On This Day

Friday 7th June 1991

29 years ago

Construction of the road Dartford - Thurrock River Crossing over the Thames was completed. It consists of two bored tunnels and the Queen Elizabeth II Bridge, a cable stayed bridge. The only fixed road crossing of the Thames east of Greater London, it is the busiest estuarial crossing in the United Kingdom, with an average daily use of over 130,000 vehicles. The crossing's development started in the late 1930s, but was interrupted due to the Second World War and resumed in the 1950s. The original tunnel catered for a single lane of traffic in each direction, but rising traffic levels required the second tunnel to be built. It opened in stages: the west tunnel in 1963, the east tunnel in 1980 and the bridge in 1991. The M25 connected to the tunnels at both ends when completed in 1986, and this increased traffic put pressure on the tunnels' capacity. A Private Finance Initiative scheme was started in 1988 to build the bridge. The combined crossing now handles four lanes of traffic in each direction. The crossing forms part of the M25 motorway's route, though it is not under motorway restrictions itself. It has been described as one of the most important road crossings in Britain, and suffers from heavy traffic and congestion. When it was opened, the bridge was Europe’s largest cable-supported bridge. The central span is 450 m (1,476 ft) long and is suspended 65 m (213 ft) above the Thames (to accommodate ocean-going cruise liners). The approach viaducts on the Essex side measure 1,052 m (3,451 ft) and 1,008 m (3,307 ft) on the Kent side, giving a total length of 2,872 m (9,423 ft). It has an expected life span of 120 years. The toll bridge accommodates four lanes of southbound traffic from the M25. When closed, due to high winds for example, one of the two adjacent tunnels are used instead.