How to design effective road pricing cordons

This paper describes three approaches to cordon location design, a judgemental approach, an optimisation approach based on genetic algorithms and a short–cut approach which lies between the two. The genetic algorithm optimal single cordon generated benefits that were 80% higher than the best judgemental cordon for a simplified network of Edinburgh. The short–cut approach was developed from an observation that charging on only a few of the highest marginal cost links could result in a high proportion of the system optimum or first–best benefits. Initial results for Edinburgh and York have shown that the approach can achieve 93% of the genetic algorithm optimal cordon benefits with only a few model runs in the case of Edinburgh