The water firm, along with Northumbrian Water, South East Water, Southern Water and Wessex Water, will be allowed to raise an additional £463 million in revenue, short of the £2.7 billion they had asked for.

It is expected to result in an average increase of 2.2pc in bills for customers of the five firms, on top of the 24pc average hike they had already been granted by water regulator Ofwat.

Water bills will increase for customers across the region (Image: Rui Vieira/PA Wire)

This is less than the £556 million extra funding, equating to an average increase of 3pc to customer bills, that had been provisionally granted in October.

The Competition and Markets Authority (CMA) said it wanted to balance minimising the impact on people’s bills with the need for the suppliers to have enough funding for things such as their environmental and drinking water quality legal obligations.

The regulator decided some extra money was needed to support their investments, but the majority of their funding requests had been rejected.

Kirstin Baker, chairwoman of the independent group appointed by the CMA, said: “We’ve rejected most of the bill increases water companies asked for but allowed limited extra funding where that’s genuinely needed, balancing concerns about affordability with the need to secure our water supplies and cut pollution.

“A significant part of this extra money reflects market movements since Ofwat’s decision.”

The five companies had requested approval to raise more money through customer bills after arguing that Ofwat’s decision left them unable to meet the regulatory requirements set out for them.

This refers to a decision made in late 2024, when Ofwat said it would allow water firms to raise bills by an average of £157, or 36pc, over the next five years to help finance investment into crumbling infrastructure.

The amount that customer bills are going up varies between suppliers.

© Norwich Evening News