Celebrating the completion of the near 5,000-tonne heads

This month the Hinkley Point C Marine Works Team poured the final concrete pours of the six cooling water tunnel heads, completing the work ahead of time.

The first-of-a-kind head structures will cap the intake and outfall tunnels, which are currently being bored by three 1,500-tonne tunnel boring machines under the Bristol Channel.

Each of the four intake heads will be 44 metres long (roughly the length of four double-decker buses), eight metres high and weigh 4,650 tonnes. They will each have 775 tonnes of reinforcement, 125,000 individual reinforcing bars and 1,600m3 of concrete.

The two outfall heads weigh 3,500 tonnes each, with 250 tonnes of reinforcement, 52,000 individual reinforcing bars and 1,100m3 of concrete.

What happens next?

The next phase involves the transportation of the heads out into the Bristol channel which, at 13 metres, has the second highest tidal range in the world.

The heads will be lifted into place in the Channel by the largest marine cranes in the world, Gulliver and Rambiz - vessels that are bigger than a football pitch!

Due to the weight of the intake heads, the two vessels will lift each one in a combined operation known as a “tandem lift”. The tandem lift operation is complex and will be the subject of simulation trials over the course of this coming year. 

The outfall heads, being smaller, will each be lifted into position by one of the cranes.