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The proposed, and now cancelled, extension of the M4, represented the single largest infrastructure investment in the Welsh Government’s pipeline. Over two projects NEF Consulting supported the Future Generations Commissioner (empowered by the 2015 Well-being of Future Generations Act) with analysis examining the project’s impact on future generations across social, environmental, and economic outcomes.  We grounded our work, which included quantitative modelling of inequality and carbon impacts, in a multi-criteria analysis methodology.


NEF Consulting was asked to assess the proposal for an extension to the M4 motorway around Newport, and the potential alternatives, against the criteria of the Well-being of Future Generations Act. The Future Generations Commissioner wanted to ensure that the preferred option represented the best value towards achieving the seven wellbeing goals set out for Wales.

The proposed route would have cost around £1.4 billion, and plowed through four protected areas (Sites of Special Scientific Interest).

NEF Consulting highlighted the scheme’s many contradictions with national and local wellbeing objectives, and ultimately contributed to the evidence base which led to the scheme’s cancellation.

You can download the full report here:  Transport Fit for Future Generations

You can download the NEF Consulting report here: Alternative Transport Options for South Wales

Read our original blog here.