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Polluted by sewage 1,854 times in 2025 lasting 17,322 hours - That's 2 years!
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Donate NowHere are all the reported sewage overflow totals for Monmouthshire 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 | Mounton Brook | Pwllmeyric SPS (CSO) | 193 | 3,932 | 94.7 |
| Dwr Cymru Welsh Water | River Usk | USK STW GRAIG OLWAY FARM LLANGVIEW | 87 | 1,453 | 99.9 |
| Dwr Cymru Welsh Water | River Wye Estuary | Chepstow South SPS Hunger Pill STW | 110 | 1,439 | 99.9 |
| Dwr Cymru Welsh Water | River Usk | LLANGYBI STW LLANGYBI USK | 234 | 1,345 | 99.9 |
| Dwr Cymru Welsh Water | Usk River | GOYTRE SEWAGE TREATMENT WORKS NANT | 93 | 1,275 | 99.9 |
| Dwr Cymru Welsh Water | River Honddu | PANDY STW PANDY MONMOUTHSHIRE | 92 | 1,073 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | CSO at Welsh Street Chepstow | 130 | 1,054 | 99.9 |
| Dwr Cymru Welsh Water | River Clydach | Maesygwartha SPS and CSO | 92 | 1,031 | 99.8 |
| Dwr Cymru Welsh Water | Clawdd Brook | CSO at Great Oak STW | 44 | 580 | 99.9 |
| Dwr Cymru Welsh Water | River Usk | ABERBAIDEN STW BEHIND HOP YARD FARM | 113 | 578 | 99.9 |
| Dwr Cymru Welsh Water | Clydach River | CLYDACH CSO | 61 | 545 | 99.8 |
| Dwr Cymru Welsh Water | River Usk | LLANFOIST WASTEWATER TREATMENT WORKS ME | 65 | 502 | 99.9 |
| Dwr Cymru Welsh Water | Mynachdy Brook | Bryn Y Gwenin SPS Abergavenny | 35 | 467 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | MONMOUTH STW REDBROOK ROAD MONMOUTH | 43 | 435 | 99.8 |
| Dwr Cymru Welsh Water | River Wye Estuary | Chepstow North Fairfield SPS | 75 | 332 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | Tintern Main SPS | 20 | 326 | 99.9 |
| Dwr Cymru Welsh Water | River Usk | Mill Street Screens CSO Abergaven | 69 | 263 | 99.6 |
| Dwr Cymru Welsh Water | Mounton Brook | Mathern SPS | 17 | 142 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | Monmouth 2 CSO | 38 | 140 | 100 |
| Dwr Cymru Welsh Water | Berthin Brook | Little Mill CSO, Panty Pwdin | 32 | 131 | 95.8 |
| Dwr Cymru Welsh Water | River Wye Estuary | Chepstow North SPS The Back | 59 | 72 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | Thornwell Road CSO | 49 | 63 | 99.9 |
| Dwr Cymru Welsh Water | River Monnow | CSO at Monmouth Town Pumping Station | 23 | 38 | 99.8 |
| Dwr Cymru Welsh Water | River Clydach | Glangrwyney Rd CSO, Gilwern | 28 | 31 | 99.5 |
| Dwr Cymru Welsh Water | Nant Y Wilcae | RAGLAN STW CHEPSTOW ROAD RAGLAN | 24 | 30 | 99.9 |
| Dwr Cymru Welsh Water | Nant Wilcae | Raglan CSO No. 1 | 7 | 16 | 98.6 |
| Dwr Cymru Welsh Water | Rivr Wye | WARREN SLADE SEWAGE PUMPING STATION | 1 | 7 | 99.9 |
| Dwr Cymru Welsh Water | River Wye | Raglan Way CSO | 12 | 7 | 99.9 |
| Dwr Cymru Welsh Water | Olway Brook | RAILWAY COTTAGE CSO | 1 | 3 | 99.9 |
| Dwr Cymru Welsh Water | River Severn Estuary | Magor SPS Magor STW Site Newport | 7 | 2 | 99.9 |
| Dwr Cymru Welsh Water | River Severn Estuary | Caldicot SPS at Caldicot STW | 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