Traffic signals

Traffic signals are designed, installed, operated and maintained by the City of Ottawa ensuring the safe, efficient and sustainable movement of people and goods within the community through the use of:

• Technologically advanced software and hardware
• Signal timing, including special phasing for peak hours, weather conditions, special events and construction
• Progression and synchronization between signals
• A cohesive system which maximizes the capacity of existing infrastructure

The operation of traffic signals has a major impact on stops, delays and travel times for various users of the transportation system. The application of state-of-the-art technology and in-house software development has resulted in a customized, central, traffic-control system and traffic-control equipment tailored specifically to the City’s needs. This improves safety, efficiency and reliability at all signalized intersections located within the City of Ottawa.

Mitigating the effects of congestion and the increasing demands on the transportation system helps to reduce fuel consumption and the negative impacts to air quality. The traffic control system is continuously monitored, with real-time adjustments implemented in response to peak hour congestion, weather conditions, special events and construction. Signal timings are continuously monitored and updated to reflect changing traffic patterns and volumes.

Information related to traffic signal operation, coordination, pedestrian signals, vehicle detection and left turn signals is listed on the Traffic Signals page.

Traffic signals are timed to minimize stops and delay for all traffic using the intersection. Many factors contribute to the disruption of ideal progression, including varying speeds, the presence of left-turning signals, the distance between signals, varying amounts of green time required by traffic on cross streets and congestion from very high traffic volumes.

Perfect synchronization for one direction of traffic on a street results in frequent stops and delays to the other direction. A compromise that favours the heavier direction of flow is usually best.

In general, each intersection has at least seven basic timing plans designed to accommodate traffic patterns during the following periods:

• AM peak period
• PM peak period
• Off peak
• Evening
• Late Night
• Saturday and;
• Sunday

Many intersections have additional plans to accommodate special conditions that may result from heavy snowfalls, shopping activities, special events, or other known fluctuations in traffic flow.

Timing updates to major corridor are scheduled on an annual basis. Unscheduled changes are made annually in response to public inquiries, observed changes in traffic patterns resulting from development, road construction and changing travel patterns.

Evaluating the need for Left-turn arrows

There are normally factors that are considered when evaluating the need for a left-turn arrow signal, including:

1. Left turn accident history
2. How well is the left-turn movement operating without a turn signal
3. How much will the left-turn signal increase waiting times to the other traffic movements at the intersection

Left turn signal phases facilitate left turning traffic and usually improve the safety of the intersection for left turning vehicles. However, this is done at the expense of the amount of green time available for through traffic and will usually reduce the capacity of the intersection. Left turn arrows also result in longer cycle lengths, which will affect stopping and delays. Pedestrian delays may be increased due to the increased delay.

Types of Left Turn Phasing

Protected/Permitted Left Turn Phasing

A separate interval is provided to accommodate a left turn without conflicting traffic and left turns are permitted during the coinciding through movement.

Protected Only Left Turn Phasing

A separate interval is provided to accommodate a left turn without conflicting traffic and left turns are prohibited during the rest of the cycle.

Vehicle detectors are made of metal detecting wire imbedded in the pavement at the approach to the intersection and are used to activate and extend the green displays.

Approximately 70 per cent of the City’s traffic signals have pedestrian and/or vehicle sensors (also known as detectors or loops). Although the vehicle detectors are quite sensitive, some bicycles may not have enough metal in them to be detected unless they are positioned directly over the wired loop. To ensure that bicycles are detected the most sensitive part of these loops are marked with three yellow dots, about 10 cm in diameter and 50 cm apart. Cyclist should position their bicycles over these dots in order to make sure that they are detected.

Walk Signal

The pedestrian signal sequence begins with the “WALK” indication. The walk light indicates to pedestrians they are permitted to begin their crossing. In general, the standard duration of the walk signal is seven seconds, however in some cases it may be greater under different modes of signal operation.

This duration is not related to the crossing distance of the intersection, It simply indicates to pedestrians that it is safe to start crossing.

Don’t Walk Signal

The flashing “DON’T WALK” signal follows the “WALK” indication and is displayed before conflicting traffic movements are permitted to start. The duration of the flashing "DON'T WALK”, amber and all-red enable a complete crossing of the roadway. Additional time is provided at intersections utilized by a large number of young children, senior citizens or disabled persons. Pedestrians who are in the crosswalk when the flashing "DON'T WALK" starts have sufficient time to complete crossing before green is displayed to opposing traffic.

Steady Illuminated “DONT WALK” Signal - indicates pedestrian should not enter the crossing.

Push Button for Sequencing

For traffic/pedestrian-actuated signals the Walk/Flashing Don’t Walk sequence is only displayed if the push button is pressed.

If no buttons are pressed, then the “WALK” and the flashing “DON’T WALK” are not displayed.

