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Vale of Glamorgan - 2025 Sewage

Polluted by sewage 13,654 hours in 2025 - That's 1.58 years

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Contains OS Data © Crown copyright & database right 2021-2024
© Top of the Poops 2021-2024

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View Annual Sewage Data

You're looking at the totals that we have calculated for sewage in Vale of Glamorgan for 2025. It is an estimate, based on very poor quality live data from the Water Companies. This may not align with the 'official' reported sewage values from the water companies, which is reported in April following then end of the year - so 2025 numbers are reported in April 2026.

What's a potential overflow? If the CSO goes 'Offline' while its Overflowing, we don't know if it stopped overflowing until we get a 'Stop' event.

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Constituencies near Vale of Glamorgan

Daily Data

Jan - 0 hours
Feb - 1,455 hours
Mar - 475 hours
Apr - 451 hours
May - 7 hours
Jun - 199 hours
Jul - 43 hours
Aug - 1 hours
Sept - 717 hours
Oct - 466 hours
Nov - 3,528 hours
Dec - 6,301 hours
Daily data is experimental and data is not guaranteed to be accurate. Please inform us of any issue, we will fix.
Please note: We don't have rainfall data for Wales. If you know where to source it please let us know!
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Totals so far

Company Site Name Receiving Waterway Overflow Days Total Duration (hours) Offline/Potential Pollution
Dwr Cymru Welsh Water Ewenny No.2 Storm Overflow River Ewenni 106 2,130 h 45m -
Dwr Cymru Welsh Water Cowbridge Llanbethian WwTW Storm Overflow River Thaw 108 1,720 h 44m -
Dwr Cymru Welsh Water Llancarfan WwTW Overflow Nant Llancarfan 66 1,180 h 15m -
Dwr Cymru Welsh Water Wick WwTW Overflow River Alyn 107 1,179 h 30m -
Dwr Cymru Welsh Water Coslech WwTW Storm Overflow River Ely 104 1,153 h 30m -
Dwr Cymru Welsh Water Llandow Storm Overflow Llandow Brook 63 1,043 h 11m -
Dwr Cymru Welsh Water Llysworney Storm Overflow Stembridge Brook 42 833 h 17m -
Dwr Cymru Welsh Water Bonvilston East WwTW Overflow Nant Llancarfan 87 832 h 44m -
Dwr Cymru Welsh Water Trerhyngyll Overflow Unnamed tributary of the River Thaw 33 727 h 29m -
Dwr Cymru Welsh Water North Treoes Bridge Storm Overflow Nant Ganna 30 549 h 28m -
Dwr Cymru Welsh Water West Aberthaw WwTW Storm Overflow Bristol Channel 35 489 h -
Dwr Cymru Welsh Water Ystradowen Storm Overflow unnamed tributary of Nant Dyfrygi 20 310 h 51m -
Dwr Cymru Welsh Water Whitebridge Storm Overflow River Ely 22 203 h 15m -
Dwr Cymru Welsh Water B4265 Storm Overflow River Thaw 23 200 h 47m -
Dwr Cymru Welsh Water Barry Docks Pumped Storm Overflow Barry No, 2 Dock 102 127 h 37m -
Dwr Cymru Welsh Water Llantwit Major Beach Road Settled Storm Overflow Coastal Waters - Severn Estuary 11 111 h 4m -
Dwr Cymru Welsh Water Dyfrig Street Storm Overflow Barry Dock No1 17 109 h 57m -
Dwr Cymru Welsh Water Llangan Storm Overflow Canna Brook 30 76 h 45m -
Dwr Cymru Welsh Water Unknown Unknown 18 76 h 39m -
Dwr Cymru Welsh Water Barry Town Long Sea Storm Overflow Severn Estuary 31 72 h -
Dwr Cymru Welsh Water Rock Road Storm Overflow River Thaw 14 61 h 49m -
Dwr Cymru Welsh Water Coldbrook Road Tank Storm Overflow The Cold Brook 8 53 h 45m -
Dwr Cymru Welsh Water Lower Fontygary Overflow Bristol Channel 5 47 h -
Dwr Cymru Welsh Water Peterston-super-Ely WwTW Storm Overflow River Ely 14 44 h 30m -
Dwr Cymru Welsh Water Wenvoe Overflow Wrinstone Brook 11 36 h -
Dwr Cymru Welsh Water Nant Talwg Storm Overflow Nant Talwg 7 33 h 10m -
Dwr Cymru Welsh Water Llantwit Major Beach Road Storm Overflow River Colhuw 4 31 h 30m -
Dwr Cymru Welsh Water Ewenny No.1 Overflow River Ewenni 6 30 h 45m -
Dwr Cymru Welsh Water Daniel Street 1 Storm Overflow Culverted Section of Coldbrook 7 28 h 15m -
Dwr Cymru Welsh Water Weycock Cross Storm Overflow River Weycock 5 23 h 45m -
Dwr Cymru Welsh Water Barry Town Short Sea Storm Overflow Severn Estuary 9 23 h 11m -
Dwr Cymru Welsh Water Whitewell Road 2 Storm Overflow Coldbrook 20 19 h 50m -
Dwr Cymru Welsh Water Robins Lane Storm Overflow Culverted section of Cold brook 8 18 h 41m -
Dwr Cymru Welsh Water Dyfan Road Storm Tank Storm Overflow Culverted section of Coldbrook 8 16 h 25m -
Dwr Cymru Welsh Water Cwm Barry Storm Overflow Barry Brook 9 11 h 42m -
Dwr Cymru Welsh Water Rhoose Storm Overflow Bristol Channel 8 11 h 22m -
Dwr Cymru Welsh Water Craig Penllyne Storm Overflow River Thaw 2 9 h -
Dwr Cymru Welsh Water Atlantic Trading Estate Storm Overflow River Cadoxton 1 3 h 58m -
Dwr Cymru Welsh Water Westward Rise Storm Overflow Nant Talwg 3 3 h 30m -
Dwr Cymru Welsh Water Pontypridd Road Storm Overflow Barry Brook 7 2 h 59m -
Dwr Cymru Welsh Water Coldbrook Road East 2 Storm Overflow Coldbrook 3 2 h 56m -
Dwr Cymru Welsh Water Torbay Terrace Junction Storm Overflow The Rhoose Brook 2 2 h 32m -
Dwr Cymru Welsh Water Harbour Road Barry Town Storm Overflow Barry Harbour 2 2 h 30m -
Dwr Cymru Welsh Water Station Road East Wenvoe Storm Overflow Wrinstone Brook 3 1 h 30m -
Dwr Cymru Welsh Water Broad Street Barry Storm Overflow Unnamed Culvert leading to Barry Dock No, 1 3 1 h -
Dwr Cymru Welsh Water Whitewell Road 1 Storm Overflow Coldbrook 3 0 h 45m -
Dwr Cymru Welsh Water Junction of Claude Road West and Severn Avenue Barry Storm Overflow Barry Brook 2 0 h 45m -
Dwr Cymru Welsh Water Porthkerry Storm Overflow The Whitelands Brook 1 0 h 43m -
Dwr Cymru Welsh Water Price Avenue Storm Overflow Coldbrook 1 0 h 30m -
Dwr Cymru Welsh Water Coldbrook Road East 1 Storm Overflow Culvert leading to Coldbrook 1 0 h 29m -
Dwr Cymru Welsh Water Paget Road Barry Storm Overflow Barry Old Harbour 1 0 h 15m -
Dwr Cymru Welsh Water Colwinston Storm Overflow Tributary of Colwinston Brook 0 0 h -
Dwr Cymru Welsh Water Millfield Drive Storm Overflow River Thaw 0 0 h -
Dwr Cymru Welsh Water Cowbridge Street Barry Storm Overflow Culverted Section of The Coldbrook 0 0 h -
Dwr Cymru Welsh Water Unknown Unknown 0 0 h -
Dwr Cymru Welsh Water Fontygary Fonmon Park Road Storm Overflow Bristol Channel 0 0 h -
Dwr Cymru Welsh Water Nant Talwg Way Storm Overflow Nant Talwg 0 0 h -
Dwr Cymru Welsh Water Cold Knap Storm Overflow Bristol Channel 0 0 h -

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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© 2020-2025 Top-Of-The-Poops CC-BY-SA 4.0,
© Openstreetmap contributors, Contains OS data © Crown copyright and database right 2021-2025,
Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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