By Nerijus Adomaitis and Gwladys Fouche
OSLO (Reuters) - A fierce storm in the North Sea forced oil firms to evacuate rigs and shut down production on Thursday, with drilling installations under threat from a drifting barge that strong winds had ripped from its anchor.
BP said it was evacuating staff from its Valhall platform while ConocoPhillips shut down output at its Eldfisk and Embla fields and was removing crew from its Eldfisk platform.
The evacuations came a day after one person died and two were injured when a big wave hit a rig belonging to China Oilfield Services Ltd that had been drilling at the Statoil-operated Troll field, also in the North Sea.
Norway has been experiencing stormy weather since Wednesday, which caused a sea barge to break its anchor and head toward the rigs.
"The barge has changed direction and BP has decided to shut production (at Valhall) and there will be a total demanning of the platform. There are 71 people left on the platform and they are being evacuated as we speak," a BP spokesman told Reuters.
The barge was less than 10 nautical miles from the platform.
"If it continues in the same direction, it will be there in two hours," a spokesman at the Rescue Coordination Centre for southern Norway told Reuters.
"(Rescue boats) are trying to establish a new towing line, and we have a good hope that it can be successful... The weather is about the same as it was during the night, with waves at 10-15 metres high."
The Norwegian oil safety watchdog said that the barge could inflict severe damage if it hit the platform.
"(The barge) is a very big structure and if it hits the platform it can inflict a very severe damage, so it was a wise decision to evacuate the platform," a spokeswoman for the Norwegian Petroleum Safety Authority told Reuters.
The field's production was shut, BP said. The field, operated by BP and co-owned by Hess, was producing at a rate of about 50,000 barrels per day before the shutdown.
On Thursday, the China Oilfield Services Ltd (COSL) rig which experienced a fatality was making its way to the Norwegian coastline and was expected to reach land later in the day.
Close to 50 people out of 106 staff onboard, whose living quarters were damaged during the storm, have already been evacuated.
"The weather was rough during the accident, with waves as high as 14 metres and wind speed 25 to 30 metres per second. Strong winds prevented a helicopter from landing on the rig and people had to be lifted," Eileen Brundtland, a spokeswoman at the Norwegian Petroleum Safety Authority, told Reuters.
Production at the Troll gas field, Norway's largest, was not affected as the installation was a drilling rig, not a production facility, a Statoil spokesman said.
(Writing by Gwladys Fouche; Editing by Toby Chopra)