Camelford Water Pollution Incident - Cause

Cause

On 6 July 1988 John Stephens, a relief tanker driver working for Bristol-based distribution firm ISC, arrived at Lowermoor Water Treatment Works on Bodmin Moor and found it unmanned. Being unfamiliar with the location, he had been given a key by another driver and told simply that "once inside the gate, the aluminium sulphate tank is on the left". However, the key fitted almost every lock used by the South West Water Authority (SWWA). After twenty minutes looking for the correct tank he tried the key on a manhole cover and when it unlocked believed he had accessed the correct tank. He poured the load of 20 tonnes of aluminium sulphate, used to remove solid particles from cloudy water, into the tank, which actually held treated water prior to distribution to the consumers in Camelford. This immediately contaminated the water supply to 20,000 local people and up to 10,000 tourists. The maximum recorded aluminium concentration was 620,000 micrograms per litre compared with the maximum concentration admissible at the time by the European Community of 200 micrograms per litre.