Water company prosecuted for illegal discharge

Water company prosecuted for illegal discharge from sewage treatment works

Wessex Water was ordered to pay £ 6,978 in fines and costs for releasing poor quality effluent from a sewage treatment works in Hampshire. The case was brought by the Environment Agency.

Ringwood Sewage Treatment Works is owned and operated by Wessex Water Services Limited. The company is permitted to discharge treated sewage into a nearby watercourse – the Bickerley Millstream, a tributary of the Hampshire Avon at Ringwood. Effluent must be of a certain standard to protect the receiving water from pollution.

The Environment Agency regularly samples the effluent to ensure the treatment works complies with the conditions of its discharge consent.

The Hampshire Avon is a high quality river and has been designated as a Special Area of Conservation under the Habitats Directive. The river is an important Atlantic salmon spawning area.

Samples are taken 12 times a year and limits set for certain chemicals such as ammonia, which is extremely toxic to river life. The sampling also measures how much oxygen is removed from the water by the pollutant, which is known as the biochemical oxygen demand (BOD).

On September 23 2006, a call was received by the Environment Agency from a member of the local angling club saying that the Bickerley Millstream below the sewage treatment works discharge point was discoloured and had an unpleasant odour.

An Environment Officer attended the Ringwood sewage treatment works and found thick brown liquid was flowing out through the gateway into the road. Further investigation found a valve on a sludge tank had been left open after routine maintenance. This led to effluent flowing continuously from the primary tank to the sludge storage tank, which overfilled.

New Forest Magistrates heard how the biochemical oxygen demand (BOD) exceeded the permitted limit. An ultrasonic level detector on the sludge storage tank, which would have raised the alarm to the pollution, was monitoring an empty tank that was not being used rather than the one overflowing.

‘The Hampshire Avon is a high quality river suitable for salmon and sea trout. Both these species of fish are vulnerable to pollution. Sewage treatment works have the potential to pollute, so it is important water companies operate in such a way so as to ensure these works fully comply with the conditions of their discharge consents,’ said Emma Tattersall for the Environment Agency.

Wessex Water Services Limited, of Claverton Down Road, Claverton Down, Bath, was fined £ 6,000 and ordered to pay £ 978 costs by New Forest magistrates at Lyndhurst after pleading to one offence under Section 85(6) of the Water Resources Act 1991 of breaching a condition of its discharge consent at Ringwood Sewage Treatment Works and causing sewage effluent to enter Bickerley Millstream.