Lower Thames Tunnel
 Rail and Road links
 Tidal power generation
Flood defence for London

Tunnel location between Essex and Kent

PROJECT

An immersed tube tunnel with rail (T2), road (D3) and utility links between Essex (Canvey Island) and Kent (Hoo Peninsula), integrated with tidal power and flood defence systems:

Location / Route:

Metrotidal Tunnel links existing radial transport routes north and south of the river to form new orbitals serving the Thames Gateway Region and new north-south arteries for the Greater Southeast. The eastern limbs of Crossrail north and south of the river are linked to form a Crossrail Plus orbital service. Other rail lines are united to provide a new service between Ebbsfleet and Stansted. The A2/M2/A228 across the Hoo Peninsula is connected to the A130, A13 and A127 in Essex providing new circulation for the Thames Gateway and a trunk route between the M20/M2 and M11/A120 via Maidstone and Chelmsford.

Tunnel :

The immersed tube tunnel sections are cast locally and floated into position with a shallow gradient to allow for heavy rail freight. The sections carry T2 rail connections and a D3 highway along with emergency access, maintenance and utility wayleaves. The transport corridor extends across the marshes within an embankment to form part of the flood bund and tidal pool impoundment system.

Tidal power and pump storage:

The impounded area of the flood storage system provides a tidal pool for generating carbon-free electricity, with output enhanced by the use of wind-power pumped storage.

Flood storage:

Existing and new flood storage areas on both sides of the estuary will be co-ordinated with new gates and sluices to provide a controlled impoundment system for managing the agreed flood datum in accordance with TE2100 forecasts.

Metrotidal system diagram - tunnel (dotted), road (green), rail (black), tidal pool (blue)

Core components: