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Blaenau Gwent Caerffili Rhymni

Polluted by sewage 4,311 times in 2025 lasting 20,476 hours - That's 2.37 years!

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 Blaenau Gwent Caerffili Rhymni in 2025

116 Sites polluted by Dwr Cymru Welsh Water
4,311 sewage dumps
20,476 hours duration
That's 2.37 years. On average 11.8 times a day

Change Over Time

Senedd Constituencies near Blaenau Gwent Caerffili Rhymni

Westminster Constituencies within Blaenau Gwent Caerffili Rhymni

To see live data by overflow, go to the Westminster Constituency, then 'live data'

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Pollution Summary 2025

Here are all the reported sewage overflow totals for Blaenau Gwent Caerffili Rhymni 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 4 of the total 135 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 4 had zero reporting.

Company Waterway Site Sewage Dumps Duration (Hours) Reporting %
Dwr Cymru Welsh Water River Clydach BRYNMAWR STW BLACKROCK BRYNMAWR 122 1,583 99.9
Dwr Cymru Welsh Water River Rhymney CSO at Glan-yr-Afon Nursing Home No2, Pengam 110 1,203 98.9
Dwr Cymru Welsh Water Porset Brook CSO at Lansbury Park Estate 113 1,181 98.5
Dwr Cymru Welsh Water Sirhowy River CSO 20 OLD MILL NEWPORT ROAD 111 1,022 99.9
Dwr Cymru Welsh Water River Rhymney CWM LAS CSO 82 864 98.6
Dwr Cymru Welsh Water River Rhymney Abertysswg Rugby Playing Field CSO 92 793 99
Dwr Cymru Welsh Water Nant Bargoed Deri, Darran Valley CSO 68 764 99.9
Dwr Cymru Welsh Water River Ebbw RIVERSIDE DOCTORS SURGERY EBBW VALE CSO 102 758 99.9
Dwr Cymru Welsh Water River Sirhowy Tredegar Park Place CSO 161 709 94.9
Dwr Cymru Welsh Water River Bargoed Bedwellty Road CSO 155 667 97.7
Dwr Cymru Welsh Water River Rhymney Tredomen AFC CSO, Ystrad Mynach 72 582 99.9
Dwr Cymru Welsh Water River Rhymney A CSO AT PONTLOTTYN 89 572 99.9
Dwr Cymru Welsh Water River Sirhowy Springfield Est CSO, Pontllanfraith 83 489 97.1
Dwr Cymru Welsh Water River Rhymney CSO At New Tredegar Adj Rhosyn Gwyn 38 440 99.9
Dwr Cymru Welsh Water Nant Y Aber Combined Sewer Overflow at Bryn Siriol 59 376 99.8
Dwr Cymru Welsh Water River Ebbw The Square Street, Abertillery CSO 52 344 96
Dwr Cymru Welsh Water Nant Yr Aber Crossways Retail Park CSO 40 316 95.1
Dwr Cymru Welsh Water River Sirhowy CSO 32075 Opposite Garibaldi Bridge 75 302 99.1
Dwr Cymru Welsh Water River Ebbw Fawr CWM SSO 49 299 99.6
Dwr Cymru Welsh Water River Rhymney CSO at Glan-yr-Afon Nursing Home 1 69 253 100
Dwr Cymru Welsh Water Ebbw Fach River Abertillery Six Bells Colliery No. 2 CSO 34 252 97
Dwr Cymru Welsh Water River Sirhowy A CSO AT REAR OF CHURCH SQ TREDEGAR 79 250 99.8
Dwr Cymru Welsh Water Nant Cylla Oaks End Close CSO 75 245 99.3
Dwr Cymru Welsh Water River Rhymney CSO NEAR RHYMNEY STATION 58 244 99.2
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, South of Pochin Crescent 39 233 91.1
