Short-term Forecasts of Travel Time and Incident Risk As Tools of Proactive Traffic Management

In managing the road network, taking action before traffic conditions become congested is often a more effective solution than just reacting to congestion as they take place and are observed. This kind of approach to transport network management is generally referred to as proactive traffic management. To be able to manage traffic proactively, information about the status of the traffic flow (e.g. average speeds, travel times) is needed. This information includes short-term forecasts of the traffic situation. In Finland, the Finnish Transport Agency is searching for a method that would give a situation-aware overall understanding of traffic on the road network at any given time to support the operative work of traffic management operators at the Finnish traffic management centres (TMCs). This understanding, or overall picture if presented in visual from, should also include short-term prediction of the traffic situation. Because the information about the predicted state of the traffic network would be used in operative traffic management activities, it is essential that the approach be practical, the output of sufficient quality, and information on the quality of forecasts easily accessible. Specifically, a key element in proactive traffic management is the prediction of travel time in different traffic and road weather circumstances. Certain combinations of traffic flow and road weather conditions could be more likely to result in incidents than others. In addition, ways to monitor and identify risk factors on the road network should be developed to be able to anticipate the potential emergence of accidents and other traffic incidents and to be able to predict their likely consequences. This paper will present the results of the research and development work to be finalised during the spring of 2013.