Ardingly Reservoir at record low: drought permit granted, but it's not a fix
South East Water has been given permission to take less water from a river tributary to prop up a West Sussex reservoir sitting at under a quarter full – but even the regulator says this alone won't solve the problem.
What’s actually happened
The Environment Agency has granted South East Water a drought permit covering Ardingly Reservoir, near Haywards Heath in West Sussex. The reservoir, which supplies 280,000 customers, was sitting at just 23% of total capacity on 28 September – the lowest level recorded for this point in the year.
The permit itself is narrow and specific. It allows the water company to leave less compensation water flowing into the River Ouse at Barcombe Mills, and to release less water to top up the Shell Brook tributary. In plain terms: the reservoir gets a bit of breathing room, and the river downstream gets a bit less water than it normally would.
What the permit does and doesn’t do
This is not a drought declaration, and it’s not a fix. The Environment Agency has been explicit that the permit “will not be enough to improve security of water supply” on its own. South East Water is expected to take further steps under its drought plan, which could include scrapping exemptions in its current temporary use ban and moving to a non-essential use ban – a tougher restriction than the hosepipe-style bans most people are familiar with.
So the headline here isn’t “crisis averted”. It’s closer to “one small lever has been pulled, and more may follow if the weather doesn’t cooperate.”
So who is actually affected, and who isn’t
If you’re one of South East Water’s 280,000 customers served by Ardingly Reservoir, this is relevant to you, though not yet in a way that changes your taps. No wider restrictions have been imposed by this permit alone; it governs river flows, not household supply.
Anyone downstream on the River Ouse, or with an interest in the Shell Brook tributary’s ecology, is more directly affected by the mechanics of the permit itself, since less water will be released into both. The Environment Agency says it will be “staying alert for any impacts on the environment” and has promised to hold the company to the conditions attached.
For everyone else in the UK, this is a local story about one reservoir, not a national drought announcement.
What happens next
The Environment Agency’s own language puts the real stakes on the coming winter, not on this permit. Richard O’Callaghan, the agency’s Environment Planning Manager, said at least average winter rainfall is needed to refill Ardingly Reservoir and move Sussex “out of drought and into recovery by spring.” If rainfall comes in below average, he says pressure on water resources will continue – which reads as code for further restrictions becoming more likely, not less.
For context, the Met Office’s October outlook is currently forecasting average rainfall and temperatures. That’s a forecast, not a guarantee, and it covers one month out of the several needed to meaningfully refill a reservoir this depleted.
The takeaway
This is a genuine, checkable regulatory decision – a specific permit, tied to specific river-flow conditions, issued because a specific reservoir is unusually low. What it isn’t is evidence that supply restrictions are imminent for customers, or that the drought is “solved.” The Environment Agency has said as much itself: this permit buys time, not security. Whether tougher measures follow depends on how much it rains between now and spring, something no permit can control.