Dwr Cymru Welsh Water River Sirhowy CSO OPP 1 DUKESTOWN ROAD TREDEGAR 60 228 99.9
Dwr Cymru Welsh Water River Rhymney BEDWAS SUNNYBANK FARM CSO 45 225 98.9
Dwr Cymru Welsh Water River Rymney MAESYCWMMER A472 JUNCTION CSO 66 223 99.6
Dwr Cymru Welsh Water River Ebbw Fach Berea Close CSO, Blaina 46 211 97.5
Dwr Cymru Welsh Water River Rhymney CSO at Pengham High St near Bridge 49 206 100
Dwr Cymru Welsh Water Ebbw Fawr CSO at Ebbw Vale Victoria Reclamation Scheme 26 201 99.6
Dwr Cymru Welsh Water River Sirhowy CSO Opposite White Lion Cottages 55 199 99.3
Dwr Cymru Welsh Water River Rhymney Tir-y-Berth behind William St 63 192 99.2
Dwr Cymru Welsh Water Nant Yr Ystruth CSO at LIBRARY ON HIGH STREET BLAINA 60 190 97.9
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, Edward Terrace Nr River Bridge 69 190 99
Dwr Cymru Welsh Water River Rhymney CSO AT REAR OF MEMORIAL HOSPITAL 58 188 99
Dwr Cymru Welsh Water Sirhowy River CSO at Tredegar, Vicarage Road Rear of Hill Rest 56 178 99.3
Dwr Cymru Welsh Water River Rhymney A CSO AT YSTRAD MYNACH BRIDGE 57 178 98.1
Dwr Cymru Welsh Water Nant Bargoed Rhymney CSO AT ABERBARGOED VIADUCT 18 168 99.9
Dwr Cymru Welsh Water River Rhymney Rhymney Carno St Bute House CSO 48 144 99.2
Dwr Cymru Welsh Water Sirhowy River CSO 19 Gryphonn Concrete Products 85 139 99.9
Dwr Cymru Welsh Water River Rhymney TRELYN LANE CSO FLEUR-DE-LIS 37 130 99.8
Dwr Cymru Welsh Water Rhymney R - Source To Conf Nant Bargod Rhymni Pontlottyn Newydd Farm CSO 43 128 99.7
Dwr Cymru Welsh Water Ebbw River CSO 29 OPP THE CROFT STEELWORKS RD 45 122 66.6
Dwr Cymru Welsh Water River Sirhowy Old Tram Rd CSO, Pontllanfraith 36 112 97.2
Dwr Cymru Welsh Water Rhymney R - Source To Conf Nant Bargod Rhymni Pontlottyn Recreation Ground CSO 46 110 99.3
Dwr Cymru Welsh Water Ebbw Fawr GOSPEL HALL CSO BEAUFOR RD EBBW VA 49 106 99.9
Dwr Cymru Welsh Water River Rhymney CSO BARGOED 55 101 99.9
Dwr Cymru Welsh Water Sirhowy River WVTS - Wattsville (Recreation Ground) CSO 40 100 94.6
Dwr Cymru Welsh Water River Rhymney CSO Nr Bethania Cottages 54 99 69.5
Dwr Cymru Welsh Water Sirhowy River CSO 32084 Scwrfa Road, Tredegar 43 96 99.9
Dwr Cymru Welsh Water River Clydach Opp Bridge End Inn CSO 44 94 99
Dwr Cymru Welsh Water River Tillery Glan Ebbw terrace CSO, Abertillery 37 88 99.1
Dwr Cymru Welsh Water River Ebbw Ebbw Vale PontyGof 38 84 93.6
Dwr Cymru Welsh Water Ebbw Fach R - Source To Conf Ebbw R CSO AT ABERTILLERY FOUNDARY BRIDGE NR CAR PARK 34 80 99.3
Dwr Cymru Welsh Water Ebbw Fawr CSO 31 ADJ STEELWORKS RD CAR PARK 21 79 99.9
Dwr Cymru Welsh Water Ebbw Fach Abertillery Six Bells Colliery No.1 CSO 10 72 99.6
Dwr Cymru Welsh Water Ebbw River Allotment Rd CSO 13 72 99.9
Dwr Cymru Welsh Water River Rhymney Forge Engineering CSO, Bedwas 24 67 97.4
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, Railway View, opposite No13 52 64 99.5
Dwr Cymru Welsh Water Ebbw River Tredegar Rd Nr 62A, Ebbw Vale 29 64 99.7
