Various outlets including Utility Week reported that United Utilities has been ordered to pay a fine of £666,000 after pleading guilty to polluting a river with untreated sewage effluent in Greater Manchester.

The Environment Agency took the prosecution against the water company after sewage polluted the River Medlock, having a significant impact on the fish population and water quality.

A member of the public initially reported the pollution in the River Medlock at Park Bridge, in Ashton-Under-Lyne to the Environment Agency’s incident hotline in October 2014.

Officers found that the pollution had deposited grey sludge on the River Medlock’s bed over 4 kilometres, resulting in significant impact on fish stocks and water quality in the river.

In total United Utilities estimated that 21,700 cubic metres of sewage discharged into the water.

A report commissioned by United Utilities found that the incident had a detrimental impact on brown trout and had the potential to reduce the fish population the following year.

When the pollution was first reported, United Utilities officers were attending a high-level alarm at the Sewage Tank and had identified a fault which meant the tank was not emptying to the foul sewer network as quickly as it should have been. This resulted in untreated raw sewage entering Glodwick Brook and the River Medlock.

United Utilities admitted that its control centre had received an alarm about the discharge three days before, but the fault had not been recognised.

In sentencing, HH Judge Potter said the company’s negligence had resulted in significant harm to the River Medlock.

Mark Easedale, The Environment Agency’s environment manager for Greater Manchester, said: “The sewage that was discharged had a significant impact on the River Medlock, killing brown trout, which are a key indicator species of good water quality. The case demonstrates just how important it is that water companies and wider industries maintain their equipment in order to prevent pollution to the environment.

“We work closely with United Utilities who have undertaken extensive work to reduce their impact on the environment. It’s important that we continue to work with partners in order to safeguard the environment and ensure such incidents are avoided in the future.”

In mitigation United Utilities told the court of the steps it had taken to prevent a reoccurrence of this incident.

The company was fined a total of £666,000 and ordered to pay costs of over £32,000.