Water firms face legal action over sewage pollution

The UK's six biggest water firms are facing legal action over claims they underreported pollution and overcharged customers.

Severn Trent is the first in line, with claims against the other firms expected in the coming months.

A law firm says it could result in customers on average receiving £40 each, but the process could take years and there is no guarantee of success.

Trade body Water UK said the accusations were "without merit".

The claims are being brought by Professor Carolyn Roberts, an environmental and water consultant represented by Leigh Day Solicitors. Leigh Day says it is the first environmental collective action of its kind.

The legal basis of such action is fairly new, dating from 2015. No cases have reached a conclusion yet although a number are currently going through the courts, including against MasterCard and BT.

Thames Water, United Utilities, Anglian Water, Yorkshire Water and Northumbrian Water are all set to have cases brought against them after Severn Trent. If all prove successful, the law firm says 20 million customers could be eligible for compensation.

The claims are being brought on an opt-in basis, which means all water bill payers are automatically part of it unless they actively choose not to be.

The Competition Appeal Tribunal will first need to decide whether the claims can go ahead. That process can take around a year.

Professor Roberts said that she had watched "with horror" the rising number of stories of raw sewage being dumped into rivers and seas.

"It appears that because of the serial and serious under-reporting at the heart of these claims, water companies have been avoiding being penalised by [the regulator] Ofwat," she said.

"I believe this has resulted in consumers being unfairly overcharged for sewage services."

She added she believed the UK population had "a right to expect" rivers and seas would be clean.

However, a Water UK spokesperson called the claim "highly speculative" and "entirely without merit".

"The regulator has confirmed that over 99% of sewage works comply with their legal requirements. If companies fail to deliver on their commitments, then customer bills are already adjusted accordingly," the spokesperson said.

A Severn Trent spokesperson also called the claim "highly speculative with no merit" and said it strongly refuted it.

"Should pollutions ever occur, they are always reported to the Environment Agency. Any claim to the contrary is wholly and completely wrong.

"Our regulators, the Environment Agency and Ofwat, set strict targets and performance measures that deliver for our customers and the environment."

A number of water firms have been criticised over raw sewage discharges.