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. A group of 44 visitors was inside the underground building at the time attending a public presentation by North West Water Authority (NWWA) 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 (1,200 m) 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.
The Abbeystead valve house was constructed as part of NWWA's 'Lancashire conjunctive use scheme,' a water supply project "to help in meeting the region's expected increases in water demand during the 1980s." The scheme involved the daily extraction of up to 62 million imperial gallons (280,000 m3) of water from the River Lune near Lancaster which was then pumped through Abbeystead into the River Wyre. From here it would be extracted to a treatment works to augment the drinking water supply for south Lancashire.
The visitors were from the village of St. Michael's on Wyre, situated approximately 10 miles from the valve house and which had previously suffered flooding which residents believed was caused by the station pumping water from the River Lune to the River Wyre. The tour of the valve house had been arranged by NWWA to alleviate public concern about the flooding. George Mann, chairman of NWWA, said that the tour was intended to have a "family flavour." The tour commenced at 7.20pm and the explosion occurred approximately 10 minutes later, with the first telephone call to the emergency services logged at 7.37pm. Oliver Chippendale, the supervisor of a pumping station on the River Lune had received a telephone call from George Lacey, the NWWA district manager conducting the tour, asking him to commence pumping, and a second call 5 minutes later saying that no water was coming through and to activate a second, larger, pump. Twenty minutes later Chippendale called Abbeystead to check water was coming through and the telephone was answered by water engineer John Nelson who shouted "Get help! There has been a terrible disaster!" The force of the blast had lifted 30 concrete roof beams, each weighing 2½ tons, upwards through the soil landscaping above them before they fell into the chamber below.
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