Travel Time Monitoring in Urban Areas – Survey Design.

This paper describes the design of a survey to measure variations in travel time and their possible causes and to develop cost effective travel time survey instruments. After describing the background and objectives of the study it reviews in turn the uses to which travel time data can be put and the resulting survey requirements, the factors which might cause variations in travel time, and the available survey methods. The survey strategy outlined in the final section is based on these reviews. It concentrates on inbound peak period travel times over five radial routes in Leeds, and uses number plate matching to measure inter-vehicle variation, and moving vehicle observer methods to measure inter-period variation. Two other methods are also employed. The surveyperiod is spread over 14 months to identify seasonal effects, but uses a Latin Square design to reduce the scale of the data collection task.