South East Water has been granted extended drought powers to cut water releases from Ardingly Reservoir as capacity drops to a critically low 17 per cent.

From today (Thursday, 22 October), South East Water will reduce the daily volume of water released from Ardingly Reservoir into the River Ouse following approval from the Environment Agency (EA) to extend its current Drought Permit powers.

By implementing this proactive intervention now, the drinking water company can retain vital reserves in the reservoir, significantly lowering the risk of customer and environmental impacts if dry conditions persist.

South East Water say they will closely monitor the gradual reduction of releases through its monitoring and mitigation plan which also includes river restoration which is resulting in stretches of the river being narrowed to minimise environmental impact.

Ardingly Reservoir stores roughly 4.77 to 8.3 billion litres of water (part of South East Water's primary supply network. (Image: EDDIE MITCHELL)

placeholder image — Ardingly Reservoir stores roughly 4.77 to 8.3 billion litres of water (part of South East Water's primary supply network. (Image: EDDIE MITCHELL)

John Halsall, South East Water CEO, said: “We are closely monitoring Ardingly Reservoir, which is currently less than 20 per cent full (17.1 per cent as of 18 October), and noticeably lower than it was at this time last year.

“Under this new agreement, we will reduce the rate of release in a managed, phased manner day-by-day.

“This stepped approach allows us to carefully monitor the River Ouse at every stage to minimise any environmental impacts, while maintaining an agreed minimum flow downstream of our Barcombe Water Treatment Works abstraction point to safeguard local habitats and wildlife.”

This measure builds directly on the initial Drought Permit granted by the Environment Agency on 29 September, which enabled the company to lower release rates to protect reservoir levels while maintaining public water supplies.

As of October 2026, the reservoir has fallen below 20% capacity (standing at approximately 19.4%) following hot summer conditions and the granting of an Environment Agency drought permit. (Image: EDDIE MITCHELL)

With rainfall forecast across the region this week and heading into November, water levels are expected to begin a gradual recovery. The flexible solution agreed with the Environment Agency will directly support and accelerate that recovery process.

John Halsall added: “This is one of many measures we’re taking to protect water supplies and the environment across Sussex. We have deployed more teams than ever to find and fix leaks, adapted our operational network, and introduced key conservation measures to help reduce the demand for water.

“We are hugely grateful to all our customers who have already reduced their water use. We continue to closely monitor the situation and adapt our network to keep water flowing for everyone.”

Richard O’Callaghan, Environment Planning Manager of the Environment Agency, said: “The level of drought we are seeing in parts of the country is something we have not experienced for decades and we are stepping up our oversight and planning to protect public supplies in affected areas.

“The drought permit sets out a series of firm conditions that cut the risk of harm to the environment while supporting the public water supply at Ardingly Reservoir.

“South East Water must closely monitor the gradual reduction of flows from the reservoir every step of the way and take immediate action to address any impact on the environment.

”We are asking everyone to use less water, which will leave more water in the rivers and the environment which will help wildlife and nature.”