What is the Lower Thames Crossing?

Closed 20 Dec 2018

Opened 10 Oct 2018


The Lower Thames Crossing is a proposed new motorway connecting Kent, Thurrock and Essex through a tunnel beneath the River Thames. It will provide much needed new road capacity across the river east of London.

On the south side of the Thames, the new road will link the tunnel to the A2 and M2 in Kent. On the north side, it will link to the A13 and junction 29 of the M25 in the London Borough of Havering. The crossing and the new connecting road network will provide quicker and more reliable journeys locally, regionally and nationally.

This is the most ambitious project of its kind in the country. It is the largest single road investment project in the UK since the M25 was completed more than 30 years ago. The crossing under the Thames will be the longest road tunnel in the country. At 16 metres in diameter, it will be one of the largest bored tunnels in the world.

The Lower Thames Crossing will have:

  • approximately 14.5 miles (23km) of new roads connecting the tunnel to the existing road network
  • three lanes in both directions with a maximum speed limit of 70mph
  • improvements to the M25, A2 and A13, where the Lower Thames Crossing connects to these roads
  • new structures and changes to existing ones (including bridges, buildings, tunnel entrances, viaducts and utilities such as electricity pylons) along the length of the new road
  • two 2.5 mile (4km) tunnels, one for southbound traffic, one for northbound traffic crossing beneath the river
  • a free-flow charging system, where drivers do not need to stop but pay remotely, similar to that at the Dartford Crossing

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The crossing will form a vital new part of the UK’s transport infrastructure, transforming the regional and national road network. Building a reliable, modern new road that is fit for the future will help businesses to grow, and bring people and communities closer to jobs, education and leisure opportunities.

The new crossing will support businesses, large and small


With a project of this size and scale, we must get all aspects of the design, construction and operation right. We can only do this by working with you and by listening to your views and concerns.

Did you know? The Lower Thames Crossing will be around 7 miles from the Dartford Crossing.

So far we have been working closely with residents, community groups, businesses, local authorities, regulators and other organisations to develop our designs. Now it is your opportunity to shape the Lower Thames Crossing before we apply for a Development Consent Order (DCO), which would give us the planning consent we need to start construction.

Continue to the next section: Section 3: The story so far

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