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Thames Water ordered to pay record £20 million for river pollution

Thames Water Utilities Ltd sentenced in the largest freshwater pollution case ever taken by the Environment Agency.

Thames Water Utilities Ltd (Thames Water) has today (22 March) been fined an unprecedented £20,361,140.06 in fines and costs for a series of significant pollution incidents on the River Thames. These offences were caused by negligence and led to the death of wildlife and distress to the public.

The prosecution saw 6 separate cases - which caused widespread, repeated, sustained and avoidable pollution at a number of sites from 2012 to 2014 - brought together in one hearing at Aylesbury Crown Court. It is the biggest freshwater pollution case in the Environment Agency’s 20 year history.

The court heard how TWUL’s repeated illegal discharges of sewage into the River Thames, and its tributaries, resulted in major environmental damage including visible sewage along 14 kilometres of the river, and the death of birds, fish and invertebrates.

The multiple incidents from the company’s wastewater sites in Oxfordshire, Buckinghamshire and Berkshire caused significant distress and disruption to the public. Riverside residents, farmers, local businesses, anglers, and recreational river users were all affected. Sailing regattas and other events on the River Thames were also disrupted.

Investigations carried out by Environment Agency officers revealed a catalogue of failures by TWUL management. This involved repeated discharges of untreated or poorly treated raw sewage into rivers, disregarding risks identified by their own staff and failing to react adequately to thousands of high priority alarms used to alert them to the serious problems.

The Court heard how for weeks, untreated sewage, amounting to millions of litres per day, was diverted to the rivers and away from the treatment process, although the incoming sewage flow was well within the designed capacity of the treatment works. In many instances less than half of the incoming sewage was sent for treatment.

It was pointed out to the Court that local residents impacted by the pollution were also customers of TWUL and were paying the company to have their sewage treated to the legally required standards - standards which protect the environment.

Sir James Bevan, Chief Executive of the Environment Agency, said:

Water and sewerage companies provide a vital service to the community. Where they experience problems through no fault of their own we will always work with them to resolve them but where negligence causes serious pollution, or a serious threat to the environment, we will seek the strongest possible penalties.

This case sends a clear signal to the industry that safeguarding the environment is not an optional extra, it is an essential part of how all companies must now operate.

His Honour Judge Sheridan, condemned the “disgraceful conduct” of Thames Water Utilities Limited, which he said was “entirely foreseeable and preventable.”

It was “a very dark period in the history of Thames Water” who demonstrated “scant regard for the law, with dreadful results for people who live in the area.”

He congratulated the Environment Agency for their “painstaking and thorough investigation”, and added that he hopes the courts never see the like of such a case again.

When commenting on the level of the fines, His Honour Judge Sheridan, noted this was a record breaking fine for record breaking offending. He asks that the fines must be met by Thames Water, and not be passed onto customers; it was the company, not the customers, who broke the law.

Anne Brosnan, Chief Prosecutor for the Environment Agency said:

Thames Water was completely negligent to the environmental dangers created by the parlous state of its works. Our investigation revealed that we were dealing with a pattern of unprecedented pollution incidents which could have been avoided if Thames Water had been open and frank with the Environment Agency as required by water company industry protocol.

Members of the public are our eyes and ears so if you see any signs of pollution in a watercourse near you please report it to the Environment Agency Incident Hotline on 0800 80 70 60.

The offences caused officers to work around the clock for lengthy periods, responding to reports of pollution, attending to clean up and river recovery and in undertaking very detailed and complex investigations. The ongoing investigation included intelligence gathering, monitoring, interviews and analysis by the Environment Agency and resulted in bringing the company to court to face the consequences.


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Fines and costs:

  • Fines for each charge
  • Little Marlow: £8,000,000
  • Aylesbury: £9,000,000
  • Henley: £1,000,000
  • Littlemore: £800,000
  • Didcot: £800,000
  • Arborfield: £150,000

Costs: £611,140.06

TWUL had already been fined £1million and £380,000 in 2016 for similar problems in 2013 at 2 of their other sewage treatment works at Tring in Hertfordshire and Princess Risborough in Buckinghamshire in earlier cases brought by the Environment Agency.

The Court was informed that TWUL had already been convicted, in individual prosecutions, of pollution offences at six other sites in the same period of time as the six cases before the court – mid 2012 to early 2014.Thames Water have attempted to maintain that these offences are the result of unprecedented wet weather and also the result of the public putting products such as wipes and condoms down the loo. Firstly, the Environment Agency were careful to exclude the periods of wet weather as a cause of the offences charged and, secondly, modern sewage equipment, properly maintained, can and does cope with the contents of foul sewers – as the operation of the same works with properly operating equipment is now demonstrating.

List of charges:

  1. Aylesbury STW polluted the River Thame, a tributary of the River Thames in Buckinghamshire, between January 2013 and November 2013. TWUL had previously been prosecuted in 2004 for offences at this STW in 2002. There were 2 distinct and repeated illegal actions at Aylesbury STW which resulted in pollution of the River Thame. One was the by-passing of the treatment process by up to half of the incoming flow of untreated effluent and its discharge, untreated, into the river. The other was the diversion, at the end of the treatment of process, of poorly treated effluent away from the only permitted outfall and sampling point into the river, through a disused and unauthorised land treatment area and thence to the river. Amongst the persons affected were a cattle farmer who lost the value of a prime beef cow due to a human tape worm and a professional crayfish fisherman who suffered losses of £25,000 in 2013 and further losses in the next 3 years.

  2. Little Marlow STW, polluted the River Thames, Thames Path and farmland both directly and via the Spade Oak Brook in Buckinghamshire between November 2012 and December 2013. The most serious pollution incident ever recorded in the River Thames from Little Marlow Sewage Treatment Works (STW) resulted in over 100 complaints from the public about sewage in the water. The water company’s inadequate investment, maintenance and poor management caused months of misery for local communities and visitors and affected the River Thames for over 1km.

  3. Henley Sewage Treatment Works (STW), polluted the River Thames via the Fawley Court Stream in Oxfordshire between May 2013 and June 2014. Pollution from Henley STW caused the death of fish and had a detrimental and long term impact on Temple Island Meadows a Site of Special Scientific Interest (SSSI), in particular aquatic invertebrates.

  4. Didcot STW, polluted the Moor Ditch, a River Thames tributary in Oxfordshire, in April 2013. Pollution from Didcot STW was spotted by a cyclist who saw a black cloud of polluted water containing toilet roll, sanitary towels and other solids. Environment Agency officers spotted extensive sewage fungus in the watercourse. TWUL managers were regularly made aware of issues by their own staff including that the storm tanks were ‘black and septic’ and that ‘if storm tanks discharge to stream fish kill imminent.

  5. Littlemore Sewage Pumping Station, polluted the River Thames in Oxfordshire between February 2013 and April 2013.’Pollution from Littlemore Sewage Pumping Station (SPS) created a visible plume of brown raw sewage. The TWUL ‘clean-up’ was not adequate, leaving sewage debris and black colouration to the channel and causing months of misery for local communities.

  6. Arborfield STW, pollution of Barkham Brook, tributary of the River Loddon in Arborfield Berkshire on 29 September 2013 untreated sewage discharged from the storm tanks due to faults with the inlet pump systems and failure to heed alarm and telemetry systems, causing a significant water pollution incident, resulting in the deaths of a significant number of fish in the river, as well as other flora and fauna


Channel website: https://www.gov.uk/government/organisations/environment-agency

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