Optimal Land Use–Transport Strategies

There has been growing interest in Europe in the development of integrated transport strategies, in which individual policy instruments are combined to complement one another and to achieve improved performance against a given set of policy objectives. This paper applies an optimization procedure to identify optimal strategies for packages of transport policy instruments without, and then with, constraints on finance and targets for global warming and safety. Some exploratory tests have also been carried out on land use strategies, and they are reported here in brief. Results demonstrate that the methodology is robust and can be applied with different transport models and with constraints applied both to policy instruments and to objectives. All optimal strategies found involved substantial reductions in fare levels throughout the study area. Where it was not possible to change fares, the strategies were substantially less effective when measured against the objectives. Most optimal strategies involved increases in public transport frequencies, although their scale varied between cities. All optimal strategies included peak-period cordon charges to enter the city center, though the optimal level varied between cities. Financially constrained strategies were found to involve smaller fare reductions and higher cordon charges; in some cases frequency increases were smaller. These constrained optima still performed well; the greatest reduction in benefit was only 15%. The net present value of the benefit generated was about €2,000M (€1 = $1.20 US, 2005) in Edinburgh and more than €4,000M in Leeds, United Kingdom. The impact of transport strategies on land use was small, and development constraints had to be used to reverse urban sprawl.