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Polluted by sewage 326 times in 2024 lasting 691 hours
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Here are all the reported sewage overflow totals for Porthmadog in 2024. 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 | Cyt Bach Surface Watercourse | SNOWDON STREET PS | 135 | 530 | 99.9 |
| Dwr Cymru Welsh Water | River Glaslyn | BORTH Y GES PS | 33 | 60 | 99.3 |
| Dwr Cymru Welsh Water | Un-Named Stream | PORTHMADOG - LOMBARD STREET SS | 84 | 28 | 98.6 |
| Dwr Cymru Welsh Water | River Glaslyn | BRITANNIA PS | 9 | 23 | 99.9 |
| Dwr Cymru Welsh Water | Nant Y Cyt | CHAPEL STREET/MADOG STREET PORTHM | 20 | 18 | 86.2 |
| Dwr Cymru Welsh Water | Stream Leading To Cyt Stre | TREMADOG SSO | 15 | 17 | 99.9 |
| Dwr Cymru Welsh Water | River Glaslyn | CSO at Porthmadog Borth-Y-Gest SPS | 25 | 12 | 99.4 |
| Dwr Cymru Welsh Water | River Glaslyn | AMMANDA TERRACE BORTH Y GEST PORTHM | 3 | 0 | 54.5 |
| Dwr Cymru Welsh Water | Nant Y Cyt | BAKERS LANE/CHANDLERS PLACE PORTH | 2 | 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.
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