Evaluation of a national congestion charging system

In work undertaken for the Commission for Integrated Transport, the authors have demonstrated that a national road user charging system could be developed that would make more efficient use of road space. The system could, in principle, charge motorists on a distance basis for every part of the road system, with charges varying by time of day and level of congestion, avoiding the issue of diversion of traffic onto unsuitable roads that would arise if charges only applied to the motorway system. This ‘peak-pricing’ mirrors the way we pay for other utilities such as telephone and electricity. The system could be ‘revenue-neutral’ such that the funds raised through the charges are balanced by reductions in vehicle excise duty and/or fuel tax. Alternatively, subject to Treasury agreement, variants could hypothecate some of the funding to transport improvements. The system could bring benefits to a large number of low-mileage drivers and rural residents who depend on their cars but impose little on others because they tend to drive in non-congested conditions. It would encourage drivers in congested conditions to reconsider whether their journey is necessary, whether it could be made by another mode or at a less congested time of day. The paper describes the findings from the research work, highlighting the technical, political and practical issues, and providing further insights into the impacts of such a scheme.