Latest Developments in Appraisal and Practical Evaluation of Intelligent Transport Systems
P Riley, Jacobs Consultancy, CZ; L Pennycook, A Martin, Jacobs Consultancy, UK
transport, intelligent transport systems, micro simulation, monetization, transportation management, planning, evaluation, journey times, reliability, benefits
Intelligent transport systems (ITS) are becoming an increasingly mainstream element of traffic and demand management across the whole of Europe and are at the same time consuming an increasing proportion of transport infrastructure investment and operations budgets, with European investment now in the order of hundreds millions of Euros each year.
Depending on the context of the problem being addressed, ITS can contribute significantly to congestion reduction, improving safety, reducing incidents and, to a lesser extent, to the reduction of emissions. Monitoring of controlled motorways in the UK has for example shown reductions of over 15 % in injury accidents. However, a badly conceived (oversized, misplaced etc.) ITS scheme can be a poor investment.
The appraisal of ITS benefits in the support of optimising complex ITS solutions and supporting public investment decisions is an underestimated task with still limited consensus on appraisal techniques and a small and sometimes seemingly conflicting body of empirical evaluation results. A sound and efficient appraisal of the benefits of ITS applications requires a well designed mix of appropriate modelling (for example to understand congestion impacts) and recourse to a suitable source of empirical impact experience (for example for accident and impact reduction and rerouting choice based on road side advice).
This paper will critically examine some of the latest ITS appraisal techniques, experiences and standard methodologies being used in both the UK and elsewhere in Europe, and will draws in particular on the authors latest experience in the use of micro-simulation techniques for congestion modelling and models for estimating accident, incident impacts and travel time reliability benefits.
Association for European Transport