Water companies across England and Wales are asking for bills to be made even higher than they first requested, with one company seeking an 84% hike.
The biggest water company in the UK, Thames Water, is now looking for bills to rise 53% and cost £667 a year by 2029/30, according to figures published by water regulator Ofwat.
It would make them the most expensive water bills in the country.
The biggest rise – 84% – is sought by Southern Water.
Of all 11 English and Welsh water and wastewater firms only one utility, Wessex Water, is not seeking even higher bills than they first requested from the regulator in July.
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Ofwat will make its final decision for how much water bills can rise on 19 December. Its interim decision, made in July, said the average bill could rise 21% a year.
On average the companies want bills to rise 40% and cost £615 a year by 2030, compared to the current average bill of £439 a year.
The rise comes as the government announced increased regulation on firms and three companies were hit by Ofwat with millions of fines. It was these demands that necessitated higher bills, the companies told Ofwat.
Under government proposals, water company executives could face prison time for failing to cooperate or obstruct investigations and be banned from taking bonuses. Greater compensation payments to those affected by contaminated water have also been proposed.
Companies also have to have their spending and investments approved by Ofwat.
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But the regulator said it “made it clear that companies needed to provide better evidence” to justify high spending allowances to show the proposed schemes were efficient, the best option and required.
The companies face hefty costs to clean up sewage-contaminated waterways but have a public outraged by effluent outflows and are unwilling to pay more for their service.
Thames Water faces a funding crisis as it described itself as “uninvestable” as it cannot pay dividends to shareholders and faces massive fines. It has defaulted on some of its £16bn debt pile.
A “full review” of the water sector has been announced by environment secretary Steve Reed with the aim of rebuilding a broken model to unlock “record” investment.