ALTHOUGH the Government is insisting that tolling will be part of the funding mix for the A14 improvements, the Department for Transport has made no attempt to identify the detail – other than to say the arrangements will be “free flow” – nor how rat-running to avoid paying will be discouraged.

A variety of tolling arrangements exists around the world, though British drivers have little experience of free flow collection.

Even where free flow technology is used, for example the ‘Dart-tag’ for regular users of the Dartford Crossing in east London, it is deployed in conjunction with toll booths – precisely what DfT has vowed to avoid.

Technically, the A1(M) in Cambridgeshire is also tolled, but the ‘shadow tolls’ levied by the company that designed, built, financed and will operate the stretch for 25 years are paid directly by the Government. On the new A14 the tolls will be paid by the user.

A variety of vehicle recognition systems exist, based on cameras, microwave technology and so on. Some free flow packages include a variety of complementary technologies, such as a combination of automatic number plate recognition, smart tags and mobile phones.

Whatever system is deployed on the A14 – which is part of the TransEuropean Network of highways and carries one of the highest volumes of foreign-registered trucks in Britain (only the M2 and M20 come close) – will have to ensure foreign drivers pay their share.

That could involve something as simple as the Swiss system of vignettes. Drivers pay a one-off toll each year to use the country’s motorway network, in exchange for which they get a very sticky badge to put on their front windscreens.

Roadside cameras ensure that drivers of any vehicle not displaying a vignette can expect to see flashing blue lights in their wing mirrors, followed by a trip to the nearest ATM to pay for the vignette plus a substantial fine for the officers’ trouble.

But, unless the Government plans to pay for all future road improvements by tolling, such a scheme would be too crude for the A14 – making those who use the road once pay the same annual toll as those who use it four times a day.

Nor has the Government decided which part of the new road will be tolled or whether there will be a flat rate of toll or related to the distance travelled on it or the timing of journeys.

In any event, it is generally accepted that tolls would be unlikely to contribute more than around £300million to the capital cost of whatever scheme is finally decided on.

As to rat-running, the temptation to use the local roads for nothing will depend in part on the level of toll and the obstacles put in the way of through journeys.

Imposing weight limits and demolishing the viaduct at Huntingdon is likely to deter heavy through traffic, and closing some junctions will also contribute – though it will make access to and from the road more difficult for bona fide local traffic, too.

But Huntingdonshire and South Cambridgeshire villagers will certainly not countenance a constant flow of through traffic on their high streets.

Cambridgeshire County Council says it is absolutely clear that it will minimise rat-running though it cannot yet say what measures it will deploy.