Merthyr Tydfil and Aberdare was polluted by sewage 3,304 times in 2024
lasting 18,740 hours - that's 2.17 years!
- but monitoring was disabled in some locations, so could be more

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Contains OS Data © Crown copyright & database right 2021-2024
© Top of the Poops 2021-2024
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Totals for Merthyr Tydfil and Aberdare in 2024
73 Sites polluted by Dwr Cymru Welsh Water
3,304 sewage dumps
18,740 h duration
That's 2.17 years! On average 9.1 times a day
Change Over Time
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Constituencies near Merthyr Tydfil and Aberdare
Waterways in Merthyr Tydfil and Aberdare

Pollution Summary 2024

Here are all the reported sewage overflow totals for Merthyr Tydfil and Aberdare in 2024. 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 77 CSO locations had reporting enabled for less than half the year, of which 1 had zero reporting.

Company Waterway Site Sewage Dumps Duration (Hours) Reporting %
Dwr Cymru Welsh Water River Camnant Hirwaun Wastewater Treatment Works 156 2,899 74
Dwr Cymru Welsh Water River Cynon MIKES FIELD CSO ABERAMAN 135 1,847 99.8
Dwr Cymru Welsh Water River Cynon CSO ABERAMAN IND EST ABERAMAN 94 1,076 80.3
Dwr Cymru Welsh Water Taf Fechan PONTSTICILL WWTW 98 1,055 99.8
Dwr Cymru Welsh Water River Cynon CSO Opposite Arthurs Place Trecynon 120 1,014 99.8
Dwr Cymru Welsh Water Taff Bargoed CSO at Bedlinog- Bowling Green 100 820 98.6
Dwr Cymru Welsh Water River Cynon Penderyn CSO - Tank In Field Raked Scre 97 679 97.8
Dwr Cymru Welsh Water River Dare A CSO AT FIELD ADJACENT TO DAVID ST 100 670 97.6
Dwr Cymru Welsh Water Morlais Brook A CSO AT WATERLOO HOUSE MERTHYR 121 659 96.5
Dwr Cymru Welsh Water Taff CSO PONT RHUN MERTHYR TYDFIL 94 609 96.3
Dwr Cymru Welsh Water Pandy Brook TRELEWIS CSO - REAR OF GLYNBARGOED 134 566 96.2
Dwr Cymru Welsh Water River Cynon CSO At Bottom Monk Street 88 477 99.8
Dwr Cymru Welsh Water Nant-Y-Derlwyn ABERDARE FORECOURT CSO LLWYDCOED 76 416 99.8
Dwr Cymru Welsh Water Morlais Brook CSO at The Bont, Merthyr Tydfil 90 412 96.3
Dwr Cymru Welsh Water Taff Fechan PONTSTICILL WWTW 24 385 99.9
Dwr Cymru Welsh Water River Cynon CSO at West Bank Of River South Of A455 Br 89 377 99.8
Dwr Cymru Welsh Water Unnamed Leading To River Cynon Llwydcoed CSO Side of Llwydcoed Motors 70 368 98.9
Dwr Cymru Welsh Water Aberdare Canal Pant-Y-Cerdin CSO, Aberdare 107 359 96.6
Dwr Cymru Welsh Water River Taff A CSO AT JACKSONS BRIDGE 93 347 99.8
Dwr Cymru Welsh Water Nant Morlais Rocky Rd CSO Merthyr Tydfil 78 341 92.9
Dwr Cymru Welsh Water River Cynon CSO AT BOTTOM MONK STREET (Station St Aberdare) 83 273 99.8
Dwr Cymru Welsh Water Pentrebach Brook Dixs Field CSO, Pentrebach, Merthyr 73 263 97.2
Dwr Cymru Welsh Water River Taff CSO COLLEGE CAR PK MERTHYR TYDFIL 53 236 99.8
Dwr Cymru Welsh Water River Cynon Cwmbach CSO - Outside Bro Deg 75 213 97.8
Dwr Cymru Welsh Water River Aman PLEASANT VIEW CSO 71 210 82.5
Dwr Cymru Welsh Water Aman R - Source To Conf River Cynon Aberaman Park Industrial Estate CSO, Aberdare 47 206 99.3
Dwr Cymru Welsh Water River Taff Merthyr Tydfil Georgetown Lines Bridge CSO 36 192 82.7
Dwr Cymru Welsh Water River Taff Gellideg Tai Mawr Rd CSO, Merthyr Tydfil 50 191 99.4
Dwr Cymru Welsh Water Morlais Brook CSO TREVITHICK MONUMENT MERTHYR 76 166 97.2
Dwr Cymru Welsh Water River Taff Quakers Yard CSO, Fiddlers Elbow St, Cynon 30 161 99.1
Dwr Cymru Welsh Water River Taff Quakers Yard CSO, Greenfield Victoria Bridge 34 156 46.6
Dwr Cymru Welsh Water River Cynon Cwmbach Bro Deg Near No44 56 122 98.4
