A key utilities company which supplies water to millions of homes in Kent has been hit with fines after "serious failures" in its sewage treatment sites.

An investigation carried out by water services regulation authority, Ofwat, revealed Southern Water's failures to manage vital assets used to clean and treat wastewater which have a direct impact on the environment.

Southern Water says it is "deeply sorry" and will now pay customers £123m over the next five years plus a £3m fine for its failings.

WATCH: Southern Water's chief executive, Ian McAulay apologises

The money will be returned to people via bill rebates over the next five years.

Each customer will receive at least £17 in 2021 and at least £11 per year for the following four years, totalling £61.

A report published by Ofwat said: "Southern Water has deliberately misreported data and failed to make provision for effectually dealing with and treating wastewater."

In November 2017, Southern Water discovered serious irregularities in the way the sampling of its wastewater treatment works were being carried out, which led to an internal investigation.

Employees, including senior managers, were deliberately preventing samples being taken to check compliance.

"We have clearly fallen far short of the expectations and trust placed in us by our customers and the communities we serve...” Ian McAulay

This meant its true performance was hidden from Ofwat and the Environment Agency.

Ofwat added: "This has led to spills of wastewater which has not gone through all of the processes it is supposed to before being released into the environment.

"The company now recognises it has failed but had it not taken steps to put things right, including engaging Ofwat on its reparations package, we would have been minded to impose a greater penalty."

Ian McAulay, Southern Water’s chief executive, said: “We are deeply sorry for what has happened. There are no excuses for the failings that occurred between 2010 and 2017, outlined in the report.

"We have clearly fallen far short of the expectations and trust placed in us by our customers and the communities we serve.”

“In 2017 I was brought in to drive change and transformation. Since then we have been working very hard to understand past failings and implement the changes required to ensure we better deliver for our customers and meet the standards they deserve.

“There is a lot more work to do but we’re pleased this proposal agreed with Ofwat enables us to fully make amends to our customers and regain their trust as quickly as possible.”

The company is also subject to criminal investigations by the Environment Agency in relation to non-compliance with environmental permits.

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