The side street green time duration is determined by vehicular traffic and it can be significantly lower than the time required to cross the roadway. Always push the button to ensure you have enough time to cross the roadway safely.

Newly constructed or replacement traffic signals in the City of Ottawa are built to include Accessible Pedestrian Signals (APS) to comply with the Design of Public Spaces Standards of the Accessibility for Ontarians with Disabilities Act, 2005 (AODA).

What are APS?

APS are devices that use audible, tactile, vibrotactile and visual signage methods to assist all pedestrians, including people who are blind, visually impaired or deaf-blind to safely cross city streets.  

Do they beep?

Yes. APS signals emit a steady and constant beeping sound, known as a locator tone (listen), to make the push button easier to find for people with limited sight. The locater tone is calibrated so that it is heard only within a few steps from the crosswalk.

How do you activate an APS?

APS are activated similarly to any signalized intersection currently equipped with a push button. To activate, simply press the “raised tactile arrow button” once and wait for the walk signal to appear.

How do you activate the APS audible component?

The APS audible component is also activated similarly to any signalized intersection equipped with a push button. Holding the “raised tactile arrow button” down for at least three seconds triggers a vibration and a sound to inform pedestrians that the audible component has been triggered; the sound is heard when it is safe to cross.

The Cuckoo sound (listen)  indicates the right-of-way pedestrian crossing for north-south travel, while the Canadian Melody sound (listen) for east-west.

If the audible Cuckoo or Canadian Melody is triggered, the push button with the raised tactile arrow pointing in the direction of crossing will also vibrate once the walk signal appears.

Further information on APS design and layout can be found in the City of Ottawa’s Accessible Design Standards.

Where are APS Located in Ottawa?

Search the list of locations equipped with Accessible Pedestrian Signals or signals with audible components.

For more information about Accessible Pedestrian Signals, please e-mail 311@ottawa.ca

Amber-lock is a traffic signal software feature that improves the intersection user experience at signalized intersections where a busier main street crosses with a lower-volume side street. It ensures cyclists who wait on the side street of the intersection will receive a green traffic signal if they remain at the stop line until the main street amber signal has terminated.

This reduces the instances of ‘red reverts’ experienced by cyclists waiting at side streets, occurring when the intersection signal displays a red light in all directions, but then resumes to a green light for the main street when detection of a vehicle or bicycle, on the side street, is lost prior to turning green.

As of 2023, approximately 250 intersections in Ottawa meet the characteristics, and have the amber-lock feature installed.

The City undertakes investigations of intersections and mid-block sections to determine the need for pedestrian signals if the minimum warrants are satisfied as defined in the Ontario Traffic Manual.

An eight hour pedestrian and cyclist survey is conducted and collision data is reviewed. Pedestrians and cyclists are counted by type of person (child, youth, senior) and by delay to these persons in crossing the subject roadway. The highest six hours of collected data is tested against the pedestrian signal warrants.

Warrant requirements include:

Both of the following warrants must be fully satisfied before a location can be recommended for a pedestrian signal.

• Minimum Pedestrian Crossing Volume Warrant: The total of the highest six hour pedestrian volume crossing the major road at an intersection or mid-block location meets or exceeds the minimum value required based on the 12 hour vehicular traffic volume on the major road.
   
• Minimum Pedestrian Delay Warrant: The total of the highest six hour volume of pedestrians experiencing delays of 10 seconds or more in crossing the road meets or exceeds the minimum value required based on the six hour volume of pedestrian crossing volume of the volume warrant

Consultation

• The Ward Councillor is consulted for all locations that prove warranted
   
• If roadway modifications are required, public notification/consultation is conducted as set out by the Ontario Municipal Act

• Subsequent public consultations will be held if geometric changes on the intersection or an impact on local traffic movements is anticipated

• Council approval, through the capital budget process, is required for all installation

The City undertakes investigations of intersections to determine the need for new or enhanced traffic control signals if the intersection satisfies the minimum warrants as defined in the Ontario Traffic Manual.

Warrant requirements include:

1. Considerations of two types of road conditions:

• Restricted flow conditions, normally encountered in urban areas where the traffic volumes approach or exceed the practical capacity of the road
• Free flow conditions, normally encountered in rural areas where operating speeds are generally higher

2. Review of intersection including:

• Minimum vehicular volumes approaching the intersection
• Delay to cross traffic at the intersection
• Total number of reportable collisions at the intersection
• Combination of two of the three warrants meet at least 80 per cent of the signal warrant

3. A minimum warrant of 100 per cent must be satisfied to recommend an installation.

Consultation

• The Ward Councillor is consulted for all locations that prove warranted
• If roadway modifications are required, public notification/consultation is conducted as set out by the Ontario Municipal Act
• Subsequent public consultations will be held if geometric changes on the intersection or an impact on local traffic movements is anticipated
• Council approval, through the capital budget process, is required for all installation

For inquiries related to traffic signal operations please email: 311@ottawa.ca