A rare river providing clean drinking water to thousands of homes in Kent could run dry by 2050 unless decisive action is taken, campaigners have claimed.

The River Darent is a chalk stream river running from Dartford to Sevenoaks which serves water to thousands of homes in Darenth Valley, the south east and parts of London.

The clean water comes from chalk aquifers, an underground layer of rock fed solely by rainfall which also supports a river biodiversity of trout, voles, otters and kingfishers, as well as course fishing.

Campaigners from the Darent River Preservation Society (DRiPS) claim the future of the River Darent is under threat unless water companies reduce or end abstraction from chalk streams altogether.

They say the amount of water available could be reduced by 10-15% by 2050, with some rivers seeing 50% to 80% less water during the summer months.

Last week environmental officers were called to a section of the river close to the Riverside industrial estate in Dartford following reports of distressed fish.

An operations team later found a sluice gate, which is used to control the flow of the river, had been tampered with meaning water had flowed downstream into the tidal section.

DRiPs chairman Stuart Merrylees warned the waterway was already suffering from the effects of a very dry summer.

He said: "It’s been a very dry summer and the flow is really low at the moment.

"People just don’t realise the chalk aquifers under the river provide drinking water for tens of thousands and they are getting very low.

"We are getting worried the world at large is just unaware how critical the situation will become."

Chalk streams are extremely rare with most of the worlds found here in the south east.

In 1985 the River Darent was identified as one of ten UK rivers likely to disappear and DRiPS was formed in response.

Alongside South East Water and the National Rivers Authority (as the Environment Agency was then known), DRiPs devised the 'Darent Action Plan' in 1995 to rescue the disappearing Darent.

Its stated aim was to "maintain an environmentally acceptable flow in the River Darent" set at 50%.

Water companies reduced their groundwater abstraction to meet it and monitored the effects.

However investment in the plan tapered off and it officially came to an end in 2013.

There has been 18 months since September 2016 when the flow at Hawley, Dartford was below its threshold target.

DRiPs is concerned if we experience more dry winters and summers, and abstraction levels remain the same the river may completely run dry.

With the rapid expansion of new housing building projects in the area they claim water demand will soon outstrip supply.

They also point out there is no guarantee current water company licences won't return to abstraction levels of the late 1990s.

Former Defence Secretary and MP for Sevenoaks, Michael Fallon, has criticised Thames Water’s abstraction from the River Darent.

He backed the group's call for a reduction in chalk stream abstraction and requested OFWAT, the water regulator take a tougher stance.

He said: “At current levels, the Darent is set to run dry. That is even before you consider the nearly 24,000 new homes both Sevenoaks council and Dartford council have been instructed to build in the coming years.

"OFWAT must exercise greater control over unrestricted abstraction and hold companies like Thames Water properly accountable for their actions.

Last week he added: “Thames Water must commit to stopping abstraction that impacts on vulnerable chalk streams in order to ensure the Darent’s survival.

"The Darent is being sucked dry to provide water for London which wouldn’t be needed if Thames did much more to tackle leakage.”

Thames Water has acknowledged the South East is water­stressed and by 2045 predicts there will be a shortfall of 350 million litres per day due to population growth and climate change.

To deal with this they are planning measures including reducing leakage by 15%, installing an extra 700,000 smart meters, and building a new reservoir in Oxfordshire by 2037.

James Presland, media relations officer for Thames Water said: “We take the ecological importance of the River Darent seriously and understand local concerns for this and other chalk rivers.

“The Darent has been the focus of some of the most extensive measures to protect chalk streams implemented anywhere in the country and early indications show the river is now more resilient to drought and ecology has improved.

“There is little indication that further reductions in abstraction would provide any more significant improvements.

“We have committed that any extra water needed in the future to meet the needs of a growing population will be sourced from elsewhere. Ultimately, it’s our ambition to cease all abstraction that has an adverse impact on vulnerable chalk streams.”

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