Thames Water, the UK’s largest water company, has been fined £2.3m for a pollution incident in 2016 that resulted in the death of 1,200 fish and damaged the environment. The incident, involving a leak of untreated sewage with a high ammonia content into the Fawley Court ditch and stream that flows into the River Thames at Henley-on-Thames, happened between 21 and 24 April 2016. The prosecution and sentencing of Thames Water, which pleaded guilty to the Environment Agency’s charge, was delayed until this week for reasons including the pandemic. Francis Sheridan, the judge in the case, which was heard at Aylesbury crown court, said Thames Water’s breach of environmental standards constituted “high negligence”. The company received a record £20m fine in March 2017 for a series of pollution incidents at sewage facilities in Buckinghamshire and Oxfordshire that led to the pumping of 1.9bn litres of untreated sewage into the Thames. In the latest case, the court heard that Thames Water’s warning systems of low levels of oxygen in the water had been activated over a number of days, but that effective action had not been taken in response. Sheridan said he wanted a deterrent element to be built into the sentence and for that reason he had set the fine high. Thames Water initially sought to get the case dismissed, but the judge rejected its attempt as hopeless. He accepted in mitigation, however, that Thames Water had taken significant steps to improve matters since the incident. Its eventual decision to plead guilty to the offences was also recognised as a mitigating factor. Sailesh Mehta, instructed by Rooma Horeesorun, the Environment Agency’s senior lawyer, welcomed the sentence and large fine. “This fine reflects the growing trend in courts to acknowledge the seriousness of environmental offences of this kind and shows how the courts are playing a vital role in protecting the environment for future generations,” he said. It was reported this month that Thames Water had been discharging untreated sewage into a chalk stream in Buckinghamshire, which campaigners say has caused untold harm to trout fry and river habitats. Thames Water’s CEO, Sarah Bentley, who joined the company in September, said: “We’re really sorry for what happened in Henleyfive years ago. Discharges of untreated sewage are simply unacceptable and we will work with the government, Ofwat and the Environment Agency to accelerate work to stop them being necessary. “Our business plan for the next five years includes an unprecedented amount of investment, much of it directed towards safeguarding the environment. We have a long way to go and we certainly can’t do it on our own, but the ambition is clear.” An Environment Agency spokesperson said: “This £2.3m fine for Thames Water for an entirely foreseeable pollution incident in 2016 laid bare the company’s management failings. “Protecting England’s rivers and lakes is one of the Environment Agency’s top priorities. Our enforcement action over several years has led to improvements in how water companies operate, but the damage caused to the environment at Henley shows water companies have a lot more to do. Sitting at Aylesbury Crown court today, Judge Francis Sheridan said a number of equipment faults at Thames Water’s local sewage treatment plant should have been identified and fixed ‘long before’ the company reacted.”