How important are environmental factors in the case for high speed rail? A comparison of the United Kingdom and Spain

High Speed Rail (HSR) offers the potential to provide enhanced regional connectivity within Europe whilst countering the increase in short-haul flights. The reduced emissions of HSR compared with short-haul air trips is an important part of the argument for an expanded network yet such an assessment is only partial in its consideration of the full range of environmental impacts. There are substantial financial and natural resource costs of constructing HSR and, to better understand the degree to which the environment is indeed important in the decision-making process this paper reviews the processes for assessing the benefits of HSR and reviews and their practical impacts, using four case studies. The paper begins by setting the policy context for High Speed Rail with some introductory statistics on the current state and proposed expansion of the European network. Next, the paper reviews and contrasts appraisal practice in the UK, Spain and at a pan-European level to consider the key stages and components of ex-ante project appraisal. The paper then reviews four case studies (two each from the UK and Spain) to explore the economic case for HSR and within this the importance of environmental benefits in the final decision. The degree to which the environmental impacts of HSR have influenced route selection is also identified. The paper concludes that the economic case for the reviewed HSR schemes is typically not strong relative to other potential investments in transport. The environmental benefits form only a small proportion of the net benefits and, given the high capital cost of the schemes, if the argument to invest in HSR is largely environmental then there are many other investments which would deliver bigger environmental savings with much better returns on investment. The treatment of environmental impacts within the appraisal process is clearly identified and, whilst the guidance in Spain requires some further development, there are clear examples of the extent to which Environmental Impact Assessment has influenced route alignment and route choice. On the basis of these case studies it appears that HSR has the most to offer in journey time benefits to travellers. As a pro-environmental policy it has significant limitation.