Water regulator Ofwat has proposed £47 million of fines for Yorkshire Water for failing to manage sewage spills, within the first batch of results from its biggest ever investigation into the industry.

The penalties relate to the water firm’s management of their wastewater treatment and sewer systems, which have come under heavy criticism for releasing too much pollution into rivers.

Ofwat also proposed fines of £104 million for Thames Water and £17 million for Northumbrian Water under the same investigation.

In an announcement this morning (Tuesday, August 6), Ofwat said the firms ‘failed to ensure that discharges of untreated wastewater from storm overflows occur only in exceptional circumstances, which has resulted in harm to the environment and their customers.’

It added that there was a ‘strong correlation’ between high spill levels and operational issues at their wastewater treatment sites, ‘which points to these companies not having properly operated and maintained their wastewater treatment works.’

It said the firms had failed to upgrade their assets where necessary, and had been slow to grasp their obligations to limit pollution from storm overflows.

A Yorkshire Water spokesperson said the firm is ‘disappointed’ with the proposed fine and that it had ‘co-operated fully’ with the investigation.

The spokesperson pointed to a £180 million plan to reduce sewage discharges before April 2025 and said: “We will be responding to the notice by September 10.”

Ofwat chief executive David Black stressed that the burden of £168 million of fines on the three water firms will fall on investors, rather than customers.

He said it is ‘not at all’ the case that the penalties on Thames Water, Yorkshire Water and Northumbrian Water will result in higher bills.

He said: “We set the rules on what charges they can recover from customers, so we make absolutely no provision for fines in the levels of bills that is set for customers.

“Customers can be reassured these fines sit with investors, not with customers of the water companies.”

Environment Secretary Steve Reed said: “The unacceptable destruction of our waterways should never have been allowed – and it is right that those responsible for illegally polluting our rivers, lakes and seas face the consequences.”

Ofwat said more than two-thirds of Thames Water’s wastewater treatment works with Flow to Full Treatment (FFT) permits had capacity and operational issues, while one in six of its storm overflows were found to be in breach of regulations.

Yorkshire Water’s wastewater treatment works were in better shape, with just 16 per cent of them having operational issues.

But 45 per cent of its storm overflows were in breach.

And 3 per cent of Northumbrian Water’s wastewater works had issues, while 9 per cent of its storm overflows were in breach.