We had known for some time that the alledged benefits of roads were overstated. The extracts below are from the most recent report.
- The Impact of Road Projects in England, Transport for Quality of Life, March 2017. Commissioned by CPRE.
This study examines the impacts of road schemes on traffic, the environment (focussing in particular on landscape, biodiversity and carbon emissions), the economy, road safety and land use.
It draws upon evidence of short-term impacts (between one and five years after scheme completion) from over 80 road schemes, published by Highways England1 through its Post-Opening Project Evaluation (POPE) process. This is supplemented by long-term evidence from four road schemes that were completed between 13 and 20 years ago: the A34 Newbury Bypass, M65 Blackburn Southern Bypass, A46 Newark – Lincoln dualling and A120 Stansted to Braintree dualling.
The impacts of road building
Evidence from 13 road schemes (nine randomly selected from all available POPEs, across all English regions, and the four case study schemes) is consistent with the conclusion that road schemes generate traffic. Average increases over the short run (3-7 years; seven schemes) were +7%. Average increases over the long run (8-20 years; six schemes) were +47%. These were increases over-and-above background traffic growth (measured by county and regional trends), and in most cases were across a screenline, to rule out reassignment effects. Exclusion of schemes where screenline data was unavailable reduced these averages, but the difference was small.
More than half of road schemes for which a POPE is available (49 out of 86) affected an area that had a local or national designation for its landscape, biodiversity or heritage. Many schemes had multiple impacts.
Evidence from the four case study schemes suggests that the impacts of road schemes on landscape and biodiversity are long-lasting.
The effect of road schemes in generating traffic means that they also cause substantial increases in carbon emissions, probably systematically and significantly underestimated by the POPE process because of its failure to recognise generated traffic.
Of 25 road schemes justified on the basis that they would benefit the local economy, only five had any evidence of any economic effects. Even for these five, the economic effects may have arisen from changes incidental to the road scheme, or involved development in an inappropriate location, or involved changes that were as likely to suck money out of the local area as to bring it in.
Where a road scheme was justified on the basis that it would support regeneration of an area with a struggling economy, it was common for economic development following completion of the road scheme to be slower than expected, or not to materialise at all, or to be of a type which offered little benefit to the area concerned.
Where a road scheme was justified on the basis that it was needed to cater for current and future traffic in a ‘pressure cooker’ area with a buoyant economy, it was common for the scheme to be followed by much development in car-dependent locations, causing rapid traffic growth and congestion on both the road scheme and the pre-existing road network.
Some road schemes were justified on the basis that by reducing journey times, they would increase the number of jobs that were accessible to local people, or increase the potential workforce able to access major employment sites, or create thousands of new jobs. There was no evidence of measurable economic benefit from these schemes.