The boss of a major water company has labelled her own company’s performance “unacceptable”.

The chief executive of Thames Water, Sarah Bentley, was answering questions from the Environmental Committee on Wednesday, October 13, around the ongoing issue of river contamination.

The committee’s inquiry into river water quality found that water companies discharged raw sewage into rivers in England more than 400,000 times last year, an issue that affects many of the rivers in Gloucestershire.

Ms Bentley said: “I can understand why people are genuinely upset and concerned about the quality of the rivers and the situation with sewage discharge into those rivers.

“A number of my colleagues have suggested making sure that we transparently share information about when those spills are occurring.

“More importantly, what I have heard in the year that I have been running Thames is that our customers just find spills unacceptable, and we find them unacceptable and I’m really committed to finding out how we can eliminate storm discharges so that people can swim confidently in the river.”

Ms Bentley said Thames Water was spending £1.2bn over the next five years on improving its overall network to treat sewage and rain and highlighted a number of measures she intends to take.

She added: “Since I joined 12 months ago I have been accelerating the money that we have got during this regulatory period.

“Our ageing infrastructure, whether that’s on the water side with leakage, or on the sewage network in terms of the capacity we are treating, needs addressing.

“When I started, I went out, I listened to our customers, I listened to environmental groups and members of this House, and of this committee, and it is clear that we have a broad range of performance metrics that we need to change”.

In Gloucestershire, work has now begun to tackle the issue which affects rivers such as the Windrush, which runs through Bourton-on-the-Water.

Campaign group, Windrush Against Sewage Pollution, have been calling for action for quite some time.

A spokesperson said: “Bourton on the Water is a busy tourist town yet the sewage works has not been adapted to deal with demand and common faults with leaky sewers mean that it has to dump untreated sewage it cannot handle, sometimes for months on end.”