The Dartford Tunnel, now commonly known as the Dartford Crossing, was opened as a single, 2-carrigeway tunnel in 1963. It passes under the River Thames between Dartford in Kent and Thurrock in Essex. When it opened, special London Transport double-decker buses were used to transport cyclists and their bikes: bikes downstairs, cyclists upstairs. Demand from 1960s cyclists must have been quite low as the buses were faded out within a few years. A second tunnel opened in 1980, allowing separation of northbound and southbound traffic. It wasn’t until 1991, when the Queen Elizabeth II Bridge was opened, that the full flow of M25 traffic could be accommodated. The only bottle-neck remaining was that caused by the toll booths. Although the cost of construction was paid off by 2003, toll charges remain.

A report commissioned by the Highways Agency, over 12 years ago, estimated that the congestion caused by the toll booths is equivalent to 32,000 tonnes of CO2 per year. Undoubtedly that figure has since increased significantly.

From 6am on Sunday 30 November 2014 there will be no need to stop at the barriers and by April 2015 the barriers and toll booths will have been removed, potentially reducing both congestion and air pollution. Dart Charge is the new payment regime under which motorist can either pay in advance or by phone or website up until midnight on the day after crossing.

For more about the environmental impact of traffic congestion see both the Cotswold Motor Museum publications on Air Pollution and The Route to Lower Usage on our Exhibitions webpage. You can even download them if you wish.