16 million UK households could see water bill hiked to £627

Thames Water could raise bills to £627 a year to help fix leaks. The embattled water supplier has moved to promise to invest up to £3bn more over the next five years - but customers could face bills north of £600 amid the Cost of Living crisis.

Bills could rise as much as 44% under its most ambitious spending plans. Thames said on Monday it had been able to up its spending without increasing bills on top of the original forecasts “due to a rebalancing of operating and capital expenditures”.

The Thames Water chief executive, Chris Weston, said: “Our business plan focuses on our customers’ priorities. As part of the usual ongoing discussions relating to PR24, we’ve now updated it to deliver more projects that will benefit the environment. We will continue to discuss this with our regulators and stakeholders.”

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Mike Keil, the chief executive of the Consumer Council for Water, said: “On the surface the proposal for more investment from Thames Water is a positive step for its customers that have endured some of the worst customer service in the sector.

“We should not lose sight of the fact that only 16% of its customers thought the company’s proposed bill rises in its five-year plan were affordable. This announcement appears to offer nothing to ease the fears of those already struggling to pay.”

The Liberal Democrats’ Treasury spokesperson, Sarah Olney, said: “It would be an absolute disgrace if customers are forced to foot the bill for Thames Water’s shambolic failings. Ofwat cannot allow these bill hikes to go ahead.”

In the submission to Ofwat, the company said it was discussing its “green economy recovery” plan (GER) with the regulator. And Thames said extreme weather in 2022 had hurt the “achievability” of hitting its targets.

It is in dialogue with Ofwat over how it would “determine if we can proceed with the GER programme”. Thames Water currently services 16 million customers.