Top of the Poops | Constituency Sewage Map | Pontypridd

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Live data for Pontypridd in 2026

So far this year (as of 7 Sept 2026, 07:30) there has been 9,499 hours of sewage overflows, from 67 CSO Combined Sewage Overflow - a device that, when operating, pours combined rainwater & sewage into a waterway s - that's 1.1 years!

Totals for Pontypridd in 2025

46 Sites polluted by Dwr Cymru Welsh Water

2,418 sewage dumps

13,842 hours duration

That's 1.6 years. On average 6.6 times a day

Change Over Time

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Waterways in Pontypridd

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Pollution Summary 2025

Here are all the reported sewage overflow totals for Pontypridd 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 constituency 1 of the total 53 CSO Combined Sewage Overflow - a device that, when operating, pours combined rainwater & sewage into a waterway locations had reporting enabled for less than half the year. Of these 1 had zero reporting.

Company	Waterway	Site	Sewage Dumps	Duration (Hours)	Reporting %
Dwr Cymru Welsh Water	River Taff	CILFYNYDD STW CILFYNYDD PONTYPRID	112	1,698	97.7
Dwr Cymru Welsh Water	River Cynon	PONTCYNON PIPE BRIDGE CSO ABERCYNON	103	1,165	99.2
Dwr Cymru Welsh Water	River Ely	DUFFRYN ISAF SEWAGE TREATMENT WORKS	61	903	99.8
Dwr Cymru Welsh Water	River Taff	Tonteg Road, Upper Boat CSO and Pumping Station Emergency Overflow	119	851	99.9
Dwr Cymru Welsh Water	Nant Myddlyn	CSO ADJACENT TO PARISH ROAD BEDDA	129	815	98.6
Dwr Cymru Welsh Water	River Taff	CYNON VALLEY STW GLYNCOCH PONTY	64	778	99.9
Dwr Cymru Welsh Water	River Taff	Abercynon Wood Rd SPS	66	703	99.9
Dwr Cymru Welsh Water	River Rhondda	A COMBINED SEWER OVERFLOW GYFEILLON	132	657	99.9
Dwr Cymru Welsh Water	Ewenny Fach	CSO at Hillside Avenue Llanharan	115	614	98.3
Dwr Cymru Welsh Water	Nant Clydach	Tank Near Pit CSO Ynysybwl	90	553	89.7
Dwr Cymru Welsh Water	Nant Clydach	GLYN STREET CSO GLYN ST YNYSYBWL	98	521	99.3
Dwr Cymru Welsh Water	River Cynon	Oxford St CSO, Mountain Ash	85	434	95.5
Dwr Cymru Welsh Water	River Rhondda	CSO at Pwllgwuan Syphons, Millfield, Pontypridd	92	419	98.8
Dwr Cymru Welsh Water	River Taff	Crossbrook St CSO, Pontypridd	62	379	98.8
Dwr Cymru Welsh Water	River Taff	Cilfynydd STW Cilfynydd Pontypridd Settled Storm	20	329	99.8
Dwr Cymru Welsh Water	Culvert	NEW ROAD SEWERAGE SYSTEM (REDESIGNE	29	327	96.3
Dwr Cymru Welsh Water	River Ely	Lanelay Park - CSO	83	312	99.9
Dwr Cymru Welsh Water	River Cynon	CSO Opposite Miskin Hotel, far side of railway	68	300	82.2
Dwr Cymru Welsh Water	Ewenni Fach	CSO SOUTH OF RAILWAY LLANHAREN	74	290	99.9
Dwr Cymru Welsh Water	Nant Clydach	Old Parish Road CSO, Ynysbwl	83	253	98.3
Dwr Cymru Welsh Water	Nant Clydach	CSO at Clydach Rd, Ynysbwl	47	228	99.3
Dwr Cymru Welsh Water	River Taff	YNYSANGHARAD PARK CSO	93	217	99.9
Dwr Cymru Welsh Water	River Clun	Penygawsi CSO	35	173	99.1
Dwr Cymru Welsh Water	River Taff	Rhydfelin CSO Off Lionel Terrace	32	154	99.9
Dwr Cymru Welsh Water	River Cynon	Glassbrook Terrace CSO, Penrhiwceiber	48	124	99.2
Dwr Cymru Welsh Water	Nant Arian	New Society Garage CSO	43	90	99.9
Dwr Cymru Welsh Water	Nant Clydach	CSO O/S 2 Clydach Terrace, Ynysybwl	34	88	80.2
Dwr Cymru Welsh Water	River Taff	CASTLE INN CSO ASSET NO 32280	30	86	63.6
Dwr Cymru Welsh Water	River Cynon	NEWTOWN COMMUNITY HALL CSO	32	63	99.7
Dwr Cymru Welsh Water	River Taff	Pontypridd West Street CSO	63	52	99.2
Dwr Cymru Welsh Water	Rhondda River	Pavia Courth CSO, Pontypridd	44	47	99
Dwr Cymru Welsh Water	Nant Tyrarlwudd	Penycoedcae SPS	64	46	99.9
Dwr Cymru Welsh Water	R Cynon - Conf Aman R To Conf R Taff	Station Terrace CSO, Penrhiwceiber	30	38	80.1
Dwr Cymru Welsh Water	River Cynon	Penrhiwceiber Point D CSO	29	30	99.7
Dwr Cymru Welsh Water	River Rhondda	Lower Mill Street CSO Pontypridd	14	28	88
Dwr Cymru Welsh Water	River Rhondda	Pellgwaun CSO	23	23	98.2
Dwr Cymru Welsh Water	River Clun Via An Unnamed Ditch	Talbot Green CSO	27	14	76.3
Dwr Cymru Welsh Water	River Cynon	Cwmpennar CSO, Adj Low Rd, Mountain Ash	5	8	94.2
Dwr Cymru Welsh Water	Nant Cae-Dudwg	End of Park Place CSO, Cilfynydd	9	8	99.7
Dwr Cymru Welsh Water	Nant Cymdda Bach	Brynteg Park Pumping Station Beddau	5	5	99.9
Dwr Cymru Welsh Water	River Rhondda	Lanelay Crescent CSO, Maesycoed	9	3	99.8
Dwr Cymru Welsh Water	R Taff - Conf Rhondda R To Castle Street	CSO at Treforest Llantwit Rd A	6	2	99.8
Dwr Cymru Welsh Water	River Rhondda	Pwllgwaun Rd CSO, pontypridd	5	1	99.9
Dwr Cymru Welsh Water	River Cynon	TOWN HALL	4	1	99.9
Dwr Cymru Welsh Water	Taff	Cardiff Road CSO, Pontypridd	1	0	100
Dwr Cymru Welsh Water	River Nant Felin Fach	Llanharry SPS	1	0	99.9
Dwr Cymru Welsh Water	River Cynon	Abercynon Rugby Club CSO	0	0	99.3
Dwr Cymru Welsh Water	River Cynon	Duffryn Rd Mount 2 CSO	0	0	0
Dwr Cymru Welsh Water	River Cynon	No 10 Hamilton St CSO, Mountain Ash	0	0	100
Dwr Cymru Welsh Water	Nant Cae-Dudwg	PARK PLACE CSO	0	0	99.9
Dwr Cymru Welsh Water	River Taff	Sion Street Sewage Pumping Station	0	0	99.9
Dwr Cymru Welsh Water	River Taff	Taff St CSO, Pontypridd	0	0	99.9
Dwr Cymru Welsh Water	River Taff	YNYSANGHARAD HIGH LEVEL RELIEF CSO	0	0	97.6

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

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