Water companies have been warned that current levels of overflow discharges into rivers cannot continue.

The utility companies have been told to reduce pollution incidents by 30% by 2025 and to improve seven and a half thousand miles of river.

David Black, Interim Chief Executive of Ofwat, said: "The current levels of storm overflow discharges into rivers cannot continue, and the water sector must tackle this. Water companies have a critical role in protecting and preserving the natural environment.

"Customers and the public rightly expect water companies to take this role extremely seriously, and there has been widespread, understandable frustration and anger. Addressing storm overflows must take place alongside wider actions to improve rivers to good ecological status."

Ofwat also backed investment of around £1 billion every year for water companies to improve the natural environment by increasing the capacity of the wastewater system to meet growing demand. In July, it approved almost £3 billion extra for green recovery plans to deliver lasting environmental improvements.

A recent article in The Mail revealed that nine of the country's biggest water companies - many foreign owned - had built up a debt mountain of more than £50 billion.

An Ofwat spokesperson said: "Ofwat protects customers' interests by challenging companies to take steps where necessary to improve their financial resilience - such as by reducing gearing or by reducing dividends to retain equity in the business. This approach ensures companies do not gain from tax benefits that would otherwise arise from excessive gearing levels.

"Companies taking on higher gearing carry the risk themselves but must share any benefits with customers. We continue to monitor and challenge companies where we see gaps in their identification and management of financial risk."

Punchline Gloucester approached local water company Severn Trent - a UK stock market-listed company - for a comment.