This involves balancing the amount of green time for each direction based on factors such as traffic volume and pedestrian crossing.

2. What is the process to add a dual turning lane to a traffic signal?

The addition of a dual turn lane is a very complex process and it is often not the best solution for an intersection:

  • Sometimes this is not possible - the turning path of the second lane would intersect with an opposing vehicle path.
  • With dual turning lanes the type of arrow must be changed to a protected only arrow for safety reasons. This change may result in fewer vehicles making the turn at an intersection.
  • Physical space may not be available for an additional turn lane.
  • Shared lanes usually reduce intersection efficiency.

3. Why is the coordination of traffic signal timing along my route not working?

The coordination of traffic signals in a neighbourhood may not work because:

  • Not all intersections are connected to the city’s wireless traffic network. Onsite traffic crews periodically re-sync the signal controller clocks to adjust the timing.
  • Variability in traffic and pedestrian volumes can impact the series of green lights.
  • Some compromise is required to coordinate both directions of traffic equally.

In order to receive the full benefits of a coordinated series of traffic signals, vehicles should travel at a constant speed based on the speed limits for the neighbourhood.

4. Why is the Traffic Signal cycling unnecessarily?

The traffic signal may appear to be cycling excessively if a pedestrian has pushed the cross button in error or a vehicle on the sidestreet that was turning right activated the sidestreet vehicle detection system, but then completed their turn before the traffic signal switched phases.

5. Why is the red traffic signal so long?

Sometimes it seems like the red traffic signal is extremely long. This may be due to:

  • The driver has stopped their vehicle outside vehicle detection area used by the traffic signal. The vehicle detection area is usually located just behind the crosswalk or indicated by a stop bar painted on the road surface.
  • If the signal is coordinated, the driver may not have arrived during his or her coordinated interval.
  • The driver may be waiting for a pedestrian phase to be completed.
  • The detection system used by the traffic signal may be damaged.

For the traffic signal to detect a vehicle it is necessary for the driver to stop their vehicle at the stop bar or just before the crosswalk. The vehicle must come to a complete stop.

Traffic signal light
To find out more about how to add any of the above features or make an adjustment to a traffic signal in your area, please call 311.