Descriptions of the Measures

This report details the road network length and number of journeys by ONRC.

The length of the network, also known as the Centreline Length, is the sum of the length of Road Section  that have the appropriate values for road type and owner type for your network. This is broken up by ONRC classifications.

Lane Kilometres are calculated from the length of the Road Sections within the classification multiplied by the number of Lanes recorded on each Road Section.

Journeys travelled, technically called Vehicle Kilometres Travelled (VKT), are measured by multiplying the volume of traffic on a road by its length. The volume of traffic is taken from the Annual Average Daily Traffic (AADT)  for the Road Section . VKT is calculated as follows: VKT = Section Length in kilometres * Traffic AADT Estimate in vehicles per day * 365 days in a year. This shows where most customer journeys are made.

Road sections that are not applicable to the One Network Road Classification can now have their ONRC category set to 'Not Required' in Road Assessment and Maintenance Management. The total length of any ONRC 'Not Required' road sections is also reported in the Network Characteristics report.