A tunnelling machine has broken through the seabed under the Bristol Channel after finishing a 620-metre fish return tunnel at the UK’s Hinkley Point C NPP site. According to EDF, the machine, named Sarah Guppy, dug its way out of the seabed five months after setting off from dry land and has now been lifted clear by a floating crane. It will be taken away to be cleaned before being used at another site.
The tunnel, which is 1.8 metres in diameter, is the last of the project’s marine tunnels under the channel, which have a total length of eight kilometres. The fish return system is one of three measures designed to protect marine life around the site. These will give the station more fish protection than any other power station in the world, EDF noted.
The other measures are an acoustic fish deterrent and four low-speed water intakes. The intakes are designed so that fish can swim safely away from as close as two metres in the 20-kilometre-wide channel. Any fish that do enter the cooling system will be carried back out to sea through the new tunnel.
The tunnel boring machine was named Sarah Guppy by local schoolchildren, after the 19th-century Bristol engineer. Engineers prepared to start the drive in March.
