Road networks throughout the world are experiencing ever increasing levels of stress. The continuing rise in travel demand means that planned events such as network maintenance, new road construction and bridgeworks, and unplanned events in the form of traffic incidents and peak period congestion frequently result in undue delay, unreliable journey times, reduced safety, environmental damage and energy wastage. It is increasingly becoming accepted that strategies based on enhanced Driver Information Systems can bring about significant improvements in both individual driver route choice as well as wider network performance. The paper discusses both the operational and system design considerations in order to ensure that the information presented to drivers reflects, in a reliable way, current and expected traffic conditions in the network. Since such systems require relatively high levels of capital and operating expenditure it is important that a method is established both to estimate the possible level of benefits prior to investment decisions being made and to measure network performance as an integral part of the operating procedures. The paper discusses the key issues that have to be addressed in establishing a comprehensive evaluation procedure. (A)
Abstract