Project: Forecasting Travel Time Variability in Urban areas

Reference: R180

Last update: 15/08/2013 13:44:41


This project will deliver a set of models in a report that will enable users to model travel time reliability.


. Collect or identify suitable datasets such as ITIS or HATRIS and carry out preliminary analysis of the dataset to ensure that they are fit for purpose.
. Estimate travel time variability as a function of traffic flows and journey time. It is likely that relationships will vary between urban areas or between different routes in urban areas. This analysis should also be carried out separately for London to reflect the impact of congestion charging.
. Estimate the relationship above for a neutral month and a holiday period where there is a significant fall in demand, for example the holiday period of August.
. Produce worked examples of the implementation of the relationships developed above in the appraisal of three live schemes with different policy intervention.
. Produce a written report on the modelling and appraisal of travel time reliability based on the research, current knowledge and best practice. The Department plans to release updated guidance in February 2007, based on existing research. This report will be used to further revise the February 2007 guidance.
. Produce a report which provides recommendations on how the supply side relationships developed could be incorporated in demand and supply models.


This project aims to improve our understanding of the impact of congestion on travel time reliability as the level of demand for road space interacts with the level of service provided. The project would give us improved methodology to better assess and appraise reliability as a result of interventions. Better informed methods for modelling reliability would result in better forecast measures of congestion agreed as PSA targets.


Hyder Consulting (UK) Ltd
10 Medawar Road, The Surrey Research Park, Guildford, Surrey, GU2 7AR

Contract details

Cost to the Department: £80,000.00

Actual start date: 19 February 2007

Expected completion date: 30 September 2007