The growing imbalance between supply and demand for road space in many regions has placed increasing pressure on road authorities. There are rising expectations of what the authorities and road network operations should achieve. Traffic incidents and congestion in one locality can quickly impact on road users elsewhere, with the result that a wide-area, integrated approach is needed. Increasingly road network operations are required 24 hours a day, 7 days a week.
Five main areas of activity can be identified in Road Network Operations:
Each of these activity areas has aspects that are important to the quest for a better level of service for the road user, but none of them holds any real precedence over the others.
1. Network monitoring is necessary for the preparation of adequate operating, maintenance and capital renewal budgets, establishing policies and procedures and overall strategic network planning. The road operator or responsible authority must have continual access to quantitative and qualitative information on traffic and the roadway. An additional benefit is to provide users with information and advice on alternate routes by performing expert analysis on traffic volumes, distributions and fluctuations. Intelligent Transport Systems (ITS) technologies provide the basis for monitoring road traffic and network status data close to real time. Increasingly day-to-day data on traffic conditions is gathered through direct contact from travellers and from mobile phone data (See Monitoring Activities)
2. Network operations are needed in order to manage and maintain the road network as effectively as possible and implement adequate operational measures. Activities include emergency response, weather related services, planned interventions and automatic enforcement, all imperative to mitigating and reducing the frequency of crisis situations. ITS helps in maintaining the viability of the road network by providing users with credible, real time information on unpredictable or forecast events. Reliable information helps to secure user compliance with control measures necessary for events such as adverse weather, natural disasters, major sporting and cultural events and evacuation in the case of emergencies (See Operational Activities)
3. Traffic control is there to minimize congestion and user disruption, for example by distributing all planned roadwork over a reasonable space and time period. This is done through information gathering, analysis, development of traffic management plans and then implementing and communicating this to the user. The risk of gridlock can be minimised by computerised signal control and active traffic management. Coordinated action by various authorities and services can reduce the impact of otherwise-disruptive events (See Traffic Control)
4. Demand management can create conditions that will lead to a beneficial reduction in traffic levels in various ways, for example by advising the use of alternate travel periods, travel modes and routes in response to a forecast drop in road network service levels. Congestion can often be eased by efforts to encourage users to alter the timing of journeys to spread traffic over time. Tolling technologies are also used a means of influencing peak demand through road pricing or a congestion charge. Fees can automatically be raised during peak periods and lowered during periods of lighter traffic, as well as promoting use of public transit during rush hours. The same technologies can be used for parking payment and access control (See Demand Management)
5. Traveller and road user services can also increase the efficiency of the road network by enabling information exchange between partners that is then disseminated to road users. Identifying blockage points and organizing or reorganizing to ensure the system functions effectively is key for activities such as winter maintenance; reducing the time required to restore normal conditions, minimizing disruption to the local economy and improve safety, as well as redirecting certain types of traffic, such as removing heavy goods vehicles (HGVs) from problem areas. Advanced user information also provides comfort to travellers who need to feel confident and secure in their journey. Typical applications include route confirmation, journey time estimates, clear direction signs and advice on approaching interchanges and connections. This kind of information is commonly delivered in-vehicle through satellite navigation systems (See Travel Information Systems)
The benefits of Road Network Operations apply to all road users and the public at large. They include improved safety, minimized adverse impacts on the environment due to reduced congestion, improved mobility and energy efficiencies, as well as enhanced economic productivity from reduced travel times (See ITS Benefits)