The Lower Thames Crossing route
The longest road tunnel in the UK
The Lower Thames Crossing would be the longest road tunnel in the UK, stretching 2.6 miles
14.3 miles of new road
The route would include 14.3 miles of new road connecting the M2/A2, A13 and M25
New bridges and viaducts
Around 50 new bridges and viaducts would be built
Route developments
On the south side of the River Thames, the new road would link to the A2 and M2 in Kent. On the north side, it would link to the A13 in Thurrock and the M25 in Havering.
The tunnel crossing would be located to the east of Gravesend on the south side of the river, and to the west of East Tilbury on the north side.
The tunnel would be made up of two 2.6 mile (4.3km) tunnels crossing beneath the river, one for southbound traffic, one for northbound traffic.
The tunnel
The tunnel is comprised of two 2.6 mile (4km) tunnels, one for southbound traffic, one for northbound traffic crossing beneath the river, it will be over 16 metres in diameter – amongst the widest in Europe.
It will pass beneath the River Thames with its southern entrance located to the east of the village of Chalk, and its northern entrance to the west of East Tilbury. On the northern section, the tunnel will pass under the East Tilbury Marshes.
The following image shows the proposed Thong Lane green bridge linking Gravesend and Thong and the approach to the southern tunnel entrance, looking north (Design refinement consultation 2020)
The route - South
The A2 will remain as four lanes in both directions with hard shoulders throughout. The M2 will be widened from three lanes to four in both directions through junction 1.
Two one-way link roads will be provided north and south of the A2, connecting to the existing A289 and the old A2 at the eastern end. Neither of these link roads will connect to the A2 at M2 junction 1, with these connections being made at the site of the new LTC junction instead.
The A2 will be kept at its existing height and the link roads will be at approximately the same height.
We will need to rebuild a section of the M2/A2 immediately to the west of the new junction and for approximately 2 miles (3.5km) to the east, including junction 1 of the M2.
The route will pass under Thong Lane and approach a new junction with the A2, situated at the eastern edge of Gravesend. The road will be in a cutting approaching the tunnel.
The following image shows the proposed M2/A2 along the A2 near Park Pale bridge, looking west (Design refinement consultation 2020)
The route - North
The route north of the river from the crossing passes by Tilbury, Chadwell St Mary, Linford, Orsett and Ockendon.
The image shows the proposed northern tunnel entrance approach, looking south (Design refinement consultation 2020)
A13 junction
The route continues passing by West Tilbury, Linford and Chadwell St Mary to approach a new junction layout between the Lower Thames Crossing, A13 and A1089. It will be located at the site of the existing junction between these roads to the west of Orsett.
The new route will pass under the A13 to the east of the existing A1089 bridge. The existing connections between the A13 and A1089 will all be retained with some modifications. A short section of the new route will reduce to two lanes in both directions around the A13 junction.
Beyond the A13 junction the route would continue north west of Orsett turning further west.
LTC/M25 junction
The route would continue across the Mardyke river and Golden Bridge Sewer. It would then connect with the M25. The junction with the M25 will be located just under two miles (3km) south of junction 29 on the M25, near Ockendon Road.
The junction will have slip roads for northbound LTC traffic to join the M25 and southbound M25 traffic to join the LTC.
A short section of the M25 will be reduced from four lanes to three lanes.
Improvement work will also be carried out on the M25 between the new junction and junction 29.
M25 junction 29
Beyond the northern section of the Lower Thames Crossing, improvement and modification works will also be needed at junction 29 on the M25 and to the north of junction 29.
The M25 through junction 29 will be widened from three lanes to four in both directions with hard shoulders.
The connections of the north-facing slip roads at this junction will be changed because of the widening through the junction. Changes will also be carried out at the existing junction 29 roundabout.
