Thames Water’s plans for a £3.6 billion “super-sewer” look set to come under heavy criticism in a new report due to be published later today.

The report by the Thames Tunnel Commission, an independent body set up by Hammersmith & Fulham Council and chaired by Lord Selbourne, former chairman of the Lords committee on science and technology, has taken evidence from a range of experts in recent months.

 The Council is spearheading a campaign against the plans for the increasingly controversial tunnel which is intended to reduce the number of discharges of untreated sewage in the river from 60 times a year to four or fewer.

The latest statement issued by the Council says:

“Thames Water stands to make a colossal £162million a year in additional revenue from its 20 mile long super sewer due to a ‘perverse incentive’ in the way the water industry is financed.”

According to Professor Colin Green of Middlesex University, a national expert on water economics, current industry regulations encourage water companies to build their way out of problems rather than consider greener, more sustainable options.

Professor Green says financial gain is likely to be the real motive behind the controversial scheme and that 14 million Thames Water customers will be ‘ripped-off’ under the current plans as the current price system ‘creates a strong incentive to pour concrete’ rather than explore green alternatives that don’t make money.

Under current regulations water companies are allowed to borrow money cheaply on the bond markets to pay for projects like the £3.6 billion Thames Tunnel - but water regulator Ofwat allows Thames Water to charge customers 4.5% per annum to service its borrowing and to pay dividends to its shareholders.

“The current system encourages water companies to borrow money to spend on large capital projects,” says Professor Green. “There is a strong incentive to pour concrete as for every pound Thames Water borrows, to pay for large projects like sewers or reservoirs, they make a handsome return off their customers.”

According to the Council, at a recent hearing of Lord Selborne's Thames Tunnel Commission evidence was presented showing that the Thames Tideway Strategic Study Group spent just £12,000 researching green alternatives to make the Thames cleaner - compared to more than £5million building a case for the super sewer.

Cllr Stephen Greenhalgh, H&F Council Leader, commented:

“Water industry experts are lining up to say that Thames Water’s case for the super sewer is flawed. The Thames has won awards for its cleanliness but we all agree that it could be cleaner still. The question is how this is delivered and it appears Thames Water’s true motivation for pushing through this massive concrete tunnel has more to do with financial gain than cleanliness.”