Top of the Poops | Place | Tre-gwyr | Polluted by Dwr Cymru Welsh Water

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Totals for Tre-gwyr in 2025

8 Sites polluted by Dwr Cymru Welsh Water

420 sewage dumps

1,952 hours duration

That's 2.71 months. On average 1.2 times a day

Change Over Time

Constituency for Tre-gwyr

Nearby Constituencies

Waterways in Tre-gwyr

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Pollution Summary 2025

Here are all the reported sewage overflow totals for Tre-gwyr 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 Lliw	Pont-y-cob Road CSO	120	1,028	98.3
Dwr Cymru Welsh Water	Loughor Estuary	GOWERTON WwTW	49	361	99.9
Dwr Cymru Welsh Water	River Lliw	KINGSBRIDGE CSO GORSEINON SWANSEA	58	210	99.9
Dwr Cymru Welsh Water	River Llan	CSO, Denver R’D Into Culvert Swansea	89	150	99.9
Dwr Cymru Welsh Water	River Lliw	CSO APX 70YDS U/S R'WAY B'GE U	43	134	80.4
Dwr Cymru Welsh Water	River Llan	CSO BRYNMOR RD SOC11 GOWERTON S124	39	47	99.7
Dwr Cymru Welsh Water	Surface Water Sewer Draining To Gors-Fawr Brook	CSO at Junction of Brithwen Rd & Swansea Rd	20	18	79.6
Dwr Cymru Welsh Water	Loughor Estuary	Cefn Stylle P.S. Gowerton	2	0	99.9
Dwr Cymru Welsh Water	River Llan	Kingsway CSO	0	0	85

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.

Analysing sewage pollution by the Water Industry

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© 2020-2025 Top-Of-The-Poops CC-BY-SA 4.0,
© Openstreetmap contributors, Contains OS data © Crown copyright and database right 2021-2025,
Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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