A large road tunnel under the Thames to the east of London has been given funding in the 2020 budget. The Lower Thames Crossing aims to link Kent with Essex out past the existing Dartford Crossing.
The crossing itself is projected to cost £6.8 billion, but investment in local roads is also likely to be necessary to deal with the predicted increases in traffic once the crossing opens. In the budget’s Red Book, the government said that it would allocate a total of £27 billion between now and 2025 to fund road upgrades, including ” building the Lower Thames Crossing to increase road capacity across
the Thames east of London by 90%”
The key elements of the Lower Thames Crossing will be two new tunnels under the Thames, and then surface roads to link up with the A2 on the south side and the A1089 and M25 to the north.
The new tunnel would be the longest road tunnel in the UK – and at over 50ft (15m) wide should be the third-largest bored tunnel in the world.
Although a road crossing of some type has been considered since 1989, it’s only in the past decade or so that consultations have finessed the plans to the current completed state. In July 2019, Highways England said they expected to submit a planning application in Summer 2020 and has a target for road opening of 2027-28.
In addition to reducing congestion — or increasing it depending on your point of view about such things — the new tunnel is expected to improve travel speeds across the Dartford Crossing, and as it’s in a tunnel, be immune from the wind-speed problems that can see the bridge at Dartford occasionally closed to traffic.