Top of the Poops | Waterway | River Tawe | Polluted by Dwr Cymru Welsh Water

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Totals for River Tawe in 2025

31 Sites polluted by Dwr Cymru Welsh Water

1,696 sewage dumps
11,834 h duration

That's 1.37 years. On average 4.6 times a day

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Constituencies along River Tawe

Places along River Tawe

Pollution Summary 2025

Here are all the reported sewage overflow totals for River Tawe in 2025. Sometimes sewage can be being dumped for months at a time.

Company	Waterway	Site	Sewage Dumps	Duration (Hours)	Reporting %
Dwr Cymru Welsh Water	River Tawe	TREBANOS Wastewater Treament Works	140	2,476	97.3
Dwr Cymru Welsh Water	River Tawe	Inco CSO Clydach Swansea	114	1,083	99.2
Dwr Cymru Welsh Water	River Tawe	CSO at Craig Y Duke Trebanos SOC	101	900	99.2
Dwr Cymru Welsh Water	River Tawe	CSO Ynysforgan Roundabout	81	861	99.9
Dwr Cymru Welsh Water	River Tawe	YSTRADGYNLAIS WWTW OFF WIND ROAD	48	724	99.8
Dwr Cymru Welsh Water	River Tawe	CSO Ynystawe (Point 86 New Ma)	96	688	97.8
Dwr Cymru Welsh Water	River Tawe	WYCHTREE STREET CSO MORRISTON	79	663	99.9
Dwr Cymru Welsh Water	River Tawe	CSO at Rear of Lonlas Station Road Abercrave	73	426	96.8
Dwr Cymru Welsh Water	River Tawe	CSO 104 NEWBRIDGE ROAD PUMPING STAT	43	414	99.8
Dwr Cymru Welsh Water	River Tawe	Pontardawe Leis Centre CSO Swansea	83	377	98.7
Dwr Cymru Welsh Water	River Tawe	SWN YR AFON CSO, Ystradgynlais	58	348	94.8
Dwr Cymru Welsh Water	River Tawe	CSO 70 A4067 Nthbnd Landore Swansea	92	315	99.9
Dwr Cymru Welsh Water	River Tawe	Rear of Canal Cottage CSO, Abercrave	39	298	96.3
Dwr Cymru Welsh Water	River Tawe	Pentrechwyth Rd CSO	58	291	99.4
Dwr Cymru Welsh Water	River Tawe	CSO at O/S 17 Glantawe Row Ystradgynlais	74	251	99.1
Dwr Cymru Welsh Water	River Tawe	SWO.M'HOLE12 CWMTAWE FM PENRHOS	36	244	97.7
Dwr Cymru Welsh Water	River Tawe	CSO at MH 92 nr Claypon Bridge, Ystradgynlais	35	214	99.4
Dwr Cymru Welsh Water	River Tawe	CSO at Ynysmeudw Warehouse (SOC	41	196	90.1
Dwr Cymru Welsh Water	River Tawe	CSO M'HOLE 14 ABERCRAVE ST.DAVIDS C	58	189	98.1
Dwr Cymru Welsh Water	River Tawe	CSO 12 B4599 Road Bridge	59	166	99.8
Dwr Cymru Welsh Water	River Tawe	Glais CSO	36	117	99.9
Dwr Cymru Welsh Water	River Tawe	Glais SPS	36	117	99.9
Dwr Cymru Welsh Water	River Tawe	CSO at Mason Arms, Ystradgynlais	24	116	99.4
Dwr Cymru Welsh Water	River Tawe	Office Row Car Park Ystalyfera CSO	45	116	99.9
Dwr Cymru Welsh Water	River Tawe	Bonymaen Rd CSO	52	64	98.4
Dwr Cymru Welsh Water	River Tawe	Opp 74 Bonymaen Rd CSO, Swansea ,	49	56	98.6
Dwr Cymru Welsh Water	River Tawe	Pontardawe 2 To R Tawe CSO Swansea	14	53	99.8
Dwr Cymru Welsh Water	River Tawe	Nr Gough Arms MH CSO	14	41	96.7
Dwr Cymru Welsh Water	River Tawe	CSO Godre'r Graig SOC 20. Godre'r	13	19	99.9
Dwr Cymru Welsh Water	River Tawe	Heol Y Nant/Sybil Street Clydach CSO	4	1	79.2
Dwr Cymru Welsh Water	River Tawe	CSO Near Chemical Rd. Morriston	1	0	99.8
Dwr Cymru Welsh Water	River Tawe	CSO at QUARRY ROAD CLYDACH (POINT 125)	0	0	75.9

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

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

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