Philip Dunne MP, Chair of the House of Commons Environmental Audit Committee is calling for the water companies to double their investment in water treatment.

The EAC Chair was commenting in an interview on the Radio 4 Today news programme this morning on footage the BBC has seen of what looks like raw sewage being discharged into the River Thames in Oxfordshire.

Philip Dunne said:

"They’ve invested around a billion pounds a year since privatisation - it was about half that level prior to privatisation – and it’s still not enough. We’re dealing with a drainage network with hundreds of thousands of kilometres of pipework, much of which was installed over a hundred years ago. So the system is creaking and hasn’t kept pace with the development above ground over the last 60 years or so.”

The discharge was seen coming from an overflow pipe from Thames Water’s Cassington Sewage Treatment Works. Local campaigners have told the BBC that the water company could be in breach of its permit - the BBC witnessed the Windrush Against Sewage Pollution filming the overflow pipe last week and has also seen footage recorded in mid-December.

BBC interviewer Martha Carney said that this week the BBC revealed data suggesting that water companies in England and Wales have illegally discharged sewage thousands of times over the last four years.

Philip Dunne told the BBC he was “not surprised” and it was clear that there are thousands of sewage overflow systems and water treatment systems which are routinely discharging either partially treated, or in some cases, untreated sewage into the river systems.

Thames Water - "we regard all discharges of untreated sewage as unacceptable”

Commenting in a statement, Thames Water said:

“Cassington Sewage Treatment Works has not discharged untreated sewage since March 2021. An assessment on January 17^th found the river area was in good health. Any problem seems to be occurring in the long pipe that takes the treated effluent to the river.

"We are determined to understand what is coming out of the pipe and we regard all discharges of untreated sewage as unacceptable.”

The BBC invited Environment Minister Rebecca Pow for her reaction to the footage - the Minister told the broadcaster:

"If that is the case, that is completely unacceptable and if it's coming from what's called a storm sewage overflow, those facilities are to be used only in cases of extreme emergency."

She went on to say that if it was an illegal spill, “action needs to be taken and the Environment Agency will do that.”

The Environment Agency told the BBC that their major investigation into possible unauthorised spills at thousands of sewage treatment works is ongoing.

Water UK, which represents all the UK water companies, told the BBC that the companies agree that there is an urgent need for action to tackle the harm caused to the environment by overflows.

Philip Dunne “very hopeful” Government would adjust Ofwat’s priorities to allow water companies to invest more

Philip Dunne explained that the Government now have an opportunity to change this – they are about to publish their guidance to Ofwat for the next round of capital expenditure. The EAC chair said he was “very hopeful” the Government would adjust Ofwat’s priorities to allow water companies to invest more to stop the spillages from happening, commenting:

”We’d like them to increase the priority given to water treatment. I’d like to see them spending roughly double what they’re spending at the moment”

He added that one of things that would change the understanding and awareness of the regulator was the introduction by the Government of a requirement into the Environment Act which became law two months ago for water companies to install monitoring devices to test for water quality upstream and downstream of outfall pipes.