Thames Water spills sewage into rare UK chalk stream for over 1,000 continuous hours amid fears of collapse

Troubled water firm Thames Water has been discharging sewage into a rare chalk stream continuously for over 1,000 hours since February 29. On its storm discharge map, which shows near real-time storm discharge activity through its monitors, it shows that Chesham Sewage Treatment Works has been spilling raw waste into the River Chess.

River Chess Association chair Paul Jennings posted on X, formerly Twitter, that it is “another unwanted milestone” while another user said the continuous discharge is “awful”. The River Chess is a chalk stream that rises near Chesham in the Chiltern Hills, and flows for 11 miles through Buckinghamshire and Hertfordshire. 

Last month Mr Jennings visited the site and told the Watford Observer the conditions were “as bad as I've ever seen”, adding that it was “deeply depressing” as there was “so much pollution”. The Chesham treatment works started discharging at 6.45am on February 29.

Today (April 11), the treatment works has spilled sewage into the chalk stream for over 1,000 hours. Paul Jennings posted on X today: “Another dubious milestone on the @RiverChess today as we pass 1000 hours of continuous sewage dumping from the @thameswater operated Chesham STW. This is un-permitted and action is needed by @EnvAgency, we would expect sanctions.”

It comes as Thames Water is reportedly exploring radical plans to avoid collapse after it has racked up a debt pile worth at least £14.7bn. As part of urgent restructuring talks, the firm’s executives are considering breaking Thames up into two smaller companies covering London and, separately, the Thames Valley and Home Counties regions, according to The Telegraph. 

The water firm is scrambling to shore up its finances after its parent company, Kemble, defaulted on its debts. Shareholders have also refused to provide new funding and fears are mounting that taxpayers could be left to foot the bill if the government has to bail out the company. According to The Daily Mail, Rothschild, the investment bank, has been hired to advise Thames Water on how to deliver its reform plan, while consultancy firm Teneo has been appointed as 'administrator in waiting' to take over in the event of a collapse.

A Thames Water spokesperson said: “We regard all discharges as unacceptable and we have published plans to upgrade over 250 of our sewage treatment works, including at our Chesham Sewage Treatment Works. This is currently being upgraded at a cost of £20 million and is expected to be completed this year. The improvements will increase our ability to treat the high volumes of incoming sewage at 353 litres per second and reduce the need for overflows during wet weather. 

“The overflows are designed to operate automatically when the sewer network is about to be overwhelmed, by releasing diluted wastewater into rivers, rather than letting it back up into people’s homes. Taking action to improve the health of rivers is a key focus for us and we are leading the way with our transparent approach to data. We remain the only water company to provide live alerts for discharges to our customers and environmental groups.”