Modelling undertaken by GM has shown that NO2 concentrations are predicted to exceed the legal Limit Value in all 10 Greater Manchester local authorities. As such, a comprehensive plan for the whole of Greater Manchester is required, in recognition that travel and emissions are not confined within district boundaries.
All 10 GM local authorities are now subject to a ministerial direction requiring them to implement a charging CAZ Class C across the region in order to achieve compliant levels of NO2 concentrations in the shortest possible time and by 2024 at the latest, providing considerable health benefits at the lowest cost to society and the economy.
Transport modelling has shown that whilst a large volume of traffic is associated with accessing urban centres, there is also significant use of the local road network to access the motorway for trips spread around Greater Manchester and beyond.
A GM-wide approach will also avoid displacement, which could occur if action was undertaken in some districts and not others. Exclusion of some areas of GM could potentially cause changes in travel behaviours and worsen the situation in the areas that are excluded from the zone.
This answer has come from the Response to Consultation. More information can be found here: GMCAP Response to Consultation Report v1 (ctfassets.net)