The Guardian reports water companies are at the centre of a major investigation by the financial and environmental watchdogs after they admitted they may have illegally released untreated sewage into rivers and waterways.

The Environment Agency and Ofwat said they had begun an investigation into sewage treatment works, after new checks led to the admission from the water companies.

This investigation will involve more than 2,000 sewage treatment works, nearly a third of the total number in England and Wales, with any company caught breaching their legal permits liable to enforcement action, including fines or prosecutions.