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

Pollution Summary 2025

Here are all the reported sewage overflow totals for River Cynon 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 Cynon	MIKES FIELD CSO ABERAMAN	121	1,591	99.9
Dwr Cymru Welsh Water	River Cynon	CSO ABERAMAN IND EST ABERAMAN	112	1,282	99.9
Dwr Cymru Welsh Water	River Cynon	PONTCYNON PIPE BRIDGE CSO ABERCYNON	103	1,165	99.2
Dwr Cymru Welsh Water	River Cynon	Penderyn CSO - Tank In Field Raked Scre	86	573	99
Dwr Cymru Welsh Water	River Cynon	CSO Opposite Arthurs Place Trecynon	96	554	99.8
Dwr Cymru Welsh Water	River Cynon	CSO at West Bank Of River South Of A455 Br	88	449	99.9
Dwr Cymru Welsh Water	River Cynon	CSO At Bottom Monk Street	93	444	99.8
Dwr Cymru Welsh Water	River Cynon	Oxford St CSO, Mountain Ash	85	434	95.5
Dwr Cymru Welsh Water	River Cynon	CSO AT BOTTOM MONK STREET (Station St Aberdare)	84	307	98.7
Dwr Cymru Welsh Water	River Cynon	CSO Opposite Miskin Hotel, far side of railway	68	300	82.2
Dwr Cymru Welsh Water	River Cynon	Cwmbach CSO - Outside Bro Deg	70	214	98.4
Dwr Cymru Welsh Water	River Cynon	Penywaun - Rear Of 37/39 Erw L	52	176	98.8
Dwr Cymru Welsh Water	River Cynon	CSO at Hirwaun Trenant No 66 Rear of Garden	66	152	91
Dwr Cymru Welsh Water	River Cynon	Cwmbach Bro Deg Near No44	52	150	99.1
Dwr Cymru Welsh Water	River Cynon	Glassbrook Terrace CSO, Penrhiwceiber	48	124	99.2
Dwr Cymru Welsh Water	River Cynon	HIRWAUN - REAR OF BUTE TERRACE	40	88	97
Dwr Cymru Welsh Water	River Cynon	ABERNANT RUGBY CLUB CSO	50	85	99.8
Dwr Cymru Welsh Water	River Cynon	NEWTOWN COMMUNITY HALL CSO	32	63	99.7
Dwr Cymru Welsh Water	River Cynon	Cwmbach Sion Terrace No 11 CSO	19	51	99.2
Dwr Cymru Welsh Water	River Cynon	CSO at Cwmbach Side of Police House	24	42	99.5
Dwr Cymru Welsh Water	River Cynon	Aberaman Curre St CSO	32	38	99.8
Dwr Cymru Welsh Water	River Cynon	Elizabeth St CSO	27	33	99.3
Dwr Cymru Welsh Water	River Cynon	Penrhiwceiber Point D CSO	29	30	99.7
Dwr Cymru Welsh Water	River Cynon	Canal Rd CSO, Cwmbach	16	23	98.6
Dwr Cymru Welsh Water	River Cynon	CSO at Rear of No12 Bonhaul, Cwmbach	12	22	99.2
Dwr Cymru Welsh Water	River Cynon	Cwmbach SPS	3	10	99.9
Dwr Cymru Welsh Water	River Cynon	Cwmpennar CSO, Adj Low Rd, Mountain Ash	5	8	94.2
Dwr Cymru Welsh Water	River Cynon	Abercwmboi Parkview Capcoch Infant School CSO	7	3	100
Dwr Cymru Welsh Water	River Cynon	Pentre - Llewellyn Street CSO	6	2	99.6
Dwr Cymru Welsh Water	River Cynon	No 1 Wellington St CSO, Robertstown	7	2	100
Dwr Cymru Welsh Water	River Cynon	CSO at Aberaman	3	1	99.3
Dwr Cymru Welsh Water	River Cynon	TOWN HALL	4	1	99.9
Dwr Cymru Welsh Water	River Cynon	CSO at Cwmbach Bryngolwg No 45	2	0	99.9
Dwr Cymru Welsh Water	River Cynon	No. 29 Maeshyfryd CSO, Cwmbach	2	0	100
Dwr Cymru Welsh Water	River Cynon	CSO at Hirwaun Trenant No70 Rear of Garden	0	0	0
Dwr Cymru Welsh Water	River Cynon	CSO at Rear Of St Winifreds Church Hirwa	0	0	0
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	River Cynon	CSO Meadow Street Pontycymmer	0	0	100

It's a Dirty Business

River Cynon polluted by sewage 1,544 times in 2025 - lasting 8,428 hours

34 Sites polluted by Dwr Cymru Welsh Water

Pollution Summary 2025

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