Swampy, your hour will come again!

Labour inherited a declining roads budget and a consensus against building more. Now it may be sowin

When the Prime Minister's ally Gus Macdonald was installed at transport as back-seat driver, he is reputed to have said: "I've been put into this job to keep transport quiet before the election - and that's exactly what I intend to do by whatever means necessary." Those means included prematurely committing his department to 360 miles of strategic road widening, 100 bypasses and 130 local road schemes while his staff were still conducting appraisals to determine if the roads would really solve the problem.

This was a major reversal of the consensus that Labour inherited. The Donga tribes of Newbury and Twyford Down had radicalised sections of Middle England's sensible-shoe brigade in defence of countryside threatened by roads. Technical experts had established that new roads generate extra traffic and concluded that there was no firm evidence for the folklore that they inevitably brought jobs. The cash-poor Tory Treasury accordingly shrunk the roads programme and increased fuel duties to combat congestion. (As a result, traffic has continued to grow, but by lower volumes than expected.) The then shadow transport minister, Andrew Smith, drew cheers from Labour conference with his promise of "no more Twyford Downs", and when John Prescott pledged to cut the number of car journeys, even the AA and RAC were on board with the policy - albeit rather nervous about the speed and direction.

So what happened? Prescott needed new powers and more cash to invest in public transport, but Tony Blair and Gordon Brown gave him neither - the latter being eager to collect from motorists but reluctant to reinvest in transport until the course of media opinion had already begun a damaging shift. The result was Macdonald's sudden splurge of spending on roads - demanded by Downing Street advisers who were so desperate for positive media images that they inquired if any town was in need of a new and photogenic bridge.

But already, Professor Phil Goodwin, Prescott's former chief adviser and one of Europe's top technical experts, has uncovered holes in the government's £180bn ten-year transport plan that ministers promise will ease congestion. Goodwin calculates that the difference to average journey times will be so small that most drivers won't notice - with or without the investment. Inter-urban trunk road users will save one second a mile, but there will be a marginal increase in congestion on motorways and in rural areas and small towns.

A government spokesman did not deny the figures, but said it had been a substantial achievement to prevent congestion getting worse on all roads. The congestion forecasts are now being re-examined, for fear that drivers may have had their expectations of jam-free driving raised too high.

A major problem is the government's nervousness of imposing further costs on drivers. Congestion is indeed a serious problem for business, but, almost unanimously, economists have warned for 20 years that it will not be solved while motoring costs are static or falling and the economy is growing. Even before Blair's fuel price capi-tulation last autumn, civil servants forecast that drivers' costs will fall by 20 per cent over the next decade thanks to lower car purchase prices and more efficient vehicles. This may prove popular with headline-writers, but Goodwin warns that the government may have underestimated the resulting increased demand for road space by as much as 500 per cent.

His analysis of government figures shows that the biggest falls in congestion will happen in London - not from new roads, but from bus priority measures and from road pricing to be introduced by Ken Livingstone, who was elected despite the media's certainty that road charges were political suicide. (Polls show that many drivers are prepared to pay more, so long as the cash goes on cheap public transport to attract other drivers off the road.)

Ministers should also be concerned about those who do not want to see prime countryside sacrificed so that congestion can be eased. Macdonald knows that bypasses are often popular on a local level, but he promised in a letter to the Guardian that there would be a "strong presumption against greenlighting roads that would adversely affect environmentally sensitive sites". A subsequent Act of Parliament stipulates that nationally designated sites should not be breached, except in the clear national interest.

But Macdonald has since approved several road schemes through sensitive areas, and an investigation by the Today programme recently highlighted serious flaws in his department's roads appraisal process. Of the 39 local council road projects provisionally accepted by the government, nine are in some of the most valued countryside in the UK. A further 34 are still being analysed. Despite the government's stated green credentials, not one road has been rejected on environmental grounds.

In Cumbria, the government has provisionally approved a five-mile bypass round Carlisle through some of the most protected fields in Britain - splitting a Special Area of Conservation, threatening an otter breeding site and running over the World Heritage Site of Hadrian's Wall. Cumbria council asserts that the road will bring jobs for people in the moribund coastal towns of Whitehaven and Workington. But the Government Office for the North West told Today that the road might harm the coastal economy by encouraging employers to relocate next to the M6. The council leader claims not to have been given this advice, and it does not appear on the appraisal form seen by ministers. Nor does an alternative (though less convenient) route to the industrial estate that could be opened at a fraction of the cost, without damaging any wildlife sites.

In Dorset, the county council wants a bypass through the coastal Area of Outstanding Natural Beauty. Its appraisal form claims that Weymouth is in need of major regeneration, because 4,500 jobs have been lost at a navy base. But, by the time the appraisal was submitted, Weymouth had a jobless total below the national average, all the navy jobs had been substituted and the town's economy was described by the local chamber of commerce as "booming". The Government Office for the South West allowed the appraisal to stand. Some of the other controversial schemes affect Salisbury, the Blackdown Hills, the Norfolk Broads and the Peak District - but perhaps the most controversial is at Hastings, where the South East England Regional Assembly has just voted in favour of a double bypass through an intimate ancient landscape that is supposedly protected as both an Area of Outstanding Natural Beauty and a Site of Special Scientific Interest.

Almost all of the town's traffic is local and, according to a consultants' report, the summertime jams could be alleviated by a metro-style rail service on existing track. The wider issue concerns chronic social exclusion in areas of cheap, substandard housing in old Hastings, which fall into the bottom 10 per cent on the UK deprivation scale. The consultants' report concluded that the bypasses, if combined with a regeneration strategy, including a new industrial estate, could reverse the area's economic decline.

But the report raised several questions about the likelihood of achieving that goal. The real problems in Hastings, it suggested, are the lack of skills and education, and the poor road and rail links to the M25. Far from increasing jobs in the old town, the bypasses could lure employers out of it, leaving 300 fewer jobs in the most deprived areas. "There is a risk," the report said, "that the benefits will not accrue to those within the area most in need." A little arithmetic on the projections suggests this may be an understatement. The inhabitants of the new homes planned to be built next to the bypass could grab all the new jobs that might be created, leaving the area with 800 fewer jobs and generating 2,000 extra car trips every day as people commute to find work. The report does not discuss what will happen to the socially excluded if the bypass turns Hastings inside out with greenfield jobs, homes and leisure out of the reach of those without a car. Nor did it examine whether non-transport solutions could be found for the problems, at less risk to the taxpayer or environment.

Few councillors appear to be aware of the economic and social dangers of the bypass; the Hastings council leader has repeatedly rejected attempts by the BBC to question him about the risks. The latest opinion survey in Hastings showed a significant and vocal minority against the roads on purely environmental grounds, even before the economic doubts emerged. It will be left to ministers to decide if the risks are worth taking when the only certainty is the destruction of the sort of landscape they are committed to protect.

Roger Harrabin is the environment correspondent for BBC Radio 4's Today programme