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Polluted by sewage 1,249 times in 2025 lasting 12,747 hours - That's 1.48 years!
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Donate NowHere are all the reported sewage overflow totals for Vale of Glamorgan 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 Ewenni | Ewenni No 2 Pumping Station | 141 | 3,008 | 99.9 |
| Dwr Cymru Welsh Water | River Thaw | COWBRIDGE STW COWBRIDGE VALE OF GLA | 137 | 2,088 | 99.9 |
| Dwr Cymru Welsh Water | River Ely | COSLECH STW PETERSTON SUPER ELY | 118 | 1,263 | 99.7 |
| Dwr Cymru Welsh Water | Llandow Brook | Llandow SPS | 67 | 1,207 | 99.4 |
| Dwr Cymru Welsh Water | Stembridge Brook | Llysworney SPS | 51 | 910 | 81.8 |
| Dwr Cymru Welsh Water | Unnamed The | TRERHYNGYLL PS WEST OF JANE HODGE H | 40 | 752 | 99.8 |
| Dwr Cymru Welsh Water | Bristol Channel - Breaksea Pt | ABERTHAW WWTW W ABERTHAW BARRY | 41 | 608 | 99.9 |
| Dwr Cymru Welsh Water | Nant Ganna | Treoes Main SPS | 30 | 537 | 99.8 |
| Dwr Cymru Welsh Water | An Nant Dyfrygi | Ystrad Owen PS Vale Of Glamorgan | 21 | 340 | 99.9 |
| Dwr Cymru Welsh Water | River Thaw | East Orchard Castle CSO | 30 | 275 | 99.8 |
| Dwr Cymru Welsh Water | Severn Estuary | LLANTWIT MAJOR WWTW (STW) WICK ROAD | 37 | 246 | 99.95 |
| Dwr Cymru Welsh Water | River Ely | Whitebridge PS Peterston Super Ely | 29 | 242 | 99.9 |
| Dwr Cymru Welsh Water | North West Corner Of Barry | BARRY DOCKS PS CSO OFF WIMBOURNE RD | 188 | 219 | 99.8 |
| Dwr Cymru Welsh Water | Nant Ganna | Llangan (NR Bridgend) SPS | 37 | 100 | 99.8 |
| Dwr Cymru Welsh Water | Coldbrook | COLDBROOK ROAD EAST 1 BARRY | 5 | 96 | 99.7 |
| Dwr Cymru Welsh Water | Bristol Channel | BARRY TWN PS LSO ISLAND CAR PARK | 49 | 89 | 99.9 |
| Dwr Cymru Welsh Water | Coldbrook | COLDBROOK RD EAST 2 BARRY | 7 | 87 | 99.5 |
| Dwr Cymru Welsh Water | River Thaw | Castileton Wood CSO, Barry | 22 | 87 | 99.9 |
| Dwr Cymru Welsh Water | Bristol Channel | FONTYGARY SPS AND LOWER FONTYGARY S | 9 | 79 | 99.9 |
| Dwr Cymru Welsh Water | Bristol Channel | Rhoose SPS | 13 | 67 | 99.2 |
| Dwr Cymru Welsh Water | River Ely | PETERSTON SUPER ELY STW CSO MAIN AV | 17 | 62 | 99.9 |
| Dwr Cymru Welsh Water | River Weycock | Weycock Cross SPS | 7 | 46 | 99.9 |
| Dwr Cymru Welsh Water | Wrinstone Brook | WENVOE SEWAGE PUMPING STATION | 13 | 40 | 99.9 |
| Dwr Cymru Welsh Water | Coldbrook | DANIEL STREET CSO DANIEL STREET | 8 | 37 | 99.9 |
| Dwr Cymru Welsh Water | Barry Brook | CWM BARRY SPS PORTHKERRY PARK | 10 | 34 | 99.4 |
| Dwr Cymru Welsh Water | Nant Talwg | NANT TALWG PS BARRY | 6 | 31 | 91.1 |
| Dwr Cymru Welsh Water | River Ewenny | EWENNY P.STN. NO. 1 EMERGEN | 5 | 30 | 99.9 |
| Dwr Cymru Welsh Water | Highway - Colwinston Brook | Storm Overflow and Emergency Overflow at Colwinston Pumping Station | 5 | 23 | 99.9 |
