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Polluted by sewage 1,158 times in 2025 lasting 8,891 hours - That's 1.03 years!
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Donate NowHere are all the reported sewage overflow totals for Montgomeryshire and Glyndwr 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 % |
|---|---|---|---|---|---|
| Dwr Cymru Welsh Water | River Twymyn | Commins Coch Pumping Station CSO | 120 | 2,675 | 99.9 |
| Dwr Cymru Welsh Water | River Iaen | LLANBRYNMAIR STW LLANBRYNMAIR | 95 | 1,855 | 94.4 |
| Dwr Cymru Welsh Water | Wye River | LLANGURIG STW | 75 | 1,476 | 99.9 |
| Dwr Cymru Welsh Water | Garsiwn Ditch | MACHYNLLETH STW CSO | 65 | 460 | 98.7 |
| Dwr Cymru Welsh Water | Dyfi | MACHYNLLETH STW | 55 | 410 | 98.6 |
| Dwr Cymru Welsh Water | River Dee | CEFN MAWR WwTW | 48 | 318 | 99.9 |
| Dwr Cymru Welsh Water | River Goch | Pant CSO | 73 | 313 | 99.9 |
| Dwr Cymru Welsh Water | River Aber Glesyrch | Ceinws SPS | 20 | 197 | 99.8 |
| Dwr Cymru Welsh Water | Tref Y Nant Brook | CEFN PS | 46 | 157 | 99.5 |
| Dwr Cymru Welsh Water | Glanyrafon Brook | Rhostyllen Bersham Colliery CSO | 52 | 145 | 99.5 |
| Dwr Cymru Welsh Water | River Goch | Afon Eitha CSO | 52 | 88 | 98.9 |
| Dwr Cymru Welsh Water | Garsiwn River Dovey | Machynlleth - Doll Street CSO | 62 | 86 | 99 |
| Dwr Cymru Welsh Water | River Ceiriog | DOL Y WERN - CSO | 32 | 69 | 99.6 |
| Dwr Cymru Welsh Water | River Eitha | Penycae SPS | 17 | 66 | 99.9 |
| Dwr Cymru Welsh Water | Tref Y Nant Brook | Cefn Monsanto CSO | 28 | 58 | 99.5 |
| Dwr Cymru Welsh Water | Black Spool | Johnstown Combined Sewerage System CSO | 32 | 55 | 99.9 |
| Dwr Cymru Welsh Water | River Goch | Bersham Colliery CSO | 36 | 53 | 99.9 |
| Dwr Cymru Welsh Water | River Bradley | CHIRK PS (SCREENED STROM) | 24 | 52 | 99.8 |
| Dwr Cymru Welsh Water | Eitha | Ruabon PS | 20 | 51 | 99.9 |
| Dwr Cymru Welsh Water | Unnamed Watercourse | Fford Offa CSO | 31 | 48 | 99.2 |
| Dwr Cymru Welsh Water | River Dyfi | MACHYNLLETH WWTW (STORM OUTFALL) | 9 | 47 | 99.3 |
| Dwr Cymru Welsh Water | River Dee | Chirk O/S 24 Offa St CSO | 14 | 45 | 99.6 |
| Dwr Cymru Welsh Water | River Ceiriog | Glynceiriog Y Gammer - CSO | 45 | 33 | 98.7 |
| Dwr Cymru Welsh Water | Eitha | Ruabon Paddock Row CSO | 7 | 20 | 96.9 |
| Dwr Cymru Welsh Water | Glanyrafon Brook | CSO at COLLIERY ROAD RHOSTYLLEN | 19 | 19 | 99.7 |
| Dwr Cymru Welsh Water | Black Brook | Aberderfyn CSO, Rhosllanerchrugog | 13 | 18 | 84.4 |
| Dwr Cymru Welsh Water | River Dee | Rhosymedre Park Rd CSO | 11 | 16 | 99.2 |
| Dwr Cymru Welsh Water | River Laen | CSO at Llanbrynmair STW Llanbrynmair | 3 | 14 | 100 |
| Dwr Cymru Welsh Water | River Dee | Newbridge SPS | 7 | 14 | 99.7 |
| Dwr Cymru Welsh Water | Garsiwn Ditch | Heol Penrallt CSO | 14 | 8 | 99.9 |
| Dwr Cymru Welsh Water | Un-Named Watercourse | Machynlleth - Popular Road CSO | 21 | 7 | 91.1 |
| Dwr Cymru Welsh Water | River Dee | CSO at Rear Hamden Way Plas Madoc | 4 | 1 | 99.6 |
| Dwr Cymru Welsh Water | River Eitha | Penycae West End School Field Land CSO | 5 | 1 | 99.5 |
| Dwr Cymru Welsh Water | River Ceiliog | DOLYWERN STW | 2 | 1 | 99.9 |
| Dwr Cymru Welsh Water | Unnamed Flowing To Bradley Brook | Chirk Chapel Lane CSO | 1 | 0 | 96.3 |
| Dwr Cymru Welsh Water | River Bradley | CHIRK PS (SCREENED STORM) | 0 | 0 | 99.8 |
| Dwr Cymru Welsh Water | River Goch | CSO at Ruabon Combined Sewerage System | 0 | 0 | 99.9 |
| Dwr Cymru Welsh Water | River Twymyn | LLAN LLANBRYNMAIR PS CSO | 0 | 0 | 99.9 |
| Dwr Cymru Welsh Water | Garsiwn Ditch | MACHYNLLETH STW | 0 | 0 | 98.7 |
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