South West Water one of many firms warned about risks to supplies

A number of water companies in England - including a supplier in the South West of England - have been repeatedly warned about risks to their water supplies, documents from regulators and the Government show.

Ofwat, the Environment Agency and the Environment Department (Defra) notified 11 companies about security of supply risk concerns last year as part of the annual review of their water resources management plans, which cover the period from 2020 to 2045.

These were Thames Water, South East Water, Anglian Water, Affinity Water, Southern Water, South West Water, Cambridge Water, South Staffordshire Water, Portsmouth Water, Essex and Suffolk Water, and Albion Water.

The authorities raised concern over these companies' performance in areas ranging from leakages and chemical pollution to unsustainable abstraction from the environment and demand management.

It comes after the Government promised to introduce MOTs for water firms in a bid to prevent repeats of the situation that recently left thousands of South East Water customers in Kent and Sussex without supply.

South East Water blamed the recent outages on poor weather but the documents, uncovered by Watershed Investigations, show that regulators sent warnings for four years running about the pressure on its system.

In the most recent letter sent in November last year, they said the utility firm had "shown significant resilience concerns during dry weather with supplies being restricted due to high demand".

Ten other companies have also been told to address risks to shortages, most several times, with regulators sending South West Water, Southern Water, South Staffordshire Water and Portsmouth Water warnings over six consecutive years.

In one letter, the officials told Southern Water that it had persistently underperformed on its water resources management plan delivery, including leakage reduction, over the last six years.

"This has put both customer supply security and the environment at unacceptable risk," it read.

To South West Water, the regulators shared concerns over its management of high demand for water in the area, saying this has "contributed to operational challenges and your ability to meet customer demand during warm, dry periods.

"This requires immediate additional action to get customer demand down."

Thames Water was similarly warned that falling behind on demand management would increase the risk to security of supply for customers in a dry year in the short term, and to the firm veering offtrack on its long term ambitions to reduce demand.

To Anglian Water, and Essex and Suffolk Water, regulators shared their concerns that supply limits in some of their areas could hinder growth and sustainable development as potential new users are turned down.

James Wallace, chief executive of River Action, said: "This is yet more evidence that the UK is sleepwalking towards running out of water.

"It sounds absurd in a rainy country, but decades of under-investment and a profit-first model have left our water system - our lifeblood - dangerously fragile.

"Three million litres of drinking water are lost every day through leaking pipes and not a single new major reservoir has been built since privatisation in the late 1980s.

"The public has paid through rising bills - now water companies must invest to prevent taps running dry and serious damage to the economy, food security, industry and our health."

Last week, ministers outlined powers planned for a new watchdog as part of a major regulatory shake-up that aims to turnaround the troubled sector.

Under proposals published in the Water White Paper, the Government said water companies will have to perform health checks on their infrastructure to proactively identify crumbling pipes, pumps or issues at sewage treatment works before they fail.

An Ofwat spokesperson said: "While there has been progress, we have reminded those companies that remain off track that they will be held to account for any non-delivery of more resilient water supplies.

"We do not hesitate to act where they fail to do so, such as our ongoing enforcement investigations against South East Water on supply issues and customer service.

"We allocated £2 billion to companies to accelerate work on 30 major supply projects in our 2024 Price Review - itself an unprecedented £104 billion package to help companies deliver better outcomes for customers and the environment."

A Defra spokesperson said: "Water supply disruptions like those seen recently in the South East are entirely unacceptable.

"These failures cannot continue to happen.

"That is why this Government's Water White Paper sets out long-term, systemic reforms that will prevent these issues from happening again."

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