Kent businesses are being urged to make their views known on the future management of the Dartford Crossing.

The call has gone out in a survey launched by the Federation of Small Businesses (FSB).

The Department for Transport is currently running a consultation on the future management of the Dartford Crossing including proposing higher charges, a possible new crossing between Essex and Kent and using number plate recognition toll collection systems.

Roger House, chairman of the FSB's Kent and Medway region, says he wants all Kent bosses to respond, not just those who run small businesses.

The survey follows last month's announcement that the government plans to raise the fee for a single car journey from £1.50 to £2 this year and to £2.50 in 2012.

Consultation on the proposed fees has opened and the government was keen to stress a new trial came into effect for six months from July 1, where the Highways Agency, which manages the crossing, is given the power to lift the tolls in severe congestion.

But it has now emerged just what severe congestion means - 9.3 miles in Kent and 11 miles on the Essex side of the crossing.

While any lifting of the tolls would be considered on a case-by-case basis, guidance given to the Highways Agency by the Department for Transport suggests there has to be an emergency situation "where continuous queues extend back, or have the potential to extend back, to junction 4 of the M25 [Orpington] or junction 28 [Romford], or beyond."

The charges were last suspended in March when two riders came off their bike inside the tunnel. It was only the fifth time in as many years the tolls were lifted. One of those times was in August when the Queen Elizabeth II Bridge was closed for more than three hours after a lorry caught fire and the Dartford Tunnel was used for all traffic.

The consultation is open until September 23. See www.dft.gov.uk

Any decision to suspend the Dartford tolls would be made by the Highways Agency's regional manager and regional operations director, based on guidance from staff at the crossing.

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