The long-term social benefits of public transport

Purpose and goal

This project aims at in a case study of the Stockholm Subway valuate how important the benefits of the rail investments long-term structuring effect are in urban areas. Thereby, the social benefits of public investment will in the long term be described better. The project will thus contribute to new knowledge about the comparability of CBA:s for road and rail objects.

Results and expected effects

The cost-benefit analyses (CBA) in the transport sector are often criticized in particular that the benefits of large rail investments are underestimated. An often mentioned example is that the construction of the subway in Stockholm would not have given a social net surplus. In the ongoing Swedish national investment planning, however, one conclusion is that the CBA:s are mostly accurate, but that there are four weaknesses in the methodology that may be of importance especially in densely populated areas. The main deficiency is that no account is taken of rail investments long-term structuring effect on the location and population in urban areas.

Approach and implementation

The dynamic localization model Landscape, developed at KTH, will be used to forecast how the Stockholm traffic and its population and location would look like today if the subway had not been built. The forecast will start in 1950. As a comparison we will make a scenario where the subway is built at the same pace as in the real world, where we check that we on a gross level recreates Stockholm as it looks today. A comparison between scenarios with and without the metro will then display the social benefits of the subway, through its impact on distance travelled, travel times, modal split, external effects of car traffic (congestion, emissions and accidents), labour market and productivity.