Thirty-six per cent of approved schemes have no assessment of predicted traffic levels and one-third detail their impact on accident levels, the statistics reveal. Data on carbon emissions exists for less than half of the schemes.
The figures emerged in parliamentary answers to questions by Liberal Democrat shadow transport secretary Tom Brake. He warned that road building is a self-perpetuating fallacy.
"Labour gives the green light to road projects without regard to accidents, emissions or future traffic levels," claimed Brake. "This is neither an integrated nor a joined-up transport policy."
Last week transport secretary Alistair Darling renewed his vow to cut congestion. Speaking to the Institute for Public Policy Research, he said that funding bids to investigate road pricing and other demand management ideas have been submitted by 30 local authorities. The government will pick the best to pilot the scheme, he explained.
Technology such as satellite positioning could be used in the pilot, added Darling. He emphasised that road pricing has not yet been accepted by the public, but warned that the UK cannot build its way out of congestion.
"The government is ready and able to invest in complementary public transport and travel information schemes," he added.