A month after the 1997 election John Prescott memorably declared that he would have failed if, in five years’ time, there were not “many more people using public transport and far fewer journeys by car”. He has failed — and by a wide margin. The latest Transport Department figures show that, since Labour came to power, traffic has increased by 30 billion miles (11 per cent rise) and there are 4.5 million more private cars. Four years ago the Government abandoned its target of reducing road congestion by 6 per cent by 2010 and now predicts that it will rise by up to 20 per cent. And whereas in 1999 the road-building budget had fallen to £500 million (half what the Conservatives spent in their final year in power), this year it is running at more than £1 billion, a sum expected to rise steadily in the next few years.

The cost of taking a decade to realise the need for more road capacity is high. Opinion polls find regularly that transport is considered Labour’s greatest domestic failure. And road-building is as controversial as it is expensive. Environmentalists have challenged all but the most urgent plans for bypasses and new roads. Yet motorists blame the Government for the rising congestion, which has slowed average speeds on motorways and trunk roads during the evening rush from 55mph in 1995 to 51mph in 2003.

The Transport Department has therefore concentrated on squeezing more capacity out of Britain’s already overburdened trunk network. Most of the 71 schemes in the current programme involve adding a fourth lane to motorways or turning a single carriageway A-road into a dual carriageway. But an extra lane of motorway costs, on average, £25 million a mile. And so in two weeks the Government will unveil a far cheaper alternative: allowing drivers to use motorway hard shoulders during peak hours.

The proposal is controversial. Britain’s motorways are among the safest in Europe because, unlike those in many countries, all were built with hard shoulders in case of breakdown or emergency. Instead of hard shoulders, there will be only new lay-bys, known as “emergency refuges” every 500 metres. Gantries will have to be built with cameras to monitor the entire motorway, directing traffic on to the shoulder in peak periods and back off it in case of breakdowns. When the shoulders are used, traffic in all lanes will be slowed to a maximum of 50mph. But with no free lane down the side, emergency vehicles will find it hard to reach an accident quickly.

The safety issues must be resolved satisfactorily, or the good record of motorways will be compromised. But the Government is, for once, determined to move fast. The first stretch of motorway to use the shoulders will be the M42, near Birmingham; others will follow as soon as the infrastructure can be modified.

All this may prove only a palliative, however. Traffic is still rising inexorably, especially on motorways, where it will increase by up to 50 per cent over the next nine years. The Government must, at some point, grasp the issue of tolls, peak-hour congestion-charging and lanes reserved for car-pooling. Clearly, with bus fares rising twice as fast as motoring and train fares among the most expensive in Europe, any roads policy based on exhorting a switch to public transport will fall on deaf ears. The M42 experiment may be a sensible and timely innovation; it is not a panacea for congestion.