Thames Water returns to profit after raising bills
But the firm says it only has enough debt funding to keep the business going until the end of 2026.
Thames Water has returned to a full-year profit after hiking its customers' bills by 40% last year.
The UK's largest water company reported post-tax income of £113m for the 12 months to the end of March, swinging from a £1.51bn post-tax loss the previous year.
However, the firm's net debt also swelled to £18.5bn from £16.8bn as it said it only had enough debt funding to keep the business going until the end of 2026.
The publication of Thames Water's results comes after the government rejected a proposed rescue deal for the business in June, pushing the firm one step closer to nationalisation.
Under the terms of the deal, Thames' lenders wanted leniency from future pollution fines in return for writing off £9.4bn of its debt pile and investing new money.
Thames Water said on Wednesday pollution incidents had fallen by 18%. It hit just over half of its performance targets.
The firm said it was below target when it came to customer complaints, which jumped by 77% to 122,798 in a year.
Bill complaints made up over three quarters of the total and doubled compared to the previous year.
The results also reveal how money from its customer bills is not enough to fund the massive upgrades needed to improve its aging and historically underinvested infrastructure, which means it needs to borrow more money.
The firm said debt had risen as it "continued to fund the business through... debt and internally generated cash flows".
He told Reuters on Wednesday that its lenders "want to see what the new Burnham government thinks before providing more funding".
Labour MP Andy Burnham is expected to become Prime Minister on Monday. He has previously called for Thames Water to be nationalised.
Dr Heather Smith, a senior lecturer in water governance at Cranfield University, said a "possible outcome" for Thames Water was "a special administration regime, which is sort of a temporary public control".
"That's not the same as full nationalisation," she added, saying it could be used if the business goes bust "but just to get it to a new buyer".
"Long-term nationalisation, I think, would be a struggle because I think the costs of what we need for infrastructure upgrades are such that it would be a real struggle for the public purse to handle – more so than the private sector."
Elsewhere in the financial results, Thames Water reported that Weston's pay had risen by £128,000 to £1.163m from £1.035m.
Weston did not receive a bonus, but the firm paid out £4.1m in bonuses to other directors, up from £2.8m the previous year.
Environment Secretary Emma Reynolds said: "It's outrageous that one of the worst-performing water companies is handing out bonuses and inflation-busting pay rises to its executives."
"It flies in the face of basic fairness, and the British public are right to be furious. We've banned bonuses for polluting water bosses and will be taking action to prevent bonuses by any other name."
Additional reporting by Simon Jack
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