Dwr Cymru Welsh Water Goitre Brook Goitre Lane CSO 21 72 99.5
Dwr Cymru Welsh Water To Nant Gwrangon CSO at Rhigos- Heol Pendarren 40 68 98.9
Dwr Cymru Welsh Water Nant Gwawr CSO at No20 Glancynon Terrace, Aberaman 88 67 41.8
Dwr Cymru Welsh Water River Dare CSO Off Glan Road (St John the Baptist Church) 20 62 63.9
Dwr Cymru Welsh Water River Cynon Aberaman Curre St CSO 35 56 99.5
Dwr Cymru Welsh Water River Cynon River Aberaman Wind St CSO Nr Mardy lodge 47 54 98.7
Dwr Cymru Welsh Water River Cynon HIRWAUN - REAR OF BUTE TERRACE 20 53 99.3
Dwr Cymru Welsh Water River Taff CSO Avenue De Clichy, Merthyr 26 53 99.8
Dwr Cymru Welsh Water River Cynon CSO at Hirwaun Trenant No 66 Rear of Garden 14 51 9.3
Dwr Cymru Welsh Water River Cynon CSO at Cwmbach Side of Police House 36 50 99.6
Dwr Cymru Welsh Water River Cynon Elizabeth St CSO 30 41 79.8
Dwr Cymru Welsh Water River Cynon Canal Rd CSO, Cwmbach 15 37 98.7
Dwr Cymru Welsh Water River Cynon ABERNANT RUGBY CLUB CSO 29 36 99.8
Dwr Cymru Welsh Water River Cynon CSO at Rear of No12 Bonhaul, Cwmbach 15 35 98.9
Dwr Cymru Welsh Water River Cynon CSO at Aberaman 16 34 99.7
Dwr Cymru Welsh Water River Cynon Cwmbach SPS 6 28 99.8
Dwr Cymru Welsh Water Taf Fechan High St CSO, Cefn Coed 32 25 99.1
Dwr Cymru Welsh Water Nant Wenallt And Then To River Cynon Forge Tip CSO Aberdare 23 23 79.7
Dwr Cymru Welsh Water River Cynon Cwmbach Sion Terrace No 11 CSO 17 17 99.1
Dwr Cymru Welsh Water River Aman CSO at Junction of David St & Pant Rd, Aberaman 4 16 85.8
Dwr Cymru Welsh Water River Taff TROEDYRHIW PS 4 11 99
Dwr Cymru Welsh Water River Aman Incline Row CSO, Aberaman 10 8 80.7
Dwr Cymru Welsh Water River Taff Phyllis Street CSO, Troedyrhiw 6 8 99.7
Dwr Cymru Welsh Water Morlais Brook Brewers Arms CSO, Balaclava Rd, Dowlais 16 8 84.1
Dwr Cymru Welsh Water River Cynon Penywaun - Rear Of 37/39 Erw L 13 7 98.1
Dwr Cymru Welsh Water Gadlys Feeder GLADLYS TUDOR TERRACE CSO 21 7 99.3
Dwr Cymru Welsh Water River Cynon Abercwmboi Parkview Capcoch Infant School CSO 11 6 98.9
Dwr Cymru Welsh Water River Cynon No. 29 Maeshyfryd CSO, Cwmbach 7 4 99.4
Dwr Cymru Welsh Water River Cynon CSO at Rear Of St Winifreds Church Hirwa 3 4 99.6
Dwr Cymru Welsh Water River Cynon CSO at Cwmbach Bryngolwg No 45 3 3 99.4
Dwr Cymru Welsh Water Unnamed Leading To Aman River Aberaman Cynon St rear of 6 2 99.6
Dwr Cymru Welsh Water Un Leading To Nant Morlais Dowlais Market St & High St Junction 2 2 97.1
Dwr Cymru Welsh Water River Taff CSO WILLOW GAS WORKS MERTHYR TYDFIL 2 1 94.3
Dwr Cymru Welsh Water River Aman CSO at Aberaman Cardiff Road No 104 5 1 8.9
Dwr Cymru Welsh Water River Cynon No 1 Wellington St CSO, Robertstown 1 1 42.1
Dwr Cymru Welsh Water River Taff 3rd Trunk CSO South of Glan Yr Afon 3 1 20.9
Dwr Cymru Welsh Water River Taff Troedyrhiw, Yew Street CSO 2 0 31.5
Dwr Cymru Welsh Water Nant-Y-Derlwyn Trecynon, Harriet St CSO 3 0 98.7
Dwr Cymru Welsh Water Unnamed Stream And Thence To River Cynon CSO at HIRWAUN - ON TRAMWAY 2 0 82.1
Dwr Cymru Welsh Water Morlais Brook CSO AT DOWLAIS BALACLAVA ROAD 1 0 99.2
Dwr Cymru Welsh Water Aman R - Source To Conf River Cynon Fforchaman Street CSO 1 0 36.3
Dwr Cymru Welsh Water Bargoed Taf CSO at QUAKERS YARD - NEAR PUBLIC HOU 0 0 94
Dwr Cymru Welsh Water River Taff TRUNK CSO 2A OFF ABERFAN ROAD 0 0 99.7
Dwr Cymru Welsh Water River Cynon CSO at Hirwaun Trenant No70 Rear of Garden 0 0 0
Dwr Cymru Welsh Water Morlais Brook Balaclava Rd CSO, Dowlais 0 0 99.7

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. This 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.

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