The environmental impact of road transport and road transport infrastructure on the environment is one of the big issues facing transport planners and policy makers the world over. Economists have suggested that appraisal processes such as COBA undervalue the environmental impact of new road schemes because environmental impacts are not directly included in the monetary cost-benefit process, i.e. they are externalised. Additionally critics state that the overall evaluation is complicated by the number and type of qualitative measures of environmental impact, this leads to confusion and non-standardisation in the decision making process. In answer to these criticisms it has been suggested that monetary values of enviromnental impacts should be directly incorporated into the appraisal process. This paper describes the use of Stated Preference (SP) for placing values on environmental impacts. Although SP techniques have been widely used for placing monetary values on factors such as journey time and ride quality, their use within the field of environmental valuation is new. The paper reports results from empirical research undertaken with respect to a By Pass scheme in Bedfordshire. The research was successful in gaining plausible and statistically significant monetary values for Road Safety and Air Quality and respondents were able to understand the SP experiments and the trade logically between Choice Scenarios. The paper reports on the difficulties of using SP to value environmental impacts, mainly problems arising from heterogeneity in the population with respect to valuations and the issue of the representation of attributes. For the covering abstract see ITRD E105584.


  • English

Media Info

  • Features: References;
  • Pagination: p. 279-90
  • Serial:
    • Volume: P434

Subject/Index Terms

Filing Info

  • Accession Number: 00796503
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • ISBN: 0-86050-325-9
  • Files: ITRD
  • Created Date: Aug 2 2000 12:00AM