Reexamining Old Problems with New Methods: Portbury Revisited

It is now twenty years since the Ministry of Transport examined the feasibility of constructing new harbour facilities at Portbury, Bristol. Part of that analysis was based on the use of a gravity model. Since 1966 significant progress has been made in many aspects of urban and regional modelling. There is now a basic competence in many aspects of modelling which could not have been envisaged in the early days. So far, however, there have been few empirical applications of these latest techniques. The original Portbury problem and its associated data sets provide an excellent opportunity to examine the new set of models in a real public-planning context. The aim here is not to assess critically the original Portbury decision per se—this is done in a number of other studies—but more to use the models in an illustrative way showing how improvements to existing appraisal methods can be made with careful thought and application.