Farmland has the potential to store millions of litres of water per hectare in the soil to manage supply and prevent flood risk.
Work to hold back water in whole farm reservoirs was undertaken by Essex and Suffolk Water to demonstrate benefits to farms, the ecology of the landscape, public water supply and flood risk.
The work explored which elements and zones in the landscape of a farm could hold water and, with proper management, release it when needed. By using geographical features such as shallow aquifers and gravel seams beneath the surface, between six and ten million litres of water were stored per hectare in a farm’s soil.
The Whole Farm Reservoir study, carried out with the Environment Agency and Atkins, explored problems of insufficient and excessive water on agricultural land.
It showed that farm-scale, nature-based solutions can help tackle two major challenges of climate change – summer droughts and winter flooding.
Emily Brown, environmental scientist at Atkins, said the trial at Spains Hall Estate in Essex to use the whole farm as a store for water had to be compatible with its wider ecological plan.
“The results of the initial study were extremely encouraging with a 5-10% increase in river flows during the summer months, where there would normally be drought,” Brown said. “In winter, the measures could lower the risk of local flooding by between 15-30%.”
Atkins looked at the patterns of river flows and rainfall throughout the year, as well as traditional farm ponds and shallow aquifers. It showed gravel seams beneath the surface acted like natural sponges for the landscape.
Brown said the nature-based approach could be rolled out across the country to provide greater resilience in the UK’s water supply and flood risk management efforts.
The farm at Spains Hall has undertaken a transition towards a more sustainable land-use model, so was keen to be involved in how water resources were impacted by its activity.
Archie Ruggles-Brise, estate manager at Spains Hall said: “Numbers are key, if we want to optimise our system to benefit the farm and the wider environment we need to know which actions are likely to have the greatest reward.
“We need those numbers to engage with other sectors, without them farms are too easily discounted as irrelevant by drought and flood professionals.”