Dwr Cymru Welsh Water River Rhymney CSO Opposite Bowen Ind Estate, Aberbargoed 36 60 99.7
Dwr Cymru Welsh Water Sirhowy River WVTS-WYLLIE HALT SSO 33 53 98
Dwr Cymru Welsh Water Ebbw Fach South Griffin Colliery CSO 17 52 99.5
Dwr Cymru Welsh Water River Sirhowy WVTS-Tredegar (MH G57) CSO 21 46 100
Dwr Cymru Welsh Water River Rhymney CSO at rear of Margaret St., Gilfach 24 44 96.9
Dwr Cymru Welsh Water Sirhowy River Tredegar Vale Terrace R/O 61 40 42 99.7
Dwr Cymru Welsh Water Sirhowy River Morgan St CSO, Tredegar 38 42 99.6
Dwr Cymru Welsh Water River Rhymney CSO ASSET NO 90411 PENGAM 40 36 96.9
Dwr Cymru Welsh Water Nant Melyn/Rasa Brook Coedcae House CSO 18 32 99.2
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, Vale Terrace R/O 101 U/S Garage 31 29 92.1
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, Brompton SSO 1 MH No GN86A 10 27 99.7
Dwr Cymru Welsh Water Ebbw Fach Abertillery Park View Terrace CSO 14 27 99.9
Dwr Cymru Welsh Water River Rhymney Asset No. 32207 Celtic Steel Factory CSO 17 27 99.6
Dwr Cymru Welsh Water River Sirhowy Bottom of Nine Mile Point Colliery CSO 9 26 98.5
Dwr Cymru Welsh Water Ebbw Fawr CSO Adj to The Institute 13 25 99.9
Dwr Cymru Welsh Water Ebbw River CWM (EBBW VALE) CSO 25 22 99.4
Dwr Cymru Welsh Water River Rhymney High St CSO, Glan-y-Nant 12 18 99.8
Dwr Cymru Welsh Water River Ebbw Fach West Side Sewer CSO 15 15 99.4
Dwr Cymru Welsh Water Ebbw Fach CSO at Abertillery Six Bells 22 14 99.3
Dwr Cymru Welsh Water Ebbw Fawr CSO at Opp No 11 Brynhyfryd Terr Ebbw Vale 20 14 99.9
Dwr Cymru Welsh Water Nant Yr Aber Graig-Y-Fedw CSO 19 10 95.5
Dwr Cymru Welsh Water Nant Cwm-Parc 64 Commercial Streetreet CSO, Senghenydd 17 10 95.4
Dwr Cymru Welsh Water Sirhowy River Tredegar Ladies Row CSO o/s School Entrance 10 9 99.6
Dwr Cymru Welsh Water Ebbw River Excelsior Street (rear lane) 8 8 93.2
Dwr Cymru Welsh Water River Ebbw Cwn Marine St CSO 7 7 99.8
Dwr Cymru Welsh Water River Ebbw Fach WVTS-Nantyglo Station SSO 8 7 99.9
Dwr Cymru Welsh Water River Rhymney Newport Rd CSO, Trethomas 6 7 99.4
Dwr Cymru Welsh Water River Ebbw Fach CSO at Limestone Road 5 7 100
Dwr Cymru Welsh Water River Rhymney Forge Rd CSO, Machen 8 6 90.3
Dwr Cymru Welsh Water Culverted River Fac CSO at Nantyglo Market Rd under crash barrier 8 6 99.8
Dwr Cymru Welsh Water River Rhymney A CSO AT BIRTHDIR NEAR STATION 3 5 99.9
Dwr Cymru Welsh Water Nant Yr Aber CSO Rear Commerc'l St Senghenydd 8 5 99.9
Dwr Cymru Welsh Water Ebbw River Brooklyn Terrace CSO 16 4 99.7
Dwr Cymru Welsh Water Nant Yr Aber Windsor Place Senghenydd CSO 6 4 94.1
Dwr Cymru Welsh Water Ebbw River CSO AT LLANHILLETH DISUSED COLLIERY 15 4 99.7
Dwr Cymru Welsh Water Rhymney Bargoed Colliery CSO 10 4 99.9
Dwr Cymru Welsh Water Ebbw Fawr Beaufort Terrace CSO 7 3 96.1
Dwr Cymru Welsh Water Rhymney R - Nant Bargod Rhymni To Conf Nant Cyl Fleur-de-Lys - Rear of Glanddu CSO 6 3 99.6
