The poor state of repair of our urban and local roads, which account for 98 per cent of the network, were highlighted in the Asphalts Industry Association’s latest ALARM annual survey issued last month. The survey showed that more than 24,000 miles of local/urban road need essential maintenance within the next year. In particular, the report showed that London roads are the worst in England with almost a quarter in poor condition – twice as bad as the best roads in the country.

What is missing in the debate about funding road maintenance however, is the recognition that heavy lorries cause far more damage to foundations and structures of roads than cars. Yet they are only cover 11 per cent of their road infrastructure costs, despite what the Freight Transport Association claims. The standard 44 tonne HGV, which is the industry workhorse, causes 136,000 times more damage to road infrastructure than a Ford Focus because the damaging power rises exponentially as weight increases – a phenomenon known as the ‘Generalised Fourth Power Law’. 

Local and urban roads, unlike motorways, are not built to sustain the large volume of heavy goods now traffic using them. And yet, the Road Haulage Association complains that its lorries are being damaged by the existing poor state of local roads – a phenomenon, for which they are largely responsible.

Consider a report called Heavy Goods Vehicles: Do they pay their way? – impacts on road surfaces, produced by RepGraph for the Freight Trade Association (FTA). It claimed HGVs pay three times more than their estimated damage costs to infrastructure. But our analysis at the Campaign for Better Transport shows that the FTA-commissioned RepGraph report is based on out-of-date figures and incorrect assumptions. In fact HGVs only cover one ninth of their road damage costs.

The wider problem is that this underpayment by lorries is not confined to road maintenance. In fact our latest report, which uses government values, shows that HGVs are still only paying a third of the costs they impose on the economy and society in terms of road congestion, road crashes, road damage and pollution costs. HGVs are almost seven times more likely than cars to be involved in fatal collisions on minor roads. They’re responsible for 17 per cent of greenhouse gas emissions and a fifth (21 per cent) of NOx emissions from road transport, despite making up just 5 per cent of vehicle miles. When the full costs of HGVs are taken into account that equates to a £6bn a year taxpayer subsidy.

This subsidy undermines the incentive for the haulage industry to be efficient. Only a third (34 per cent) of HGVs are full in terms of load volume. Almost another third (30 per cent) are driving around completely empty – a figure that’s been growing for some years. Partially loaded trucks result in unnecessary lorry journeys to feed our shopping habits.

In contrast, the German distance-based charging system incentivises efficiency and has reduced empty lorries by a third, as well as reducing tonne kilometres because of better loading rates; prior to its introduction, Germany had similar empty lorry levels to the UK. In Austria, per km charging for trucks reduced the percentage of empty vehicles from 21 per cent to 16 per cent. Average loads grew by 0.6 tonnes, to 14,7 tonnes, between 1999 and 2004.          

That’s why we are calling on the government to introduce distance-based charging in its current review of the Lorry Road User Levy. This would better reflect HGV’s costs, encourage the use of less polluting lorries, and reduce unnecessary lorry miles by making more efficient use of the road network.

It is the duty of the government to make sure that the adverse impacts of road freight transport on the economy, the environment and society are minimised and that the public purse is not subsidising bad practice.

Philippa Edmunds is freight-on-rail manager at the Campaign for Better Transport.

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