THAMES Water must put the environment 'higher on its agenda' after it was fined £2 million for pouring sewage into a West Oxfordshire brook, a top Environment Agency figure has said.

The agency's lead investigator Robert Davis said a 'catalogue of failings' from the water giant meant untreated sewage was discharged from the Bruern Road Sewage Pumping Station at Milton-under-Wychwood on or before August 9, 2015.

Sewage polluted a 50m stretch of the Idbury Brook, near Milton-under-Wychwood, killing 146 Bullhead fish, and flooded a nearby garden.

The company was sentenced at Oxford Crown Court on Friday, just 21 months after a record £20m fine for a similar offence.

Mr Davis also said it was the 126th time the Environment Agency and its predecessor, the National Rivers Authority, had prosecuted Thames Water for sewage pollution since the water industry was privatised in 1989.

He said: "Cases like this have a really serious impact on people and wildlife.

"We want this to prompt companies to take more proactive action, maintaining to a high standard and investigating.

He added: "Previous actions have resulted in significant improvements from Thames Water.

"We don't want to have a repeat cycle. We hope this case pushes the environment higher up their agenda."

Thames Water misinterpreted more than 1,000 alarms at the pumping station in the months before the incident.

The company missed multiple chances to fix issues, leading to a 'complete failure' of the station and sewage seeping out into the brook.

Residents alerted the Environment Agency to the issue and Mr Davis revealed he himself 'waded along the stream bed picking up dead fish' back in 2015.

Thames Water launched a clean-up operation, and cleared up the garden straight away, but Mr Davis said the damage was already done.

He added: "If they had been operating the sewage pumping station to a higher standard then this never would have happened.

"The writing was on the wall building up to this incident.

"During that period they were taking a considerable risk with the environment."

The lead investigator added the water firm's large estate was not an excuse for failures that risked the environment.

He said: "They say it's inevitable they have problems - it's a big operation, but they have 15 million customers so they're well funded to comply with the law."

Thames Water was fined £2 million - roughly equivalent to its weekly profits - and ordered to pay costs to the Environment Agency of £79,991.57.

The company has since said it welcomes Judge Peter Ross's suggestion that £200,000 of the fine should go to three environmental charities in the Oxfordshire area.

Campaign group Windrush Against Sewage Pollution (WASP) was in court for the sentencing and welcomed the decision.

Founder Ashley Smith said: "The fine was big enough to get their attention.

"They can't afford to behave in the same way and really have to get a grip."

Since the incident in August 2015, Thames Water has not had a serious incident at any of its 4,780 pumping stations and Judge Ross acknowledged improvements to management and training had been made.

A Thames Water spokesperson said: “We operate almost 5,000 pumping stations and our customers rely on us to make sure they are all working properly, all the time.

“On this occasion in 2015, one didn’t and we’re really sorry about that.

"Since then, there has not been a single pollution at any of our pumping stations and we’re pleased the judge acknowledged our hard work and commitment in this area.

“We’ve reduced pollution incidents by 69 per cent since 2013 and have committed to reducing this by a further 18 per cent in our 2020-25 business plan.”