Several water companies came close to breaching their licences in order to maintain public water supply after the intense heat and dry weather last summer, Environment Agency (EA) documents show.

Obtained through a freedom of information request by Unearthed, Greenpeace’s investigative journalism unit, the documents show how the EA was worried about companies not having enough clean water with which to supply their customers.

The majority of reservoirs were “exceptionally low” by September, with some near to the point of being classed as “dead storage”, where the quality of the remaining water is so poor that treating it may not be possible.

Yorkshire Water helicoptered a temporary pipeline across a protected area so it could transfer water from one reservoir to another while Southern Water came close to reaching the legal limit it could abstract from a chalk stream.

Reservoirs in the South West were also critically low. One in particular, the Upper Tamar, would have emptied and “become unusable” without a drought permit, the EA said.

The region remains in drought status one year on with a hosepipe ban still in place across Cornwall and now parts of Devon, though this is set to lift at the end of September, South West Water said.

Campaigners believe the crisis to be a making of the water industry’s neglect of infrastructure with the Government failing to hold it to account.

Megan Corton Scott, political campaigner for Greenpeace UK, said: “With leaky infrastructure wasting up to a trillion litres of water a year and no new reservoirs built for decades, climate change could bring severe water shortages to the UK and once again this Government is playing fast and loose with the future of the country.”

The EA documents show how the agency was concerned that Yorkshire Water could potentially damage a protected natural area on the South Pennine Moors by transferring water from the Walshaw Dean Upper reservoir to Ponden reservoir in Worth Valley.

Levels in Worth Valley had dropped to below 28% of their capacity by last September and were forecast to fall by a further 20%.

Reservoir depleted
Baitings Reservoir in Ripponden, West Yorkshire, had almost emptied in August 2022 but had topped up again by March (Danny Lawson/PA)

Yorkshire Water said its actions ensured their was no interruption to people’s water supply and that it spoke with Natural England about not disturbing the South Pennine Moors during the water transfer.

A spokesperson said: “As a responsible landowner in the area, we completely understand the sensitivity of the South Pennine Moors and operate within these protected sites regularly so we used helicopters to help us transport and lay a temporary pipeline across the South Pennine Moors from Walshaw Dean reservoir to Ponden reservoir.”

Southern Water said it came close to breaching the legal limit of what it could abstract from the Tess and Itchen rivers in Hampshire because its allowance was tightened in 2019, meaning it had to apply for a drought permit late last summer.

This would have posed a risk to Atlantic salmon that use the river, according to the EA documents, though Southern Water said the permit was not needed in the end following autumn rain and so it was withdrawn.

A spokesperson said: “In 2022 as we saw river levels drop, we applied for a drought permit and did everything we could to reduce demand and protect the rivers including widespread water efficiency advertising and eventually the imposition of a temporary-use ban.

“In the event, levels on the river never dropped below the hands-off flow, no drought permit was needed and we withdrew our application.”

The EA warned South West Water that they would have to start providing bottled water and tanker trucks if the dry weather continued, the documents show.

They issued a drought permit to help South West Water refill the Colliford reservoir over the winter, which the agency described as a “strategic” reservoir for Cornwall and said there are “significant risks to security of supply next year” if the company does not use the drought permit.

A spokesperson for South West Water told Unearthed there had only been pressure at Colliford and that no one suffered loss of supply, while they strongly disagree with any suggestion of the company being unprepared.

An EA spokesperson said: “Last year’s summer was one of the hottest on record. The Environment Agency worked to provide timely advice to government, ensure water companies were implementing their drought plans and helping farmers to manage resources.

“Through the National Drought Group, we will always review what can be done to improve our future preparedness and strengthen our planning.”