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Traffic Control Signals

Traffic control signals are essential for the safe and efficient movement of traffic. They are used to designate right-of-way of conflicting movements. The Works Department currently operates and maintains over 470 traffic control signals. In addition, approximately 25 signals are added to the system annually.

The Works Department operates 24 hours a day, seven days a week, to ensure a safe and efficient road network. If you notice a problem with a traffic control signal, please report this trouble by calling:


Monday - Friday
8:00 a.m. - 5:00 p.m.

After Hours

Evening / Weekends / Holidays

The Traffic Engineering and Operations Division of the Works Department plans, designs, constructs, operates and maintains the traffic control signals in the Region of Durham, except for the traffic signals on rural provincial highways, such as Highways 7, 7A, 12, and 48.


The Works Department is responsible for the planning of appropriate traffic control when required. "Traffic Control" refers to the many methods by which engineers provide motorists with information to make the right decisions and avoid collisions. Providing safe and efficient intersection control is one of the primary mandates of the Traffic Engineering and Operations Division. Before a traffic signal can be added, or a two-way stop control changed to an all-way stop control, the need must first be determined. This need is based on criteria to ensure all users of the transportation infrastructure are considered and that public funds are not spent inappropriately.

The following is a list of some of the traffic control devices considered:


The Works Department is responsible for the design of traffic control signals, including:

  • Traffic signal heads [see photo]
  • Pedestrian signal head [see photo]
  • Signal poles [see photo]
  • Underground conduit [see photo]
  • Detector loops
  • Video detectors [see photo]

Installation and Maintenance

The Works Department is responsible for the installation and maintenance of traffic control signals and the associated peripheries, including:

  • All traffic control devices and associated data communication devices and lines
  • Traffic monitoring equipment at intersections, such as CCTV cameras
  • Preparing the specification of materials and tenders for construction
  • Inspecting the construction of underground conduit [see photo]


When an intersection is under construction, it may include:

  • The installation of a new traffic control signal
  • The modernization of the traffic control devices
  • The reconstruction of the intersection itself (geometric improvements)

When new traffic control signals are under construction, driving through the intersection may be confusing. Before the signals at the intersection are "energized", or turned on, the signal heads are bagged [see photo]to inform motorists that the signal is not yet operating. You should follow the existing traffic control device, whether that is stop signs or a police officer directing traffic. During the period that Region of Durham Works Department staff are energizing the signal, a police officer is on site directing traffic.

Operation and the Central Traffic Control System

The Works Department is responsible for a safe and efficient road network and uses the central traffic control system to provide maximum efficiency of the signal network, which comprises:

  • Planning, designing, and implementing the signal timing and phasing
  • Co-ordinating the signal timing of adjacent intersections
  • Scheduling and conducting regular signal timing updates on arterial roads
  • Responding to complaints and questions related to the operation of the traffic control signal
  • Reviewing roadway design for modifications and construction
  • Monitoring current traffic conditions and adjusting the signal timing to minimize delay
  • Designing, implementing, and monitoring the traffic signal timing for detours necessitated by construction, special events, or road closures

The Traffic Engineering and Operations Division constantly monitors the central traffic control system promptly addresses such issues as a traffic signal in flash, a signal timing problem, or lost communication between a traffic signal and the traffic control centre. The Region of Durham Works Department is constantly creating, upgrading, and maintaining the applications that support the traffic control software.

A Centralized Traffic Control System allows multiple traffic control signals to communicate with a central computer so that incidents, such as changes in traffic patterns or signal failures, can be quickly identified and managed. It provides the Region of Durham the ability to co-ordinate the timing of traffic control signals, and to reflect known and unexpected fluctuations in traffic flow.

As traffic volumes increase, so does congestion and delays resulting in driver frustration and disobedience of traffic laws. The goal of co-ordinating traffic control signals is to get the greatest number of vehicles through the signal network with the fewest stops and delays in a safe and comfortable manner.

Both economical and environmental benefits can be achieved with a well-managed traffic control system. They range from real savings in fuel consumption, travel time, reduction in airborne pollutants and improved traffic flow. Municipalities can delay the need for costly road projects by enabling more cars to travel on existing roads more efficiently with smoother, less interrupted traffic flow. Emergency services and signal maintenance operations can respond unimpeded to problems resulting in a safer environment for the travelling public.

The Centralized Traffic Control System communicates to each traffic control signal via dedicated telephone lines and Regional owned cable. Predetermined signal timing plans are stored in the central computer. Timing plan changes are sent to each traffic control signal on a time-of-day basis, or in response to unexpected fluctuations and changes to traffic flow. Traffic volumes, vehicle speeds and delay measurements are monitored automatically via permanent count stations to ensure the effectiveness of the system.