Institute of Transport Studies, University of Leed
Abstract
This report outlines work carried out to assess the factors that, in the medium and long term, may influence motorists' mode choice in the Greater Nottingham area. This work was based on four Stated Preference (SP) experiments that examined the choice between car and ordinary bus, car and bus-based park and ride, car and express bus and between departure times for car users. Just over 6,000 self completion questionnatres were distributed at random to residents in 28 wards. Over 1.700 usable responses were returned. representing a response rate of 29%. Despite a number of problems, a series of four strategic forecasting models were developed. These incoporated some important findings including that motorists value delay highly, value parking costs more highly than petrol costs and value adjusting their departure time less highly than in-vehicle time. The four forecasting models were then used to examine five scenarios; the introduction of park and ride, the effect of projected 2001 road traffic speeds, the effect of petrol cost increases, the effect of parking cost increases and the effect of decreasing bus in-vehicle time. Although there were a number of technical difficulties. our forecasts suggest that decreases in speeds, parking costs and petrol costs will not halt the growth in road traffic but will slow it down. Where possible motorists are more likely to change the time of theirjourney than theirmode. For dramatic changes in mode split both a big stick and big carrot are probably required. The big stick might be provided by some of parking control or road pricing, whilst the carrot might be some form of a high quality, fast bus network (or indeed other forms of public transport with a segregated right of way). The role of park and ride is likely to be relatively marginal but may be worth pursuing if part of an overall traffic management policy. There was little evidence from our models of there being any critical "thresholds" or "trigger points". However, many of the processes we have examined seem to have cumulative impacts and our forecasts identified the doubling of car journey times as being a possible "catalyst" which is likely to be achieved in the early part of the next centur
