The first engineering work to take place was a compressed air driven pilot tunnel, which was drilled between and Work on the tunnel was delayed due to World War II, and resumed in , using a Greathead Shield, similar to the work on the Blackwall Tunnel some 60 years earlier.
The delay in work due to the war allowed the tunnel's design to be improved, which included a better ventilation system. After negotiations with the Ministry of Transport, Kent and Essex County Councils successfully levied a toll on the tunnel before it opened in The toll was originally two shillings and sixpence , equivalent to By , the toll for cars had risen to 60p. The first tunnel was expected to carry two million vehicles a year but by was carrying over eight million.
That year, Michael Heseltine , then a junior transport minister, announced that a second tunnel would be built in conjunction with the North Orbital Road, later to become the M Construction was approved in April , with an initial expected opening date in Work was delayed due to a lack of funds, which was resolved by EEC funding granted in The second tunnel opened in May , allowing each tunnel to handle one direction of traffic, by which time the joint capacity of the two tunnels had increased to 65, vehicles per day.
Connection of the crossing to the M25 was completed on the northerly Essex side in September Junction 31 , and to the southerly Kent side in September Junction 1a. Following the completion of the M25 in , the daily demand had grown to 79, vehicles. During the early s, it was anticipated that traffic through the tunnel would rise on the completion of the M25 in In , the Transport Minister, Lynda Chalker, announced that the number of toll booths would be increased to 12 each way, but concern grew that two tunnels would not be able to cope with the full demands of a completed M At the time there were several other privately financed projects planned or under construction in the UK, including the Second Severn Crossing.
From until the establishment of the Private Finance Initiatives PFIs in the late s, private investment projects were governed by the Ryrie Rules which dictated that "any privately-financed solution must be shown to be more cost-effective than a publicly-financed alternative, and that privately-financed expenditure by nationalised industries could not be additional to public expenditure provision, which would be reduced by the amount of private financed borrowed.
The private company was at risk of not recuperating their costs, but ultimately the Dartford scheme demonstrated that the Ryrie Rules were no longer a barrier to the private financing of public infrastructure projects. The concession was scheduled for 20 years from the transfer date, with a stipulation that it could end when debts had been paid off, which was agreed to have been achieved on 31 March Construction of bridge started immediately after the creation of the PFI in It was designed by German civil engineer Hellmut Homberg [de] , and the two main caissons supporting the bridge piers were constructed in the Netherlands.
Each caisson was designed to withstand a bridge strike of a ship weighing up to 65, tonnes and travelling up to During construction of the approach road, a World War II bomb was found in its path, which required closure of the entire crossing.
The proposed name had been simply the Dartford Bridge, but Thurrock residents objected and suggested the Tilbury Bridge, leading to a compromise. At the time of opening, it had the longest cable-stayed span of any bridge in Europe. It is the only bridge across the Thames downstream of Central London to be opened since Tower Bridge in In , the European Union issued a directive that value-added tax should be charged on all road tolls, including the Dartford Crossing. The Government opposed the directive and said it would bear the additional cost.
It was anticipated that the tolls would be removed on 1 April under the original PFI scheme contract. However, the Highways Agency decided that the tolls would become a "charge", under legislation introduced by the Transport Act to introduce charging schemes on any trunk road bridge or tunnel at least metres 2, ft in length. Under the Transport Act, the A Trunk Road Dartford-Thurrock Crossing charging scheme Order allowed the continuation of the crossing fee, which officially became a charge and not a toll on 1 April As well as maintaining the crossing, the contract required the company to widen around 40 miles of the M25 and to refurbish a tunnel on the A1 M at Hatfield.
In October , the Government announced its intention to sell the crossing as part of a public sector deficit reduction strategy. UK We use some essential cookies to make this website work. Accept additional cookies Reject additional cookies View cookies. Hide this message. From: Highways England Published 29 October Andy Dean, Chief Executive Connect Plus, said: With over , vehicles making the crossing every day, it is vital that we keep the bridge and tunnels flowing smoothly.
Mark Bottomley, Lower Thames Crossing Programme Director, said: The Dartford Crossing is a feat of engineering that has played a crucial role in almost every aspect of our daily lives, from delivering essential goods to our shelves and our doorsteps, to visiting friends and family or getting to work.
From these, the road deck is suspended by cables. Each patrol vehicle travels at an average of 40, miles per annum within the concession area. Media enquiries Journalists should contact the National Highways press office on and use the menu to speak to the most appropriate press officer.
Share this page Share on Facebook Share on Twitter. Is this page useful? Maybe Yes this page is useful No this page is not useful. Thank you for your feedback. Report a problem with this page. What were you doing? The Dartford crossing has made it much easier for vehicles in the area to get across the Thames.
The nearest alternatives to Dartford are the Blackwall tunnel about 8 miles west or the Woolwich ferry about 10 miles west. High vehicles have even less choice than cars and small lorries. When the bridge is closed vehicles over 5m high are diverted round the M25 in the opposite direction. The Dartford crossing has made the movement of goods and people easier in the area and contributed to the local economy. Engineers started work on the west tunnel in but construction stopped with the outbreak of World War 2.
Digging restarted in with the project team using a tunneling shield to excavate the tunnel. A tunneling shield is a large circular steel frame with pockets. Each pocket had a man with a spade who dug out the earth in front of him.
Work was delayed on the east tunnel through lack of money until when the European Economic Community now the EU provided cash for the project. The 2. The bridge's deck roadway hangs from 56 pairs of cables strung from the masts. The project team used 2 reinforced concrete caissons to support the river piers.
The caissons - prefabricated concrete structures — were built in the Netherlands and towed across the North Sea to the construction site. Engineers sank the 85, tonne caissons into place and filled them with concrete as part of the bridge's permanent structure. The Dartford crossing is a crucial part of the country's strategic road network. Motorist groups argue that there shouldn't be a charge for the Dartford crossing at all as the infrastructure was paid for years ago.
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Connected communities Enables thousands of people to cross the Thames in the east. Economy boosted Local economy has benefited.
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