Lower Thames Crossing

Lower Thames Crossing
Name	Lower Thames Crossing
Location	Thurrock, Essex; Gravesham, Kent; Dartford Crossing vicinity
Status	Under construction / planning (as of 2024)
Owner	National Highways
Type	Road tunnel and approach roads
Length	~14.3 km (route corridor)
Lanes	4–6 lanes planned

Lower Thames Crossing The Lower Thames Crossing is a major road transport project to provide a new road tunnel under the River Thames linking the M25 motorway corridor east of Dartford Crossing between Thurrock in Essex and Gravesham in Kent. Promoted by National Highways and shaped by ministers in the Department for Transport, the scheme aims to relieve congestion on the Dartford Crossing, improve connectivity for London and the southeast, and support freight movements to Port of Tilbury and Port of London.

Overview

The project comprises a twin-bore bored tunnel beneath the River Thames with approach roads, river crossings, junction improvements and new road bridges near the A13, A2 road, and M2 motorway corridors. It is envisaged as part of a strategic route between the M25 motorway and southern routes toward the Channel Tunnel via the M20 motorway and southeastern ports. Proponents including National Highways, ministers such as those in the Department for Transport, and local authorities like Thurrock Council and Gravesham Borough Council have defined objectives around capacity, resilience and economic development for the southeast of England.

History and planning

Proposals for an additional Thames crossing east of Dartford date back decades and have been considered alongside schemes such as the M25 and earlier Dartford Tunnel proposals. Significant milestones include studies by the then Highways Agency and public consultations in the 2000s and 2010s, followed by the 2017 recommendation of a preferred route near East Tilbury and Shorne Woods. The project entered development consent processes under the Planning Act 2008 regime, involving examinations by the Planning Inspectorate and decisions by successive Secretaries of State for Transport. Environmental Impact Assessments involved agencies like Natural England and Environment Agency.

Route and design

The chosen alignment features a twin-bore tunnel approximately 2–4 miles beneath the River Thames with portals on the north bank near East Tilbury and the south bank near Shorne Common. Surface approaches connect to the A13 to the north and to the A2 and M2 to the south, with new junctions and upgrades to existing corridors. Design elements include multiple lanes in each bore, dedicated freight provisions, emergency cross passages, tunnel ventilation and control systems overseen by firms such as National Highways and private sector contractors. Engineering considerations have involved geotechnical work in the Thames Estuary and mitigation for chalk and riverine substrates.

Environmental and community impact

Environmental assessment considered effects on habitats including RSPB-concerned wetlands, Epping Forest-linked ecosystems, local Sites of Special Scientific Interest (SSSIs), and designated Green Belt land. Community impacts encompass potential changes to Tilbury and Gravesend commuter patterns, local air quality monitored against Air Quality Standards Regulations 2010 benchmarks, and noise mitigation near residential areas such as Shorne and West Tilbury. Mitigation strategies and compensation measures have been discussed with bodies including Natural England, local parish councils and Historic England where heritage assets are affected.

Construction and cost

Construction procurement has involved frameworks and competitive bidding by major contractors and consortia that have previously worked on projects like Crossrail, Thames Tideway Tunnel, and M25 widening schemes. Cost estimates have evolved, with reported budgets taking account of tunnelling, land acquisition, construction of approach roads, environmental mitigation and utility diversion. Funding arrangements contemplate central allocations from the Treasury and delivery overseen by National Highways, with contractor models ranging from design–build to design, build and operate. Programme timelines have been influenced by supply chain capacity, planning delays, and comparators such as the delivery experience of High Speed 1 and other large infrastructure works.

Traffic, tolling and operations

Operational planning addresses capacity modelling informed by traffic studies linking the M25, A13, A2 and M2, and forecasts for freight movements to the Port of Tilbury and cross-Channel routes. Authorities have considered tolling arrangements similar to those on the Dartford Crossing to manage demand and fund operations, with consultations involving Freight Transport Association stakeholders and local elected representatives. Day-to-day tunnel operations will involve traffic management, incident response coordinated with the National Police Chiefs' Council for major incidents, and maintenance regimes comparable to other tolled river tunnels.

Controversy and legal challenges

The project has attracted opposition from local campaign groups, environmental organizations and some local authorities citing impacts on Green Belt designations, air quality, biodiversity loss, and landscape character. Legal challenges and judicial review applications have engaged the High Court and procedural scrutiny under the Planning Act 2008 examination processes. Debates have referenced previous contested schemes such as the Tideway approvals and planning controversies over projects like Heathrow expansion, highlighting tensions between national connectivity objectives and local conservation priorities.

Category:Road tunnels in England Category:Transport in Essex Category:Transport in Kent