Bored? Not us!

11 October 2021


In April of this year, I shared the news that our expert team had conquered another feat of engineering at Hinkley Point C - successfully completing the 38,000 nuclear grade concrete segments required to line the three essential, underground tunnels at the new nuclear power station.

Today, we’re celebrating a further two major milestones on our Tunnelling and Marine Project.

Emmeline, one of our three Tunnel Boring Machines named after Lady Emmeline Pethick-Lawrence, a prominent Bristolian women’s rights activist, has touched the finish line, pushing through challenging ground conditions, 24 metres below the Bristol Channel, to complete the Outfall Tunnel.

Concluding her 1.8km journey, Emmeline excavated 100,000 tonnes of material – taking us one step closer to completing an essential part of the water-cooling system at the UK’s landmark nuclear power station; a system that will perform a critical role and help to cool the nuclear power station.

As one of the largest systems of its type in the world, every single permanent ring, of which there are 1,206, had to be installed to exacting standards – with every ring made up of over 9,600 nuclear grade concrete segments.

In a world first, the vast number of segments have all been constructed to millimetre precision at our purpose-built, state-of-the-art facility at our site in Avonmouth.

Forming one of the three underground marine tunnels, the Outfall Tunnel will eventually be connected to the seabed by vertical shafts and capped with large Intake and Outfall Heads, which have incidentally also been built at Avonmouth; the largest of which weighs close to 5,000 tonnes.

Once complete, these tunnels will allow 120,000 litres of sea water to flow into the water-cooling system every second.

But I said that we have achieved two major milestones, and that’s exactly what we’ve done.

Behind the scenes and alongside our partners, Rambiz and Gulliver, our two heavy lift vessels, successfully carried out a tandem trial lift of a 5,000-tonne weight, near Scheveningen in the Netherlands.

It will be these two heavy left vessels, both of which are bigger than a football pitch, that will lift the six Head structures next year into place on the bottom of the Bristol Channel.

Another fine achievement and yet another example of how we’re ready to deliver, a ‘Head’ of time - it’s clearly all ‘go’ for us at Balfour Beatty.

With a sense of achievement in the air, we’re now turning our attention to the final underground marine tunnel, with Beatrice, our Tunnel Boring Machine, reaching full bore mode this month. Once complete, the final tunnel will signify the end of our tunnelling works at Hinkley Point C; as we move forward to the next complex phase of the project.

Watch this space.