The Abbeystead Explosion. 23rd May 1984
On Wednesday 23 May 1984, a group of 44 people was assembled in a valve
house set into a hillside at the outfall end of the Lune/Wyre Transfer
Scheme at Abbeystead. The visitors were attending a presentation to allay
anxieties on the effects of the installation on the winter flooding of the
lower Wyre Valley.
As part of this presentation, water was to be pumped over the weir
regulating the flow of water into the Wyre. Shortly after pumping commenced
there was an intense flash, followed immediately by an explosion causing
severe damage to the valve house.
Sixteen people were killed; no one escaped without injury from the valve
The explosion was caused by the ignition of a mixture of methane and air,
which had accumulated in the valve house. The methane had been displaced
from a void, which had formed in the end of the Wyresdale Tunnel during a
period of 17 days before the explosion when no water was pumped through the
No source of ignition for the explosion has been positively identified.
Thorough examination and testing of the electrical equipment has not
revealed any faults likely to have caused ignition and there is insufficient
evidence to confirm any of the other explanations which have been
considered. Smoking in the Valve House was not prohibited because the
likelihood of a flammable atmosphere arising there had not been envisaged.
Failings in technical measures
- The possibility of a methane rich environment had not been recognised.
The fact that large quantities of methane might be dissolved in water,
which subsequently leaked into the system, was not considered by those
involved with the design/operation of the system. A system designed for
discharging water open to the atmosphere would have prevented an
- Design Codes - Plant: ventilation of
- Leak / Gas Detection: Positioning
- The operation of the plant was not in accordance with the operating
manual provided by the designers of the systems. Changes in the
operating procedures had taken place without proper consultation as to
- Operating Procedures: human
- Operators were not fully aware of the significance of special features
of the pumping installation.
- Training: Operator training,
Health and Safety Executive, ‘The Abbeystead explosion : a report of
the investigation by the Health and Safety Executive into the explosion on
23 May 1984 at the valve house of the Lune/Wyre Water Transfer Scheme at
Abbeystead’, ISBN: 0118837958, 1985.