The Mühleberg nuclear power plant, near Bern, will be temporarily shut down and withdrawn from the power grid on Thursday, it has been announced.
The BKW electricity company, which runs the plant, said that the move, five weeks before the scheduled annual inspection, was to implement measures to safeguard the cooling water extraction.
After the measures have been completed in September, the plant should be reconnected, a statement said. The cost of the work is estimated at around SFr20 million ($24 million), according to the Swiss News Agency.
“BKW is working with high priority and due diligence to meet the additional safety requirements as required by the Swiss Federal Nuclear Safety Inspectorate (ENSI) in the wake of Fukushima,” said the company.
On June 30 BKW will present proof that it can deal with a one in 10,000 year flood. But experts say that in certain exceptional situations a blockage in the water cooling system could occur.
The new safety measures will therefore concern this aspect, as well as flood safety at an existing pump station.
Switzerland has announced that it is to opt out of nuclear power by 2034.
Reacting to the BKW announcement, environmental organisation WWF Switzerland said that Mühleberg should only be reconnected to the grid when all the problems discovered over the past years had been resolved. This included cracks in the reactor core shroud, it said.
swissinfo.ch and agencies