Abbeystead disaster

The Abbeystead disaster occurred on the evening of 23 May 1984 when a methane gas explosion destroyed a waterworks' valve house at Abbeystead, Lancashire, England, killing 16 people. A group of 44 visitors were inside the underground building at the time attending a public presentation by North West Water Authority to demonstrate the operations of the station. Eight were killed instantly by the explosion, and the others were severely injured. The explosion also caused the concrete roof to fall down on to the group, destroying the steel mesh floor and throwing some of the victims into the water chambers below which rapidly filled with river water. Another eight people subsequently died of their injuries in hospital. An 11-year-old boy and his mother were among the dead. The official inquiry into the disaster concluded that the methane had seeped from coal deposits 3,937 feet below ground and had built up in an empty pipeline. The gas was then ejected into the valve house by the sudden pressure of water as the pumps were switched on. The cause of ignition has never been determined.

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