| Dwr Cymru Welsh Water | Whitelands Brook | A SEWAGE PS PORTHKERRY SPS ASSET NO | 2 | 21 | 99.9 |
| Dwr Cymru Welsh Water | Coldbrook | MERTHYR DYFAN ROAD CSO BARRY | 11 | 21 | 99.8 |
| Dwr Cymru Welsh Water | Coldbrook | FOOTPATH R/O WESTBURY CLOSE BARRY | 11 | 18 | 99.9 |
| Dwr Cymru Welsh Water | Bristol Channel | BARRY TOWN PS ISLAND CAR PARK BARRY | 10 | 15 | 99.1 |
| Dwr Cymru Welsh Water | Cold Brook | Whitewell Road CSO 2, Barry | 24 | 11 | 99.8 |
| Dwr Cymru Welsh Water | River Thaw | Graig Penllyne SPS | 2 | 8 | 99.9 |
| Dwr Cymru Welsh Water | Rhoose Brook | Station Rd CSO, Rhoose | 3 | 6 | 93.8 |
| Dwr Cymru Welsh Water | Nant Talwg | WESTWOOD RISE PUMPING STATION | 4 | 5 | 99.9 |
| Dwr Cymru Welsh Water | Barry Dock No1 | A COMBINED SEWER OVERFLOW DYFRIG ST | 5 | 4 | 99.6 |
| Dwr Cymru Welsh Water | River Cadoxton | ATLANTIC TRADING EST PS BARRY , | 1 | 3 | 100 |
| Dwr Cymru Welsh Water | Barry Brook | A COMBINED SEWER OVERFLOW PONTYPRID | 8 | 3 | 100 |
| Dwr Cymru Welsh Water | Barry Harbour | BARRY TOWN PS (EMER) ISLAND CAR PK | 2 | 2 | 100 |
| Dwr Cymru Welsh Water | Coldbrook | Barry - Coldbrook Road East CSO | 4 | 2 | 99.6 |
| Dwr Cymru Welsh Water | Coldbrook | WHITEWELL ROAD CSO 1 BARRY | 5 | 2 | 100 |
| Dwr Cymru Welsh Water | Barry Dock No 1 | HOLTON ROAD CSO HOLTON ROAD | 4 | 1 | 99.9 |
| Dwr Cymru Welsh Water | Coldbrook | PRICE AVENUE CSO BARRY | 3 | 1 | 99.2 |
| Dwr Cymru Welsh Water | Wrinstone Brook | WENVOE CSO STATION ROAD EAST | 3 | 1 | 81.5 |
| Dwr Cymru Welsh Water | Barry Brook | COLCOT ROAD/CLAUDE ROAD ASSEST NO | 2 | 0 | 100 |
| Dwr Cymru Welsh Water | Barry Old Harbour | BARRY ISLAND PS | 1 | 0 | 99.8 |
| Dwr Cymru Welsh Water | Bristol Channel | Fonmon Park SPS, Rhoose | 1 | 0 | 100 |
| Dwr Cymru Welsh Water | Coldbrook | BARRY BRIDGE STREET CSO BARRY | 0 | 0 | 100 |
| Dwr Cymru Welsh Water | Unnamed Watercourse Then Pumping Station Then Barry Docks | CSO at BARRY - ST HILLARY RISE (REAR) | 0 | 0 | 96.9 |
| Dwr Cymru Welsh Water | Bristol Channel | KNAP PS BARRY VALE OF GLAMORGAN | 0 | 0 | 99.9 |
| Dwr Cymru Welsh Water | Barry Old Harbour | KNAPP SEWAGE PUMPING STATION BARRY | 0 | 0 | 99.7 |
| Dwr Cymru Welsh Water | River Colhuw | Llantwit Major SPS | 0 | 0 | 100 |
| Dwr Cymru Welsh Water | Nant Talwg | NANT TALWG WAY PUMPING STATION | 0 | 0 | 99.9 |
| Dwr Cymru Welsh Water | River Thaw | SPS Millfield Drive Cowbridge | 0 | 0 | 99.9 |
| Dwr Cymru Welsh Water | Tredogan Stream | Tredogan SPS | 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
Annual figures up to and including 2025 come from official water company returns. The 2026 figure is our own estimate, derived continuously from the companies' live data feeds.
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