Chapter 19 Scheme appraisal

This chapter details the appraisal process to be followed for highway schemes and associated local authority transport strategies and public transport schemes. This process is based on the Government's New Approach to Appraisal (NATA), augmented by NATA Refresh in 2009, which has been developed for two main purposes. Firstly, to identify a preferred choice between different options that solve the same problem(s); secondly, to prioritise different highway proposals. Where transport-related matters are the responsibilities of the Welsh Assembly, Scottish Executive or Northern Ireland Assembly, NATA principles have still been adopted. Transport Scotland has, however, issued Scottish Transport Appraisal Guidance (Scot-TAG) and the Welsh Assembly has similarly issued WelTAG, both based heavily on NATA but with minor changes. Scheme Appraisal procedures in Northern Ireland are based on NATA.