Building a Sustainable Future - .PDF file.
The Acceptability of Road Pricing - .PDF file.
A major re-think on how infrastructure is planned, built and used is required as part of the national strategy to reduce greenhouse-gas emissions.
A report from the Institution of Civil Engineers (ICE) entitled Building a sustainable future says this requires a whole-life approach to carbon assessment, not solely assessing the carbon used in construction but balancing this with the carbon used during the operational lifespan as well.
In the case of the roads network this would mean considering the carbon emitted by vehicles using the road over its lifetime and finding ways to drive it down through innovative design choices.
Figures from 2009 show that 22 per cent of the UK’s total emissions came from transport with 62 per cent of that figure coming from passenger cars.
Looking forward, the population in parts of England is expected to grow by 20 per cent in the next 20 years and the Department for Transport estimates that by 2035 road use will have increased by between 40 and 50 per cent compared to 2003.
Existing roads are not likely to cope effectively with the increased number of users, particularly at peak travel times and the report sets out actions that may mitigate impacts on the environment and economy while considering the requirements of the motorist.
The report says that fossil-fuelled vehicles use more energy and therefore emit more carbon when they are forced to stop and start frequently, so making roads as free flowing as possible would have a significant impact on emissions.
Simultaneously, this would improve the economic and social performance of the asset by reducing congestion and travel times that have a detrimental impact on the economy.
Replacing roundabouts or traffic lights on the most heavily trafficked routes with grade-separated junctions that divert turning traffic using over-bridges would allow all other vehicles to continue uninterrupted.
Similarly, more energy is required to power a vehicle uphill than along a flat road, so levelling the gradient of roads would also reduce emissions over time.
Although achieving this type of ‘low-carbon’ road would require an upfront carbon and financial investment, it would be paid back over its operational lifetime by the carbon saved from vehicle emissions, as well as the economic benefits of a more efficient roads network.
Tim Chapman, chair of the report working group, said: ‘Roundabouts, traffic lights, steep gradients and other features that require vehicle engines to work harder all exacerbate carbon emissions.
‘It’s time we looked at addressing these “carbon pinch points” on major routes where a combination of relatively small, targeted interventions could make significant long-term carbon savings and improve the performance both socially and economically of vital infrastructure assets.’
Speaking at the launch of the report, Stephen Glaister, professor of transport and infrastructure at the Centre for Transport Studies at Imperial College London, added that introducing a charging system for peak road use could improve traffic flows.
This could be implemented by way of tolls, booking road use or pay-as-you-go schemes.
Click here to learn more about road pricing.