Progress is being made with regard to the proposed Lower Thames Crossing project close to London. The project will include driving a new road tunnel, the UK’s longest, as well as building new dual carriageway connections to the existing network.
The aim of the project is to reduce the chronic congestion that occurs at the Dartford Crossing and Blackwall Tunnel at peak periods at present. This new route would virtually double the traffic capacity between Kent and Essex, helping reduce congestion on the existing routes, which handle a high percentage of heavy vehicles using the port of Dover as well as the Channel Tunnel.
According to Highways England, the multi-billion pound project is set to be the most ambitious road project since the M25 opened 30 years ago. The area to the east of London carries amongst the heaviest traffic volumes in Western Europe due to the proximity to London, Western Europe’s most populous city, and the busy port of Dover.
The improved proposals include making the whole route a three-lane dual carriageway to improve traffic-flow; a new design for the Tilbury junction, removing the proposed Tilbury link road to reduce traffic on the local road network, and; an improved junction with the A2.
The 23km route connecting Gravesham in Kent and Thurrock in Essex is expected to reduce traffic at Dartford by 22%t with 14 million fewer vehicles using it every year. It will almost halve the morning peak average journey times between M25 junctions 1b and 31 from nine minutes to just five
The project will create a new, three-lane dual carriageway connecting the M2 near Rochester and the M25 in Essex between North and South Ockenden. It would include a 3.84km-long tunnel under the Thames between Gravesend and Tilbury – the longest road tunnel in the UK – and, at over 15m-wide, the third largest bored tunnel in the world.
No details have been released as to the TBM that will be used to drive the tunnel but the ground conditions in the area are very suitable for this type of excavation.
The plans include an updated, more detailed design which aims to maximise the project’s huge benefits and includes significant changes to minimise the impact on local communities and the environment.
Numerous measures have also been included to reduce the impact that the new road will have on local communities. The tunnel has been extended so that the entrance in Kent is 600m further south to reduce the visual impact and protect access to a community church. The road has been lowered by 5-6m in places to reduce its visual impact. The road alignment has been moved by 80m further east where is passes Chadwell St Mary to increase the distance from residential properties.
The move to construct a tunnel connection represents something of a step ahead for South East England’s transport network as a whole. However, the project has been hugely controversial due to concerns over the disturbance from its construction, traffic volumes and environmentally sensitive areas along the route of the new road link.
The Lower Thames Crossing has been discussed for many years, with numerous proposals having been put forward and then halted. As far back as 1990 a dual box girder bridge was proposed. The low-level bridge design had been considered as it would not pose a hazard to aircraft using Docklands City Airport, while offering sufficient height to allow large vessels to pass underneath. However, this design was then criticised heavily for its poor aesthetics by Prince Charles, who described it as an ugly and cheap carbuncle.