United Utilities has been ordered to pay £666,000 for 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, which had a significant impact on fish population and water quality over four kilometres.
A member of the public initially reported the pollution on 14th October 2014.
United Utilities estimated around 21,7000 cubic metres of sewage was discharged into the water.
The water firm apologised to its customers and said it is investing £6 billion in the North West until 2020 and making “major environmental improvements”.
Wastewater Network Director Keith Haslett added: “The incident was caused by a faulty control valve at our wastewater facility in Oldham. The valve door failed, due to a worn drive nut.
“In the three years since the incident, we have upgraded alert systems, introduced new alarm procedures and enhanced the control valve. We are investing a further £50 million in improvements along the River Medlock.”