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Polluted by sewage 411 times in 2025 lasting 4,872 hours
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Donate NowHere are all the reported sewage overflow totals for Dorking and Horley in 2025. Sometimes sewage can be being dumped for months at a time.
Reporting refers to how much of the time the monitoring was active. In this constituency all the declared CSO Combined Sewage Overflow - a device that, when operating, pours combined rainwater & sewage into a waterway s appeared to have monitoring enabled for more than 50% of the year
| Company | Waterway | Site | Sewage Dumps | Duration (Hours) | Reporting % |
|---|---|---|---|---|---|
| Thames Water | River Mole | IRONSBOTTOM (SIDLOW) WWTW | 70 | 1,095 | 99.9 |
| Thames Water | Burstow Stream | BURSTOW STW, HATHERSHAM ROAD, SMALL | 72 | 1,040 | 99.4 |
| Thames Water | Mole | LEE STREET | 59 | 835 | 86.5 |
| Thames Water | Holmwood Stm Leigh Brk | HOLMWOOD SEWAGE TREATMENT WORKS | 61 | 819 | 99.9 |
| Thames Water | River Mole | DORKING STW (STORM) | 23 | 296 | 99.2 |
| Thames Water | River Mole | COACH ROAD CSO ON STONEBRIDGE SEWER | 26 | 218 | 98.1 |
| Thames Water | Mans Brook | CHARLWOOD, SURREY | 25 | 166 | 92.2 |
| Thames Water | Thornhurst Brook | Canfold Wood | 13 | 82 | 99.6 |
| Thames Water | River Mole | Brockham Bridge | 8 | 71 | 100 |
| Thames Water | Deanoak Brook | CSO AT CAPEL SPS | 15 | 67 | 99 |
| Thames Water | Cobbler'S Brook | Ockley Road | 9 | 63 | 91.8 |
| Thames Water | Mole | CASTLE GARDENS SPS | 7 | 48 | 100 |
| Thames Water | Salfords Stream | SALFORDS SEWAGE PUMPING STATION | 7 | 29 | 100 |
| Thames Water | Into Land | Box Hill | 9 | 16 | 94.7 |
| Thames Water | Tanners Brook | SPOOKS HILL, NORTH HOLMWOOD, SURREY | 3 | 12 | 96.8 |
| Thames Water | Bookham Brook | Commonside | 2 | 5 | 99.7 |
| Thames Water | Mole | RIVER LANE PUMPING STATION, FETCHAM | 2 | 5 | 100 |
| Thames Water | Deanoak Brook | Dean Oak Lane | 0 | 0 | 100 |
| Thames Water | Tanners Brook | SURFACE WATER SEWER | 0 | 0 | 99.9 |
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.
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Get in touch if you have queries or want to discuss our data.
press [at] top-of-the-poops.org