Truro Crown Court heard how between July 9 – 23, 2013 the company’s sewage treatment works at Luxulyan near St Austell was not operating properly. This resulted in poorly treated sewage effluent discharging into the Par River. The case was brought by the Environment Agency.
South West Water is required, under its site permit, to ensure the treatment works operates correctly and notify the Environment Agency of any problems that might affect effluent quality. Treated effluent must be of a standard that does not cause pollution.
An Environment Agency officer visited the treatment works on July 18 and immediately realised there was a ‘serious problem’ at the plant.
A final effluent sample had a biochemical oxygen demand (BOD) of 66.4mg/litre. This exceeded the site’s maximum permitted limit of 56 mg/litre. Under normal conditions final effluent should not have a BOD above 20mg/litre.
Further checks revealed that one of five surface aerators had been taken out of service in March 2013 and not yet been repaired or replaced. The treatment system can cope without one surface aerator, but when a second aerator failed in July, the works could no longer function properly.
Phil Christie for the Environment Agency said:
The site wasn’t being managed and maintained properly. South West Water took an unreasonably long time to repair a broken aerator (March to September) and this meant the works were running at a significantly reduced efficiency. The company didn’t spot problems quickly enough or respond with the speed and urgency required.
It is estimated that during the incident, nearly one tonne of poorly treated sewage effluent was discharged into the Par River every minute. The discharge had an impact on river ecology for a quarter of a mile downstream of Luxulyan with a thick growth of sewage fungus over 175 metres the riverbed.
The court heard the system used to kill viruses and bacteria at the treatment plant (UV disinfection) was significantly undermined by the poor quality sewage effluent. The River Par enters the sea at Par beach some 7 km downstream of Luxulyan. Cornwall Council posted warning signs on local beaches after the Environment Agency declared an ‘abnormal situation.’
At a sentencing hearing at Truro Crown Court, Judge Harvey Clark fined South West Water a total of £150,000 for three offences under the Environmental Permitting (England and Wales) Regulations 2010 including failing to return Luxulyan sewage treatment works to normal operation as soon as practicable, exceeding the Biochemical Oxygen Demand (BOD) discharge limit of 56mg/l and failing to inform the Environment Agency of any failure that may adversely affect effluent quality. The company was also ordered to pay £3,600 costs.
In his summing up, Judge Clark said, after studying the evidence, he was satisfied South West Water was guilty of negligence. Staff at Luxulyan sewage treatment works, he said, had ‘lacked proper vigilance’ and the company had failed to put in place adequate personnel or proper systems at the site to ensure offences did not occur.
Fines for environmental offences committed by utilities and other large companies are likely to be significantly higher following recent judgements in the Court of Appeal and new Sentencing Guidelines.