South West Water has been ordered to pay £205,000 after more than 700,000 litres of sewage polluted an internationally important shellfishery in Cornwall.
The incident, in August 2013, occurred at water company’s Newham sewage treatment works near Truro and involved untreated sewage entering the Fal estuary, which is a site of special scientific interest (SSSI) and special area of conservation (SAC).
The spill was caused by a piece of redundant grating, which fell and partially blocked an inlet at the works, causing sewage to back up and overflow into the estuary via a storm storage outfall. The overflow continued for almost ten hours, during which time 730,000 litres of sewage escaped.
The discharge was close to mussel and oyster beds at Malpas and Grimes Bar and Cornwall Port Health Authority was fored to temporarily close the shellfisheries due to the risk of contamination by Norovirus and e.coli bacteria. Although the pollution took place outside the main commercial season, the authority said it had wanted to protect people hand-picking shellfish.
Mark Pilcher, team leader for the Environment Agency in west Cornwall, said: ‘It is essential large sewage works bordering estuaries with conservation designations and also containing shellfish beds are operated and inspected to a high standard to prevent unpermitted sewage spills posing risks to public health and the environment.
‘In this case an inspection programme or removal of a redundant grating structure would have removed the risk of this grating falling into the sewage works and blocking it leading to the spill of sewage,’ he said.
South West Water was fined £185,000 plus £20,000 costs after pleading guilty to two offences under the environmental permitting regulations 2010. The case was heard at Truro Crown Court.
A spokesperson for South West Water said: ‘We acted promptly to clear the blockage, notified the agency and Cornwall Port Health Authority within 24 hours and took action to prevent this unforeseen incident reoccurring. The discharge had a minimal impact on the receiving water quality and the event took place outside the oyster harvesting season.’
