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Dorking and Horley - Live Sewage

Polluted by sewage 3,245 hours in 2026 , monitoring offline 169 hours so far..

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Contains OS Data © Crown copyright & database right 2021-2024
© Top of the Poops 2021-2024

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View Annual Sewage Data

You're looking at the totals that we have calculated for sewage in Dorking and Horley so far for 2026. It is an estimate, based on very poor quality live data from the Water Companies. The water companies report their sewage to the Environment Agency every year in April. You can see the last reported year in the other page

What's a potential overflow? If the CSO goes 'Offline' while its Overflowing, we don't know if it stopped overflowing until we get a 'Stop' event.

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Constituencies near Dorking and Horley

Daily Data

Jan - 1,935 hours
Feb - 1,218 hours
Mar - 84 hours
Apr - 7 hours
May - 0 hours , 169 offline
Jun - 0 hours
Daily data is experimental and data is not guaranteed to be accurate. Please inform us of any issue, we will fix.
Please note: We don't have rainfall data for Wales. If you know where to source it please let us know!
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Totals so far

Company Site Name Receiving Waterway Overflow Days Total Duration (hours) Offline/Potential Pollution
Thames Water Holmwood STW Holmwood Stream 45 863h -
Thames Water Ironsbottom STW River Mole 36 671h -
Thames Water Horley (Surrey) STW Mole 39 590h 15m -
Thames Water Dorking STW River Mole 27 427h -
Thames Water Charlwood, surrey Mans Brook 20 206h 45m -
Thames Water Stonebridge sso, brockham River Mole 28 202h 15m -
Thames Water Canfold Wood (Ewhurst) SPS Thornhurst Brook 10 80h 30m 67 h
Thames Water Brockham Bridge XX SPS River Mole 8 49h 30m -
Thames Water Boxhill SPS Into Land 14 42h 30m -
Thames Water Capel SPS Deanoak Brook 16 40h 30m -
Thames Water Castle Gardens (Dorking) SPS Mole 5 34h 45m -
Thames Water Ockley Road (Ewhurst) SPS Cobbler'S Brook 4 13h 102 h
Thames Water Commonside (Leatherhead) SPS Bookham Brook 3 11h 45m -
Thames Water Spooks hill, north holmwood Tanners Brook 2 5h 30m -
Thames Water Salfords SPS Salfords Stream 1 4h 15m -
Thames Water River Lane (Leatherhead) SPS Mole 1 1h 15m -
Thames Water Dean Oak Lane (Leigh) SPS Deanoak Brook 1 1h 15m -
Thames Water Canfold Wood (Ewhurst) SPS Thornhurst Brook 0 0h -
Thames Water Horley (Surrey) STW Mole 0 0h -
Thames Water Dorking STW River Mole 0 0h -
Thames Water Salfords SPS Salfords Stream 0 0h -
Thames Water Castle Gardens (Dorking) SPS Mole 0 0h -
Thames Water Ironsbottom STW River Mole 0 0h -
Thames Water Commonside (Leatherhead) SPS Bookham Brook 0 0h -
Thames Water Brockham Bridge XX SPS River Mole 0 0h -
Thames Water Holmwood STW Holmwood Stream 0 0h -
Thames Water Charlwood, surrey Mans Brook 0 0h -
Thames Water Spooks hill, north holmwood Tanners Brook 0 0h -
Thames Water Capel SPS Deanoak Brook 0 0h -
Thames Water River Lane (Leatherhead) SPS Mole 0 0h -
Thames Water Boxhill SPS Into Land 0 0h -
Thames Water Stonebridge sso, brockham River Mole 0 0h -
Thames Water Ockley Road (Ewhurst) SPS Cobbler'S Brook 0 0h -

Data Sources & Accuracy

EDM (Event Duration Monitoring) data and Consented Discharges to Controlled Waters with Conditions from Environment Agency & Data Map Wales, and Scottish Water

Experimental derived data from Thames Water API, Some data may be missing or inaccurate. Live sewage data from Stream Water API

Uses Environment Agency rainfall data from the real-time data API (Beta) - Rainfall data is delayed by up to two days.

This website is intended to provide an accurate representation of the Environment Agency data. The data is hard to use, and thus some errors may have been made. If you find something that is incorrect, please raise an issue at the GitHub issues page and we'll endeavour to fix it quickly.

This project is not associated, approved or endorsed by any of the companies whose logos you see here.

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Analysing sewage pollution by the Water Industry

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