Thames Water fined £380K for sewage pollution

Thames Water has been fined £380,000 at Aylesbury Crown Court for polluting the Horsenden Stream in Buckinghamshire.

The case was brought by the Environment Agency after Thames Water caused pollution from its site at Princes Risborough sewage treatment works to enter Horsenden Stream, part of the River Thame catchment area in the Chilterns,

Thames Water pleaded guilty at Wycombe Magistrates Court on August 5, 2015 and was committed to Aylesbury Crown Court for sentence. On Monday (March 7), the company was also ordered to pay costs of £23,092.64 and a victim surcharge of £120.

The ongoing management failures at a site the court described as clapped out were lamentable and caused the company to breach the site permit on a number of occasions between February and July 2013.

The court heard how in February 2013 an officer conducting an unrelated fisheries survey of the stream had to stop for his own welfare because of the level of sewage in the stream. The Recorder of Aylesbury, His Honour Judge Sheridan, noted that if it was not for the fisheries survey the incidents were unlikely to have come to light due to the unacceptable level of management failures at the site.

A further discharge was seen by officers during a site visit on March 5, 2013 when the sewage in the stream looked like feathers in places, and again on July 19, 2013, the latter being caused by a blockage in the works.

The conditions of the environmental permit set by the EA aim to prevent pollution of the stream. The permit also allows Thames Water to discharge sewage during storm conditions as long as stringent conditions are met.

Between February and July 2013 the site was poorly managed and there were ongoing problems. Storm discharges into the stream were either observed or recorded in the log book on 21 occasions.

The inlet screens, designed to prevent debris from entering the works and causing blockages, were not working and the storm tank pump was broken. The site’s storm weir was also set too low which meant that discharges were happening when the effluent should have been passing through the works for treatment.

Environment officer Holly Linham said: “Our officers attended the site where they walked the Horsenden Stream and saw thick layers of sewage fungus carpeting the river bed and plants. One of the officers had never seen sewage fungus in a stream that bad before. A biological survey of the stream noted that the impact of the sewage was chronic and was likely to have been prevalent for some time.”

In sentencing the court gave Thames Water full credit for its early plea. The company has since changed the management structure at the site and raised the storm weir. As a result, the stream has improved.

The court placed on record the company’s commitment to improving its environmental performance and noted that it could face significantly higher fines in future if it did not stay true to its word.