Greater Manchester has considered a wide range of measures that could help reduce roadside NO2 levels.
We started off with a longlist of 96 different options and used government guidelines to shortlist the most effective measures. These measures were wide-ranging and included, for example:
From the shortlisted measures a number of options were developed. We assessed these options using the Government’s ‘primary and secondary success criteria’.
The Government’s primary success criteria are:
Three options were identified which would deliver compliance by 2024 in line with these criteria:
1. A Greater Manchester-wide Clean Air Zone to include non-compliant cars within the inner ring road, and wide-ranging support measures
2. A Greater Manchester-wide Clean Air Zone with an Ultra-Low Emission Zone within the inner ring road, and wide-ranging support measures
3. A Greater Manchester-wide Clean Air Zone and wide-ranging support measures
Having identified these three options, the Government’s secondary success criteria were applied to arrive at a preferred option. These include consideration of the wider impacts of the proposals and the cost to implement them.
This process led to the current Greater Manchester Clean Air Plan proposals being identified as the best way forward for tackling Greater Manchester’s NO2 issue. Modelling shows that they would achieve the required reduction in NO2 levels in the shortest possible time and in the most cost effective way, while minimising the wider impacts on Greater Manchester’s people and economy.
Once the Greater Manchester Clean Air Plan is in place, it is estimated that every site within Greater Manchester will have NO2 within the legal limit of 40 micrograms per cubic metre (µg/m3) by 2024. If no action was taken the estimated date of legal compliance is 2027.
You can find out more detail of the assessment process, the data and methodology in the Options Appraisal Report which can be found with the other GM Clean Air Plan Outline Business Case documents.
More work is being undertaken to understand the impacts of the proposals at this stage. The Greater Manchester Clean Air Plan Outline Business Case includes an Equality Impact Assessment.
The ‘Clean Air conversation’ will help us to identify any additional issues and further develop the Equality Impact Assessments for the detailed proposals. These will be set out in the subsequent statutory public consultation.