Trefynwy

Polluted by sewage 104 times in 2025 lasting 614 hours

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Totals for Trefynwy in 2025

3 Sites polluted by Dwr Cymru Welsh Water

104 sewage dumps

614 hours duration

Sewage pollution map of Trefynwy — Sewage pollution map of Trefynwy: 614 hours in 2025

That's 3.65 weeks. 2 times a week, on average

Change Over Time

Constituency for Trefynwy

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Waterways in Trefynwy

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Pollution Summary 2025

Here are all the reported sewage overflow totals for Trefynwy 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 Wye	MONMOUTH STW REDBROOK ROAD MONMOUTH	43	435	99.8
Dwr Cymru Welsh Water	River Wye	Monmouth 2 CSO	38	140	100
Dwr Cymru Welsh Water	River Monnow	CSO at Monmouth Town Pumping Station	23	38	99.8

Data Sources & Accuracy

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.

Top of the Poops

Analysing sewage pollution by the Water Industry

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Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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