Dwr Cymru Welsh Water River Bargoed 63 Bedwellty Rd CSO 10 2 100
Dwr Cymru Welsh Water River Sirhowy Islwyn Rd CSO, Crosskeys 7 2 96.9
Dwr Cymru Welsh Water River Rhymney CSO at Trelyn Park 4 1 99.9
Dwr Cymru Welsh Water Ebbw Fawr CSO at Ebbw Vale Junction of Tredegar Rd & Harcourt St 5 1 99.8
Dwr Cymru Welsh Water Ebbw River Commercial Rd 4 1 99.9
Dwr Cymru Welsh Water Rhymney River Old Prince Albert Hotel CSO, Hengoed 3 1 100
Dwr Cymru Welsh Water Rasa Brook Under Flyover 3 0 99.1
Dwr Cymru Welsh Water Ebbw Fach River Abertillery Victoria Road Six Bells CSO 2 0 93.6
Dwr Cymru Welsh Water River Sirhowy CSO at Tredegar, Vale Terrace R/O 123 2 0 100
Dwr Cymru Welsh Water Ebbw Fach OLD SOUTH GRIFFIN COLLIERY CSO 2 0 99.9
Dwr Cymru Welsh Water Nant-Yr-Aber 86 Nantgarw Rd CSO 2 0 98.1
Dwr Cymru Welsh Water River Sirhowy Railway Cottages CSO, Cwmfelinfach 2 0 100
Dwr Cymru Welsh Water River Ebbw Fach Abertillery Six Bells Rd 1 0 100
Dwr Cymru Welsh Water River Tillery CSO at R/O ST MICHAELS CHURCH ABERTILLERY 1 0 99.9
Dwr Cymru Welsh Water River Tillery Commercial St CSO, Abertillery 1 0 100
Dwr Cymru Welsh Water Rhymney River New Tredegar Birch Grove 1 0 99.3
Dwr Cymru Welsh Water Nant Yr Aber Abertridwr Coed Cae Road 1 CSO 1 0 84.7
Dwr Cymru Welsh Water River Rhymney Aberbargoed CSO 0 0 96.3
Dwr Cymru Welsh Water Sirhowy River CSO AT REAR OF NO1 ALEXANDRA PLACE 0 0 0
Dwr Cymru Welsh Water River Ebbw CSO NO.32031 EBBW VALE RUGBY GROUND 0 0 98.4
Dwr Cymru Welsh Water Ebbw Fawr CSO O/S Beaufort Arms, Beaufort Rd, Ebbw Vale 0 0 0
Dwr Cymru Welsh Water Ebbw Fawr CSO at Ebbw Vale Beaufort Rd & Badminton Grove Junction 0 0 0
Dwr Cymru Welsh Water Ebbw Fawr Via A Surface Water Culvert CSO at Ebbw Vale Queens Square 0 0 100
Dwr Cymru Welsh Water River Ebbw CSO at R/O PH Beaufort Rd / R/O 23 Lillian Grove 0 0 100
Dwr Cymru Welsh Water Ebbw River CSO at Rear of 4 Harcourt Street, Ebbw Vale 0 0 99.7
Dwr Cymru Welsh Water River Sirhowy CSO at St James Close Maes-Y-Coed,Tredegar 0 0 100
Dwr Cymru Welsh Water Ebbw Fach Castle St CSO, Abertillery 0 0 99.7
Dwr Cymru Welsh Water Ebbw River Lambs Square CSO 0 0 100
Dwr Cymru Welsh Water River Ebbw Lambs Square/Lower Square 0 0 97.6
Dwr Cymru Welsh Water Ebbw Fach Nantyglo Farm Rd/Market Rd Junction CSO 0 0 100
Dwr Cymru Welsh Water River Tillery Tillery St No9 CSO, Abertillery 0 0 100
Dwr Cymru Welsh Water Unnamed Drain To Ebbw Fach WVTS-Cwmtillery CSO 0 0 0
Dwr Cymru Welsh Water River Rhymney COMBINED SEWER OVERFLOW SERVING 0 0 99.9
Dwr Cymru Welsh Water Nant Caeach Combined Sewer Overflow at Rear of 33 Church Street 0 0 100
Dwr Cymru Welsh Water River Rhymney OLD PRINCE ALBERT HOTEL HENGOED 0 0 100
Dwr Cymru Welsh Water River Rhymney Rear of Williams St CSO 0 0 100

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.

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Analysing sewage pollution by the Water Industry

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