Thames Water is formulating an updated business plan as the embattled water supplier continues to scramble for cash to stay afloat, according to reports.

The company, which is the UK’s biggest water firm serving 16 million customers, is reportedly drawing up a revised five-year spending plan, which could be published within days,

Members of the board are expected to meet today (Thursday, April 18) to approve the plan and executives hope to publish it on Friday, Bloomberg reported.

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In its original business plan, first unveiled in October, the utility company said it wanted to raise customer bills by 40 per cent to fund an investment programme worth £18.7 billion.

But it said water regulator Ofwat had imposed regulations on the plan which made it “uninvestable”.

It meant the funding crisis facing Thames Water deepened as investors pulled a £500 million emergency funding package that was due to be paid at the end of April.

Furthermore, the holding company behind Thames Water, Kemble Water Finance Limited, told creditors earlier this month it defaulted on some of its own debts after missing an interest payment.

Oxford Mail: Thames Water has been under pressure over its finances and sewage spills Thames Water has been under pressure over its finances and sewage spills (Image: Oxford Mail)Thames Water is reportedly preparing to approach lenders to fund the spending plans which means it could take out a new loan.

It has already been saddled with net debts of nearly £15 billion, while it has also come under intense scrutiny after missing sewage spill and leakage targets.

It needs the cash funding to drive its turnaround plan to meet performance targets for customers, the environment and other shareholders over the next few years.

Ofwat is scrutinising the plans and is due to publish its draft response in June.

Thames Water has previously stressed that it remains “business as usual” for the supplier, despite the financial difficulties.

The company declined to comment on the latest reports.

Thames Water is increasing sewage treatment capacity by 66 per cent at the Witney Sewage Treatment Works at a cost of over £17 million.

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The company said it will "improve the ability to treat the high volumes of incoming sewage and reduce the need for overflows during wet weather”. 

It comes as Thames Water has come under fire from open water swimmers in Oxford following an investigation by TV presenter Steve Backshall into a 12-hour spell of discharge into the river across the border in Buckinghamshire. 

The water company uses storm overflows to discharge excess waste and rainwater from its combined sewer system to nearby rivers and seas during periods of heavy rainfall.

The overflow helps to stop rainwater and sewage from overwhelming the pipe network and backing up into people’s homes and streets.

A Thames Water spokeswoman said: “Taking action to improve the health of rivers is a key focus for us and we are leading the way with our transparent approach to data.

“We remain the only water company to provide live alerts for discharges so our customers and environmental groups can then make informed decisions about swimming or carrying out activities in the rivers.  

“Pollutants, animal faeces from livestock and wildlife, along with run off from farms and roads can also contribute to hazards found in watercourses, which is why we’d recommend reading the Government’s advice on open water swimming.

“We have experienced excessive rainfall this winter, so our storm overflow system has worked to protect customers' homes during the wet weather, by releasing diluted wastewater into rivers, rather than letting it back up into people’s homes."