National Highways Incident Delay Metric

May 17, 2022

City Science is pleased to announce that we have been appointed by National Highways (working in partnership with WSP) to develop a new Incident Delay Metric. The new metric will be an option for reporting by National Highways during the third road investment strategy period (RIS3), subject to successful completion of the development and validation stages.

Development of the new metric, which was a commitment of the Department for Transport (DfT)’s current second road investment strategy period (RIS2), will be more focused on the user experience and reflect the impact of unplanned incidents, such as collisions or asset defects, on people’s journey times using the Strategic Road Network.

We will achieve this through a detailed review and optioneering process of potential data sources and metrics to apply. This will account for the outcomes of a parallel detailed stakeholder engagement process including with internal National Highways teams and external stakeholders such as the DfT and Office for Road and Rail. Following the metric selection process, we will then develop a predictive model of how the metric is likely to perform in future.

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