South East Water applies for Drought Order in Sussex to protect drinking water supplies

South East Water has today (Friday 10 October) applied to the Secretary of State for Environment, Food and Rural Affairs for a Drought Order to help conserve the remaining water stored within its Ardingly Reservoir and protect drinking water supplies in Sussex.

Following the driest spring in England 1893, the lack of rainfall has put significant pressure on drinking water supplies, particularly in the Sussex region.

South East Water’s Ardingly Reservoir serves 228,000 customers in Haywards Heath and the surrounding areas in Sussex and currently stands at 27.6 per cent full. As a result, the drinking water company was granted a Drought Permit by the Environment Agency on Monday 22 September, which allows South East Water to vary the conditions of its abstraction licence.

South East Water, which has 2.3 million customers across Kent, Sussex, Surrey, Berkshire and Hampshire, has already taken a number of actions to reduce pressure on its water resources, including fixing leaks, moving water around the network, injecting water into the network and putting in place a hosepipe ban in Kent and Sussex. While these measures have had an impact, the exceptional weather conditions mean more action is needed to protect customer drinking water supplies and the environment for as long as possible.

South East Water’s Head of Water Resources, Nick Price, said: “This year has been exceptionally dry, and the River Ouse catchment in Sussex has only experienced two years (1976 and 1893) with lower spring and summer rainfall in its 155 year rainfall record. Consequently the River Ouse, where we take water from in Sussex for supply and to refill our Ardingly Reservoir, is running low.

“Therefore we are applying to the Secretary of State for Environment, Food and Rural Affairs for a Drought Order to help conserve the remaining water that is stored within our Ardingly Reservoir.

“We are working closely with our regulators and following our Drought Plan which sets out the steps we take during periods of low rainfall. We would like to thank our customers who have also helped, by being mindful of their water use where possible, and appreciate their support in keeping demand down.

“To conserve as much water as possible we are also planning to remove some of the exemptions currently in place as part of our Temporary Use Ban, or hosepipe ban, for customers in Sussex. This action will come into effect on Friday 17 October.”

Further information can be found here: southeastwater.co.uk/tubs-sussex.

Customers can find out more about water saving advice by visiting southeastwater.co.uk/save-water.

Editor's notes:

Ardingly Reservoir level

Ardingly Reservoir levels can be found here. Since mid-June the reservoir has been dropping steadily and currently stands at 27.6 per cent full*.

Although high rainfall was experienced at the beginning of September, cumulative rainfall between March 2025 and August 2025 in that area of Sussex has been around 63 per cent of the long term average.

To fill Ardingly Reservoir at least 80 per cent of average rainfall is needed from now until February 2026 - this is not currently forecast.

The River Ouse rises near Lower Beeding in West Sussex and flows eastward into East Sussex before heading southward to Newhaven where it meets the sea. The main river is 35 miles long, passing through Lewes and skirting Haywards Heath, and forming the central element of a vast network of smaller streams, with the River Uck being its primary tributary.

*27.6 per cent is the total capacity figure and represents the volume of water in the reservoir. This is different from the usable capacity figure, which is the volume that can practically be abstracted. This figure is lower due to the structure and location of the drawoff tower as the pump intakes aren't located in the very bottom of the reservoir which impacts the amount of water that can be abstracted. Natural build up of sediment at the bottom of the reservoir is another factor that reduces the amount of water that can be used.

What is a Drought Permit?

A Drought Permit allows South East Water to vary the conditions of its abstraction licence. South East Water was last granted a drought permit by the Environment Agency in 2022.

The Drought Permit granted on 22 September allows South East Water to change the way it operates the reservoir in two ways; water can be abstracted from River Ouse to refill the reservoir earlier and the compensation release from the reservoir to the Shell Brook can be reduced. By supporting the refill of Ardingly Reservoir over the winter the permit will help keep taps flowing for customers and reduce the risk of impacts on the environment.

What is a Drought Order?

A Drought Order is similar to a Drought Permit in that it allows amendments to be made to abstraction licences when there has been an exceptional shortage of rain. Both water companies and the Environment Agency (in England) can apply to the Secretary of State for Environment, Food and Rural Affairs for a Drought Order to manage water resources for water supply and environmental benefit.

South East Water’s Drought Plan

South East Water’s Drought Plan sets out the steps it would take during periods of low rainfall and high demand to ensure it can deliver a reliable water supply for the essential needs of drinking, washing, cooking and cleaning.

South East Water’s latest Drought Plan was published in 2022 and was consulted upon at the time. You can read that Drought Plan here.

It details what actions it would take to conserve water and secure customers’ supplies, while balancing the needs of the environment.

These actions include:

• Moving water around its network
• Fast-tracking schemes to increase water resources
• Working even harder to fix leaks
• Promoting sensible water use
• The introduction of temporary water use restrictions (commonly known as hosepipe bans)

To ensure drought plans are up-to-date South East Water reviews them every five years and publishes a draft document for consultation.

How many people does Ardingly Reservoir serve?

Ardingly Reservoir supplies 228,000 customers in the Haywards Heath area of Sussex.

When was Ardingly Reservoir built?

Ardingly Reservoir was built in 1978.

Temporary Use Ban/Hosepipe ban

The exemptions that are being removed on 17 October for customers in Sussex include:

• Watering new lawns at domestic premises
• Watering trees, whips, saplings and hedges planted before the ban and within the last three years
• Watering food crops at domestic premises or private allotments

If South East Water previously wrote to customers to explain they were exempt from the hosepipe restrictions, this will end and they will no longer be able to use their hosepipe.

If they were not exempt but activities they were doing were covered by an exemption, this will also now end.

This will mean the only time where a hosepipe can be used is for health and safety purposes only.

Further information can be found here: southeastwater.co.uk/tubs-sussex

What is South East Water doing to address the water shortage?

South East Water has fast-tracked several projects to:

• Make sure water can move more easily around its network
• Take the pressure off existing supply sources
• Transfer more water into Sussex

For example, a new pipeline connecting treated water from Bewl Water Reservoir in Kent to the East Sussex network will soon be active. This will move water between the counties for the first time, giving South East Water greater resilience and flexibility and allows it to move water from areas with a good supply to those that need it more.

How is South East Water tackling leaks?

South East Water is actively working to reduce the number of leaks across its supply area, fixing leaks 21 per cent quicker than last year. Over the last year South East Water has repaired over 18,000 leaks on its network - an increase of 12 per cent on the three-year average - 6,000 customer-side leaks, 900 of which were free leak repairs for customers on its Priority Services Register.

South East Water currently spends around £40 million a year fixing and finding leaks across its network and this is increasing.

Between April and 24 September 2025, in Sussex South East Water has repaired 2,354 leaks, an increase of 14 per cent on last year. During August and September, across the county, it has repaired 787 leaks.

South East Water is making Sussex its priority and has also increased the number of staff out finding and fixing leaks in Sussex to the highest number it has ever had.

Boosting resilience in Sussex

South East Water is in the final stages of a multi-million-pound investment project to create a more resilient water supply network within Wealden, Sussex.

In a direct response to recent incidents, South East Water has invested more than £12 million installing approximately 17 kilometres of new pipeline between its water treatment works at Bewl and its drinking water storage tanks at Wadhurst and Rotherfield. The new pipeline has been laid and is currently being tested before being brought into service in October.

Along with upgrades to its Bewl Water Treatment Works, this project will enable South East Water to move water between Kent and Sussex for the first time, giving greater resilience and flexibility in the future, which will allow the drink water company to maintain customer supplies more readily during unexpected disruptions.