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Polluted by sewage 769 times in 2025 lasting 3,977 hours
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Donate NowHere are all the reported sewage overflow totals for Porth 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 place 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 Rhondda | Brook Street Combined Sewer Overflow | 149 | 1,099 | 99.9 |
| Dwr Cymru Welsh Water | Rhondda Fawr | Station Rd CSO, Dinas, Porth | 120 | 919 | 95.8 |
| Dwr Cymru Welsh Water | River Rhondda | A COMBINED SEWER OVERFLOW GYFEILLON | 132 | 657 | 99.9 |
| Dwr Cymru Welsh Water | Rhondda Fawr River | CSO GYLFACH ROAD PORTH RHONDDA | 94 | 420 | 99.9 |
| Dwr Cymru Welsh Water | River Rhondda Fach | CSO at CROSS STREET YNYSHIR R-C-T | 99 | 348 | 99.9 |
| Dwr Cymru Welsh Water | River Rhondda Fach | Aberrhondda Road CSO | 62 | 247 | 98.3 |
| Dwr Cymru Welsh Water | River Rhondda | A Combined Sewer Overflow, Trehafod | 13 | 152 | 94.5 |
| Dwr Cymru Welsh Water | River Rhondda | CSO AT CADWGAN TERRACE TREHAFOD | 16 | 41 | 99.9 |
| Dwr Cymru Welsh Water | River Rhondda | Trehafod Pumping Station | 51 | 39 | 99.9 |
| Dwr Cymru Welsh Water | River Rhondda Fach | CSO at Wattstown-Bailey St Land Recla | 15 | 35 | 71.1 |
| Dwr Cymru Welsh Water | River Rhondda Fach | James Terrace CSO | 8 | 10 | 99.9 |
| Dwr Cymru Welsh Water | River Ely | CSO at Penrhiwfer Ashdale Rd CSO, rear of No23 | 6 | 4 | 99.8 |
| Dwr Cymru Welsh Water | River Rhondda | Cymmer Rd CSO, Porth | 4 | 1 | 100 |
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