In a prosecution brought by the Environment Agency, United Utilities has been fined £666,000 after pleading guilty to polluting a river with untreated sewage effluent in Greater Manchester.

The water company was prosecuted following a pollution incident which saw an estimated 21,700 cubic metres of sewage discharged into the River Medlock

A member of the public initially reported the pollution on 14 October 2014 to the Environment Agency’s incident hotline.

United Utilities staff 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 when the pollution was first reported.

Environment Agency officers found that the pollution had deposited grey sludge on the River Medlock’s bed over four kilometres resulting in significant impact on fish population and water quality.

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

Mark Easedale, Environment Manager for Greater Manchester, said:

“The Environment Agency take pollution incidents very seriously and this case should send a strong message to companies of the potential consequences if they damage the environment.

“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 we avoid such incidents in the future.”

The court heard that the utility had subsequently taken a number of steps to prevent a reoccurrence of the incident, which was caused by a faulty control valve at the wastewater facility in Oldham.  The valve door failed, due to a worn drive nut.

 In the three years since the incident the water company has upgraded alert systems, introduced new alarm procedures and enhanced the control valve. It is also investing a further £50 million in improvements along the River Medlock.

In a statement, Keith Haslett, Wastewater Network Director at United Utilities, said:

“We are investing £6bn in the North West over the five years to 2020 and making major environmental improvements, but we failed in our responsibility on this occasion. We apologise to our customers because we do care, both personally and professionally.

“We are proud of our partnership with environmental groups across our region, and continue to work with them to improve rivers and the local environment. This fine will be paid by shareholders and not customers.”

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