Enter your postcode to find the storm overflow outfalls nearest your home — how close they are, how often they discharged, and what that means for your area.
Free · No signup · Official EDM annual return data · England & Wales
storm overflow outfalls within 5km of your home
| Distance | Watercourse | Company | Spills | Duration (hours) | Permit ref |
|---|
Distances are straight-line. Proximity to an outfall doesn't measure exposure — discharges enter the named watercourse and flow downstream.
Storm overflows affect rivers and the environment — not your tap water. Drinking water comes from a separate, treated supply system. Want to know what's actually coming out of your tap?
Check your tap water quality →Storm overflows are designed to release a mixture of rainwater and untreated sewage into rivers and the sea during heavy rainfall, to prevent sewage backing up into homes and streets. They are legal, but their frequency of use has become highly controversial. Environmental campaigners and regulators argue that many overflows are being used far too often — not just during genuine storms but during normal rainfall.
Storm overflows do not affect your tap water. Drinking water is supplied through a completely separate treated network. Overflow discharges affect the environmental quality of rivers, lakes and coastal waters.
Coverage: England and Wales. English EDM annual returns are published by the Environment Agency; Welsh returns are published by DŶr Cymru Welsh Water and Hafren Dyfrdwy (Natural Resources Wales does not publish them in an open format). Scottish and Northern Irish equivalents aren't yet available openly.
Storm overflow data: Event Duration Monitoring (EDM) annual returns reported by water companies. England: published by the Environment Agency at environment.data.gov.uk. Wales: DŶr Cymru Welsh Water and Hafren Dyfrdwy annual returns, compiled by The Rivers Trust — © DŶr Cymru/Welsh Water, © Hafren Dyfrdwy. All under the Open Government Licence v3. Postcode geocoding by postcodes.io. Explore water company open data at streamwaterdata.co.uk.