ANOTHER LOOK AT LEITCH

Topics discussed at a seminar on the leitch report held at Bristol university's school for advanced urban studies are summarised. The leitch committees terms of reference appear to be too narrow in the light of the complete transport planning sequence. Problems need more explicit consideration before planning; before and after studies would also check on the performance of schemes. The desirability and effectiveness of the criteria to be used in any assessment method applied to trunk road planning were discussed. The main differences in tannern's model and the regional highway traffic model (rhtm) are examined. Because of the large amount of uncertainty of the models used in forecasting it was thought that a range should be used with probability values. The consequences of a forecast being 'wrong' must be considered. Many people thought extra resources would be needed to cope with increased preparation work. The possible relevance of the report to the assessment of local road schemes was discussed; it was felt that the committee could have included urban roads in their investigation. /TRRL/