The Government is keen to make road-building a core part of its plans to stimulate economic growth. They are, however, finding it difficult to get very much built. There are good reasons for this.

Experience shows that new roads are ineffective at tackling congestion. They also have big negative effects on public health and greenhouse gas emissions. While fixing problems like potholes is often popular with people, ploughing up the countryside to build new roads is not.

Undeterred, the Government has published draft planning guidance which seeks to justify its road building ambitions. The draft National Policy Statement on national road and rail networks (NPS) calls for more tarmac while exempting roads from climate change targets, effectively gagging anyone who wants to raise the climate impacts of building new roads.

The draft NPS is very clear about the perceived need for such action. The draft argues “it will not be sufficient to simply expand capacity on the existing network and so some new road alignments and corresponding links will be needed.” It predicts that traffic will increase by 40% between 2010 and 2040, and sets an objective of reducing congestion by 40% over the same period.

This kind of growth in car use has been predicted for two decades, but has never materialised. By most measures, car travel is actually falling with total vehicle miles lower now than a decade ago. Distance travelled per person per car is also declining and the annual distance travelled per car is now 11% lower than it was in 2003.

If the demand is illusory, the impact of major new road building is very real. Around a quarter of the UK’s greenhouse gas emissions come from transport, yet rather than rein in the contribution road transport makes to this, the NPS contains a very public dropping of the requirement for road building to not increase emissions. The government’s desire for new roads would be allowed to trump national and international conservation interests, too. Proposals such as the dualing of the A303 would carve through the Blackdown Hills Area of Outstanding Natural Beauty and land adjacent to Stonehenge.

Social impacts are concerning too, as the kind of development that new roads lead to tends to be car-reliant, having negative repercussions for our town centres and for the millions who do not have access to a car. Far better would be policy to promote more sustainable options, which would have clearer benefits for the economy and communities.

There is a case for improving transport planning using a National Policy Statement. In its draft form, however, the NPS just repeats the government’s ill-considered desire for new roads. There is much work to do before we get to the final document which promotes evidence-based decision-making on transport.

James MacColl is head of campaigns at Campaign for Better Transport

Follow him on Twitter @CBTransport