Media Queries
Get in touch if you have queries or want to discuss our data.
press [at] top-of-the-poops.org
Please Support Us
We rely on donations to fund our work. Please support us if you can
Polluted by sewage 2,976 hours in 2025 , monitoring offline 1,256 hours
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.
Your local MP is Chris Hinchliff (Labour) - Find out more about their interests, donors, and voting at They Work For You
Thank you so much to everyone who contributed to the site in 2025 to keep it running. We do rely on
your contributions! Developing and running a website costs real money.
Please consider a one-off or small recurring donation.
| Company | Site Name | Receiving Waterway | Overflow Days | Total Duration (hours) | Offline/Potential Pollution |
|---|---|---|---|---|---|
| Anglian Water | SHENFIELD SEWER SSO | River Wid | 54 | 646 h 12m | - |
| Thames Water | Cottered STW | Cottered Brook | 32 | 539 h 15m | - |
| Anglian Water | BARLEY STW | Fowlmere Stream | 40 | 530 h 45m | - |
| Anglian Water | LETCHWORTH-NORTON COMMON SSO | Pix Brook | 28 | 512 h 17m | - |
| Thames Water | Weston STW | Weston | 30 | 370 h 30m | - |
| Thames Water | Barkway STW | River Quin | 7 | 93 h | - |
| Thames Water | Weston STW | Weston | 8 | 90 h 45m | - |
| Thames Water | Therfield STW | River Rib | 12 | 68 h 15m | 721 h |
| Thames Water | Cottered STW | Cottered Brook | 6 | 54 h 15m | - |
| Anglian Water | BALDOCK-NORTON ROAD SP | Onto Land | 5 | 28 h 12m | - |
| Thames Water | Standon STW | Rib | 3 | 12 h 30m | - |
| Thames Water | Chapmore End STW | Rib | 7 | 9 h 45m | - |
| Thames Water | Buntingford STW | River Rib | 3 | 5 h 15m | - |
| Anglian Water | BARLEY STW | Fowlmere Stream | 5 | 5 h 12m | 270 h |
| Anglian Water | LETCHWORTH-NORTON COMMON SSO | Pix Brook | 1 | 5 h 7m | - |
| Anglian Water | ASHWELL STW | River Rhee | 8 | 4 h 51m | - |
| Thames Water | Chapmore End STW | Rib | 0 | 0 h | - |
| Anglian Water | SANDON (NEW) STW | Cat Of River Ivel | 0 | 0 h | - |
| Thames Water | Barkway STW | River Quin | 0 | 0 h | - |
| Thames Water | Buntingford STW | River Rib | 0 | 0 h | - |
| Anglian Water | Letchworth WRC | Pix Brook, River Gt Ouse | 0 | 0 h | - |
| Thames Water | Therfield STW | River Rib | 0 | 0 h | 264 h |
| Anglian Water | BALDOCK-NORTON ROAD SP | Onto Land | 0 | 0 h | - |
| Thames Water | Standon STW | Rib | 0 | 0 h | - |
| Anglian Water | ASHWELL STW | River Rhee | 0 | 0 h | - |
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.
Get in touch if you have queries or want to discuss our data.
press [at] top-of-the-poops.org