Are the government's multi modal studies too heavily skewed in favour of road building?
Last week secretary of state for transport Alistair Darling blamed the consultants working up government commissioned multi modal transport studies for coming up with 'muddled' solutions.
He said they recommended too many schemes and failed to provide detail about what they would entail (NCE 7 November).
This week consultants retorted that the briefs laid down by the government had 'not been tight enough' for the information now demanded.
When the studies were first commissioned consultants were told that road building should only be an option of 'last resort'.
But the government never defined the circumstances under which a last resort option is needed, says independent consultant Denvil Coombe, who has worked on the South West Yorkshire and M25 Orbit multi modal studies.
As a result, the studies have thrown up more road schemes than the 38 which were held back pending their findings.
Public transport schemes have lost out to road schemes in the multi modal studies because many road projects have already been worked up in detail, while public transport ideas are being developed almost from scratch.
Existing cost benefit analysis of projects is also skewed heavily in favour of roads because it ignores the potential for public transport to tackle soft issues like social exclusion or health as well as congestion.
But more roads are expected to attract increasing volumes of traffic especially as motoring costs fall in line with moves to improve fuel efficiency. There is also pressure to align the cost of relatively expensive UK cars with other EU countries.
This means that, in the absence of fuel duty rises or motorway charging, new schemes will do little to ease long term congestion.
In too many cases road user charging has been completely disregarded for key stretches of motorway. In others it has been deferred until after 2020 when it will be too late to affect traffic levels, says Coombe.
The result could be a farcical patchwork of areas where road user charging is recommended next to others where it is not.
Coombe has strongly urged the government not to build new roads until it is possible to introduce demand management measures.
These would include electronic area wide road user charging schemes that can stop roads filling up with new traffic and pay for key public transport improvements.
It was ironic that last week Darling's officials told the Commons transport select committee that public transport had the potential to dramatically cut many short distance car journeys on motorways and trunk roads.
There lies the rub, claim critics. Officials now have to reconcile their recognition of the need for more public transport with the fact that the multi modal studies have generally discounted it in favour of roads. If they do not, road building will inevitably be an 'option of last resort' all over the country.