Anglian Water fined £560k for sewage release in Essex waterway
A water company said it "deeply regretted" failures that resulted in the release of millions of litres of sewage into a river and a £536,000 fine.
Anglian Water admitted failures in managing its water recycling centre near Brentwood in Essex.
The pollution killed fish along a 3km (1.8 miles) stretch of the River Wid in 2018, the Environment Agency said.
District Judge Sam Goozee described Anglian Water's record as "lamentable".
The offence of causing water discharge activity took place between 27 September and 2 October 2018.
Chelmsford Magistrates' Court was told a fault in an aeration process at the Doddinghurst water recycling centre at Wyatts Green meant 3.9 million litres of sewage was discharged into Doddinghurst Brook - a tributary of the River Wid.
It went unchecked for nearly three days, damaging the river's ecosystem and killing a number of a protected fish species, including the freshwater bullhead, the agency said.
It added that the pollution could been avoided had Anglian Water spent £205 on software for an early alarm system.
It was the second time in six months that Anglian Water had been fined for polluting the same stretch, the agency said.
The water company, whose headquarters are in Huntingdon in Cambridgeshire, was also ordered to pay costs of £27,439.21 and a victim surcharge of £170.
Environment Agency officer Gavin Senior said the public demanded tough action when it came to water quality.
"The invertebrate and fish population in this area, including a protected species, suffered significantly because of this sewage pollution and it took time for the local ecosystem to recover," he said.
In a statement, Anglian Water said it "deeply regretted any negative impact" and had donated £60,000 to the Essex and Suffolk Rivers Trust.
"We take our duty of care to the environment incredibly seriously .. and find it deeply distressing when incidents like this occur," the company said.
"We know there's no room for complacency, and we're absolutely determined to improve further and progress towards achieving our zero pollutions goal."
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