The Herrenknecht Mixshield TBM built in Schwanau, Germany for National Grid’s Grain to Tilbury project has arrived in Tilbury, UK—marking the transition from factory readiness to site delivery for one of the UK’s most challenging power-tunnel drives. 

A logistics operation as complex as the tunnelling -  Moving a large-diameter TBM is never a simple “delivery”—and this one was a full multi-mode operation.

TBM main components by sea: the cutting wheel, shield, thrust unit were shipped in sections due to their exceptional size and weight, travelling from Kehl harbour in Germany via Antwerp before reaching Tilbury Port.

Gantry systems by road + ferry: the gantries were transported by truck from Germany to Rotterdam, then loaded onto a ferry for direct delivery to the construction site. 

Heavy-lift highlights: with around 100 tonnes, the thrust unit was among the heaviest individual items transported. 

(The routing and component-by-component shipping details above reflect the project delivery update you provided; the sources below focus on the project scope, contractors, and tunnelling conditions.) 

Why Mixshield for Grain–Tilbury? 

The Grain to Tilbury scheme will replace the ageing Thames Cable Tunnel beneath the River Thames between Tilbury and Gravesend—an asset dating back to the late 1960s and carrying 400 kV transmission circuits. 

The new drive is 2.2 km long beneath the Thames, and is expected to encounter “difficult ground” characteristics typical of river crossings: hard, abrasive materials and high groundwater pressures. National Grid and industry reporting highlight conditions including very strong flintstone, high permeability, and water pressures up to 4.5 bar—exactly the kind of environment where slurry / Mixshield technology is selected to control face pressure and manage inflows. 

Project scope: power resilience under the Thames 

National Grid describes Grain to Tilbury as a critical reinforcement to keep reliable, lower-carbon electricity flowing across the South East, delivered as part of The Great Grid Upgrade. 

Public planning documentation summarises the tunnel’s purpose clearly: a new 2.2 km tunnel under the Thames designed to carry 12 new high-voltage cables, replacing the existing tunnelled section of the Tilbury–Grain / Tilbury–Kingsnorth 400 kV circuits.

Delivery team and programme 

The tunnelling works are being delivered by the Ferrovial Construction and BEMO Tunnelling joint venture. BEMO has stated the contract value at £230m, with works commencing in early 2025 and a planned completion in Q1 2029. 

What happens next on site?

With delivery complete, attention shifts to the practical realities of getting a TBM into the ground: 

Reassembly at the launch shaft (the TBM was designed to be dismantled for transport and rebuilt on site). 

Shaft and site-readiness works to enable safe launch, logistics, and continuous tunnelling operations. National Grid notes enabling works and shaft activity underway as the project moves into construction. 

The Thames drive: a controlled, pressure-balanced excavation beneath a major tidal river crossing—where geology, groundwater, and wear management will define performance. 

Contract Award & Tender Summary

Public Procurement Notice

An official tender award notice was published on the UK Government’s Find a Tender Service:

• Notice Title: Grain - Tilbury Project (TKRE)
• Awarded by: National Grid Electricity Transmission PLC
• Notice ID: 2025/S 000-001754
• Published: 17 January 2025
• Procurement type: Works contract (Design and build)

Scope of Procurement

According to the tender notice, the contract includes:
Design and build of a new tunnel for high voltage (HV) cables under the River Thames
Design, supply and installation of a 400 kV cable system
Design and build of headhouses and associated Mechanical & Electrical (M&E) works
Design and build of a cable sealing end compound (SEC)
Electrical, mechanical and civil engineering elements as part of the tunnelling and above-ground infrastructure

Procedure & Timeline

• The procedure was a negotiated procedure with a prior call for competition, meaning National Grid invited select bidders to tender before final award.
• Contract concluded: 18 December 2024.

Contract Value & Contractor

Awarded Contractor

• The contract was awarded to an integrated joint venture:
  Ferrovial Construction & BEMO Tunnelling (trading as Ferrovial BEMO JV)

Contract Value

• Approximate value: £230 million (design & build tunnelling contract)

Contract Duration

• Construction expected to run from early 2025 to Q1 2029.

Key Commercial and Delivery Insights

Contract Structure

The contract includes both subsurface tunnelling works and above-ground electrical/terminating infrastructure:

• Deep excavation (tunnel + shafts)
• 400 kV cable installation
• Headhouse construction
• SECs (Cable Sealing End compounds)
  This means the award was not just a TBM contract but a multi-discipline design & build EPC style contract.

Delivery Team

• Ferrovial Construction – lead contractor for construction and tunnelling works.
• BEMO Tunnelling UK – tunnelling specialist partner delivering TBM operations and underground engineering.

 Where to Access Tender Documents

You can view the public procurement notice and associated documentation via the UK Government’s Find a Tender Service:

Grain – Tilbury Project (TKRE) – Award notice:
https://www.find-tender.service.gov.uk/Notice/001754-2025/PDF For further information about the project click here.  08/26.