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Roads go billions over budget

25 June 2009
The case for building more roads has been knocked by new research showing that the proposed roads are running over budget and that even if they go ahead, they are unlikely to solve traffic problems. 

Government figures unearthed by Campaign for Better Transport [1] reveal that the Highways Agency's road building programme is significantly over budget. These cost increases, combined with expected cutbacks in public spending [2], mean that it is highly likely that many of these schemes will not be built.

The request revealed that:


  • Three-quarters of the 16 roads which opened to the public in the last year were more expensive than expected. Overall they were 54% over budget
  • The overall programme - including those finished in the past 12 months, those under construction, and those in the planning stages - could be as much as £3.9 billion over budget  

The information coincided with a report by the Highways Agency into new bypasses [3] which found that the majority of bypasses have considerably more traffic on them than expected.


The report looked at 20 different bypasses one year after they had opened, and found that 60% of bypasses had more traffic on the new bypass and the old route than predicted; 40% of them had 25% more traffic on the old (bypassed) route than predicted. The report also found that forecasting of economic benefits are generally not accurate and that roads also tended to cost more than predicted.

Campaign for Better Transport's roads and climate campaigner, Richard George, said:

"We need to improve transport but pouring money into this black hole isn’t the way to do that. Rising costs and shrinking budgets means that some of these roads will never get built, so the Government should accept that we cannot build our way out of congestion, cancel some of these over-priced schemes and invest the money instead in decent and affordable public transport to give us an alternative to traffic jams and gridlock."



Notes to editors

[1] The Freedom of Information request revealed cost increases between programme entry (when the Government agrees to fund and build a road) through to outturn (completion) or the current best estimate as to the outturn cost (pdf 22K)

[2]As reported in the Guardian: http://www.guardian.co.uk/politics/2009/jun/07/road-safety-cycling-bus-budget-cuts

[3] The Highways Agency report, Post Opening Project Evaluation, was produced in March 2009 as a series of documents (see below). Some key findings from the Highways Agency report:


  • Over half of the scheme models have under-predicted traffic volumes on the old route and of these 12 under-predictions, eight are under-predicted by more than 25%
  • The majority of the schemes that have outturn traffic volumes [on the old, bypassed route] above those predicted are significantly above the 25% threshold, whereas those over-predicting reflect a closer fit
  • A large number of schemes (35%) show differences [in traffic levels on the new bypass] of greater than 25%, and the majority of these have outturn traffic volumes above those predicted
  • There are clear reasons why these differences occur, namely quality and scope of the modelling undertaken, which have not reflected the actual changes in traffic volumes on different roads, and the key assumptions used within forecasting
  • Forecasting of economic benefits is generally not accurate (only 38% of schemes have predicted time benefits and 29% of schemes have predicted accident benefits within 15% of the outturn)
  • Only 42% of predicted scheme costs are within 15% of the outturn, with a tendency to overspend
  • Where variances [in cost] did occur, they tended to be quite large, 38% of schemes showed variations in outturn cost of greater than 30% either above or below the predicted cost

PDFs of the documents that make up the Highways Agency report, Post Opening Project Evaluation: