Traffic Signals Frequently Asked Questions
- Are the traffic signal coordinated?
- How do timing plans work?
- Do side street greens or pedestrian indications come up immediately when a vehicle approaches the intersection or when a pedestrian pushes the button?
- How are pedestrian timings determined, and why doesn't the "Walk" indication always come on?
- Why don't the lights flash amber and red late at night when less traffic is on the road?
- What happens to the traffic when a fire truck goes through a signalized intersection?
1. Are the traffic signals coordinated?
Yes. Traffic signals within defined groups along major roads are coordinated using timing plans with common cycle lengths. Timing plans are designed to provide minimum delay and stop time within each group. This does not mean that drivers will attain a green at every intersection, but rather overall network delays/stops will be minimized.
2. How do timing plans work?
Timing plans work by instituting a common cycle length (the amount of time necessary to display all traffic signal indications at an intersection) at intersections within a group. These plans control the points in the cycle length when the signals will be red, amber or green. By controlling the points when main street and side street greens occur, coordinated movement through an area can be achieved.
3. Do side street greens or pedestrian indications come up when a vehicle approaches the intersection or when a pedestrian pushes the push button?
No. As mentioned above, timing plans control the points in a cycle length when traffic signals will indicate red, amber or green. This time period is called a "window". Vehicles or pedestrian input a call to the intersection controller via loop detectors or through pedestrian push buttons, indicating a particular movement needs to be serviced. If the calls are input prior to the window appearing in the cycle the call is services at the proper time. If the call is input after the starting point of the window, that particular movement must wait for the next window to occur before it will be serviced.
4. How are pedestrian timings determined, and why doesn't the "Walk" indication always come on?
The Ministry of Transportation - Ontario (MTO) has established criteria, which bases pedestrian crossing time on the actual crossing distance. The "Walk" time will allow people to cover half of the crossing distance, as this symbol means it is safe to start crossing the street. The flashing "Don't Walk" provides enough time for pedestrians who have started to cross the street to complete their crossing before opposing traffic is released. The "Don't Walk" time is the longer component of the pedestrian time as it provides the appropriate clearance time to pedestrians who have started a crossing.
It takes longer for a pedestrian to cross a street than it does for a vehicle. At most intersections, the green signal for side-street movements is activated by means of a vehicle detector loop, which provides only enough time for a vehicle to clear the intersection. When additional vehicles pass over the detector, additional green time is added to permit them to clear the intersection.
Pedestrian push buttons tell the controller a pedestrian needs to cross the street and a longer crossing time is given. The pedestrian push button is the only means of activating the Pedestrian Signal and obtaining the required amount of crossing time for pedestrians. The push button will not change the light immediately, but will give adequate time for a safe crossing.
5. Why don't the lights flash amber and red late at night when less traffic is on the road?
The City of Windsor does not use "night flash" operations as studies indicate the collision rate increases by as much as 300% when this type of operation is used.
6. What happens to the traffic signals when a fire truck goes through a signalized intersection?
Windsor's fire trucks are equipped with a device which "pre-empts" normal operation of the traffic signals. During a pre-emption, a green indication is given to the signal movement, which the emergency vehicle is utilizing. All intersections on fire routes are equipped with pre-emption equipment.
Traffic Operations Division
1269 Mercer Street
Hours of Operation: 8:00 a.m. - 4:30 p.m.
Phone: For general information, call 311. For detailed inquiries, call (519) 255-6293.