Water companies say they will also set aside more than £4bn to fund social tariffs – discounted bills for vulnerable people – over the next five years.

But the Consumer Council for Water (CCW), which represents bill payers, said support did not go far enough, as about 2.5 million households were already in debt to their water company.

“These rises will heap considerable pressure on millions of customers who are already having to make difficult choices,” said CCW chief executive Mike Keil.

“Customers want to see investment in improving services and cleaning up our rivers but that can’t come at an unbearable cost to struggling households.”

The CCW said this was the largest rise in water bills since the privatisation of the water industry 36 years ago.

David Black, chief executive of Ofwat, said: “We have pushed companies to double the amount of support over the next five-year period and strongly encourage customers who are struggling to pay their water bills to contact their water company to access this.

“While bills are rising, the £104bn investment we have approved over the next five years will accelerate the delivery of cleaner rivers and seas and help to secure long-term drinking water supplies for customers.”