What happened

Tunnelling is complete on the fish return system at Hinkley Point C, EDF's nuclear new build project in Somerset. A tunnel boring machine named Sarah Guppy has bored a 620 metre, 1.8 metre diameter tunnel under the Bristol Channel in five months, Construction Enquirer and World Nuclear News reported this week. The machine was retrieved from the seabed by a floating crane and will be cleaned down before moving to its next job.

The tunnel is one part of a £150m fish protection package. Once the station is operating, fish drawn in with cooling seawater will be carried back out to the Bristol Channel through this pipe rather than being lost in the intake system. It sits alongside an acoustic fish deterrent and four low-speed water intakes designed so fish can stay clear of the plant. With this bore finished, EDF says more than eight kilometres of marine tunnel have now been dug under and around the Hinkley C site.

Why it matters

Hinkley C's workforce is expected to peak at around 10,000 people, and the project has moved through several distinct phases of labour demand since groundworks began. Tunnelling, which needs a narrow and specialist skill set, is now giving way on this particular package to the fit out, electrical and mechanical work that follows a completed bore. That handover from civils to M&E is already visible in current vacancies on site, where commissioning engineer roles sit alongside the tunnel agent positions tied to the KierBAM joint venture that has delivered this work.

For the wider nuclear supply chain, a finished tunnel is also a signal of project maturity. Contractors and specialist trades who built their CVs on Hinkley's early tunnelling and marine works are the same people Sizewell C's delivery teams are now trying to recruit, and EDF has been explicit that experience gained at Hinkley is meant to transfer up the coast. A completed package at one site tends to free people up for the other.

What it means for your career

If you're a tunnelling engineer, shift manager or marine civils specialist who has been on the Hinkley fish return job, this is the point to be having the conversation about what comes next, whether that's redeployment within the KierBAM JV, a move to Sizewell C, or another major UK infrastructure scheme now hitting its civils phase. Commissioning and M&E roles are the next wave of recruitment on this specific package, so electrical and controls engineers with nuclear-grade accreditation should expect live vacancies here over the coming months.

More broadly, this is a reminder that nuclear new build in the UK is no longer a one-site story. Hinkley's tunnelling specialists are a transferable pool that Sizewell C needs now, and the firms and recruiters who move fastest to place that experience will shape who leads delivery on the next phase of Britain's nuclear programme.