The West Country’s biggest water users are turning to their disused china clay pits and repurposing them to create additional water sources.

Photo: A disused China clay pit that now holds water for use elsewhere

The 2022 drought in Cornwall and parts of Devon was a warning that new, smarter ways to use water and reduce demand must be found to adapt to a changing climate.

According to the Environment Agency, arguably the biggest reduction of water use has been made in the counties’ china clay sector, with advice leading to a massive 99.5% reduction in the amount of water taken from the River Fal.

Five years ago, Imerys Minerals abstracted 2 billion litres of water a year from the freshwater river abstraction point, requiring significant pumping costs, to transport wet clay through its pipe network.

As a result of advice from the EA and Imerys’ actions, the firm has saved significant carbon and electricity costs and reduced this abstraction to about 10 million litres per year– less than 1% of its original drain upon freshwater sources.

Instead of a river, the water now comes from the company’s disused china clay pits which are so large they are visible on aerial maps, with some nearly rivalling the size of Cornwall’s largest reservoirs.

The pits have filled with a mixture of rain and ground water which is now used by the company instead of river water.

In addition, the EA says that taking and treating groundwater from water sources in three former china clay pits is helping to supply the water in customers’ taps in Cornwall.

Farmers in the region are also moving away from river and groundwater abstraction and finding ways to collect their own rainwater. One farm in Cornwall produces 15% of England’s seedlings used to grow brassica vegetables like broccoli, cabbage and cauliflower.

The farm had previously relied on multiple abstraction licences for this water-intensive activity.

Following advice from the Agency it has now invested in ways of storing rainwater to grow the brassica seedlings. This includes collecting water from its own polytunnels roofs and creating a clay-lined reservoir which will store 24 million litres of rain water.

‘Water is precious’

Clarissa Newell of the Environment Agency said:

“Water is a precious resource, so it is great to see by-products of Devon and Cornwall’s industrial past being turned into new water sources.

“Farmers are also investing in new ways of getting water which will pay them back. This is the way forward.

“The two biggest challenges for water are climate change and population growth. Only by finding smart ways to reduce our water demand can we protect the environment and in turn ourselves.”

Climate change is already starting to alter the water in rivers, lakes and groundwater. By 2050, the amount of water available could be down by 10-15%, with some rivers seeing 50-80% less water during the summer months.

The Environment Agency said the alterations, on top of the demands faced by a growing population, and the additional pressures of agricultural pollution, wastewater discharges and urban pollution are all combining to exacerbate water stress, commenting:

“In order to protect and enhance the environment, we will need to change how we abstract water. Water companies will need to change their abstractions and will need to find new sources of water.”