Detection and Confirmation

Detection of traffic congestion is primarily accomplished through the use of inductance loop detectors, or vehicle detectors, embedded in the freeway pavement. Vehicle detector stations are located at approximately 600 metres intervals which transmit traffic data back to the Traffic Operations Centre every 20 seconds. A central computer at the traffic operations centre constantly analyses the data using an incident detection algorithm. The central computer system will alert the operator of a suspected incident and request a confirmation.

Closed circuit television cameras provide the primary means of confirmation. These cameras are placed about one kilometre apart with full pan, tilt, and zoom capabilities, effectively providing 100% coverage of the roadway. Once the incident is confirmed visually, the operator will proceed with a specific response plan and notify the appropriate response services.

The goal of the incident detection and confirmation strategy is to dispatch an appropriate response in a timely manner. As a result, the incident can be promptly dealt with and removed from the freeway.