Steam being pumped from Heysham Power Station is the result of an unplanned shutdown, says operator EDF Energy.
Steam is being vented from Heysham 1, following an issue with a water valve.
A spokesman for EDF Energy, which owns and operates the nuclear power station said: “Heysham 1’s reactor 2 was shutdown at 8.45am on July 26.
“As part of the power station’s usual practice after a shutdown steam was vented from the site.
“The shutdown was unplanned and followed an issue with a condensate water valve which is on the conventional part of the station.
“The site will now look to return the reactor to full operation.”