The water industry watchdog has launched an investigation into five firms over “serious concerns” about how they manage wastewater treatment.
Ofwat said Anglian Water, Northumbrian Water, Thames Water, Wessex Water and Yorkshire Water were set to be probed.
The regulator said it followed data in December that “suggested widespread shortcomings in how water companies were running sewage treatment works”.
The water firms told the BBC they would cooperate with Ofwat’s investigation. It has the power to fine companies up to 10% of their annual turnover.
David Black, Ofwat’s interim chief executive, said: “The data that emerged at the end of last year suggested widespread shortcomings in how water companies were running sewage treatment works. The first phase of our investigation suggests those concerns are credible. We have identified shortcomings in most water and wastewater companies and are continuing to investigate. But we have already seen enough in five companies to cause serious concern and warrant us taking further action.”
Ofwat said the companies had been targeted because data supplied by them in December showed a “significant number” of treatment works “might not be compliant with its environmental permits”. It added that there were also concerns about how the companies managed their environmental obligations. The watchdog said it also continues to monitor Southern Water’s compliance with a package of commitments it made following enforcement action in 2019.
Richard Warneford, wastewater director for Northumbrian Water, said the firm recognised “the gravity of the investigation” and would “fully comply with the requests made”.
A Thames Water spokesperson said the firm was “committed to transparency” and had already been developing a plan to “radically improve our position in order to protect and improve the environment”.
Wessex Water said it was undertaking a “thorough investigation” at its treatment works, and was “working with Ofwat to provide the further information they have now requested”.
An Anglian Water spokesperson said: “We’ve been transparent throughout and the regulator could have asked us at any point for further detail, which we would have provided.”
Yorkshire Water added that it took its “commitment to care for the environment very seriously” and would “be cooperating fully with the investigation”.