Following the Cabinet Secretary's answer that a full set of validated annual air quality data for the extended 50mph zone from Port Talbot to Swansea on the M4 will not be available until September 2019 at the earliest, will he confirm when the temporary 50mph speed restrictions will be lifted?
Last week, we published the final Welsh Government Supplemental Plan to the UK Plan for tackling roadside nitrogen dioxide concentrations. The plan contains information on the work undertaken at the 5 locations on the roads that we manage, including details and a programme for the Action Plan Measures which for the M4 at Port Talbot includes continuation of the 50mph speed limit.
As set out in the Plan, it is anticipated that that the speed limits will remain in force for as long as they are required to maintain air quality standards. Accordingly, it is not possible to confirm the duration of the limits at this stage. However, the 50mph speed limits will be reviewed periodically to determine whether they are still necessary.
The Plan also contains details of the Precautionary Retained Measures that may be required should the on-site monitoring record NO2 values higher than predicted in the DEFRA Pollution Climate Mapping (PCM) model.
The plan can be found at the following link: https://gov.wales/topics/environmentcountryside/epq/airqualitypollution/airquality/?skip=1&lang=en&