The Outline Business Case (OBC) set out the process for determining the best performing option to achieve compliance in the shortest possible time, which was determined to be a GM-wide Clean Air Zone Class C (CAZ C), targeting non-compliant buses, coaches, taxis, private hire vehicles, HGVs and LGVs. An assessment of the GM-wide CAZ D option is included in the OBC and the Option Appraisal Report. This was further explored in analysis carried out post-OBC to meet JAQU's requirements, which concluded that a GM-wide CAZ Class D (inclusive of private cars) was not likely to bring forward the date of compliance with the legal limit value for NO2 in Greater Manchester from that which would be achieved by implementing a CAZ Class C.
As set out in the Technical Note 17: Evidence supporting the decision not to progress with a GM-wide CAZ D, a scheme affecting private cars on this geographical scale is unprecedented – GM covers 1,280 km2 whereas in comparison the CAZ D (incl. private cars) scheme proposed in Birmingham covers just 8km2 . In order to develop, consult upon, and deliver such a scheme, a considerable volume of further planning activity would be required, encompassing research and data collection; modelling and analysis; policy development; scheme design and impacts assessments, amongst other activities. These activities would delay the implementation of the GM CAZ to such an extent that this option would achieve compliance with legal AQ Limit Value at a later date than the proposed CAZ C. It would not therefore achieve the primary objective of the GM Clean Air Plan (GM CAP), which is to achieve NO2 legal compliance in the shortest possible timescales.
Furthermore, a secondary objective of the CAZ is to minimise the risk of significant unintended negative economic, social or environmental consequences resulting from the implementation of the GM CAP. Greater Manchester contains some of the most deprived areas in England. Across GM, some of the most deprived areas have poor public transport accessibility and in these areas people are more likely to own a non-compliant vehicle. Those on low incomes, with little or no savings, or with limited access to credit may not be able to afford to upgrade to a compliant vehicle, or to pay the charge. There is a significant risk that the costs imposed by a GM-wide CAZ D could force people out of employment or education, as well as limiting people’s ability to travel to see their friends and family. In turn, this could lead to social isolation and hardship. A GM-wide CAZ D is therefore likely to have dramatic socio-economic ramifications across the north-west region and country as a whole and would require mitigations which are unlikely to be feasible.
This analysis is not materially affected by Covid-19 or other recent developments.