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Vale of Glamorgan - Live Sewage

Polluted by sewage 7,033 hours in 2026 so far..

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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 so far for 2026. It is an estimate, based on very poor quality live data from the Water Companies. The water companies report their sewage to the Environment Agency every year in April. You can see the last reported year in the other page

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 - 2,214 hours
Feb - 4,818 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 Cowbridge Llanbethian WwTW Storm Overflow River Thaw 53 1,045 h 16m -
Dwr Cymru Welsh Water Ewenny No.2 Storm Overflow River Ewenni 43 919 h 31m -
Dwr Cymru Welsh Water Llandow Storm Overflow Llandow Brook 37 806 h 48m -
Dwr Cymru Welsh Water Wick WwTW Overflow River Alyn 44 780 h 46m -
Dwr Cymru Welsh Water Llysworney Storm Overflow Stembridge Brook 32 751 h 46m -
Dwr Cymru Welsh Water West Aberthaw WwTW Storm Overflow Bristol Channel 33 604 h 45m -
Dwr Cymru Welsh Water Coslech WwTW Storm Overflow River Ely 40 592 h 16m -
Dwr Cymru Welsh Water Bonvilston East WwTW Overflow Nant Llancarfan 34 446 h 16m -
Dwr Cymru Welsh Water Trerhyngyll Overflow Unnamed tributary of the River Thaw 19 380 h 19m -
Dwr Cymru Welsh Water B4265 Storm Overflow River Thaw 23 144 h 27m -
Dwr Cymru Welsh Water Llantwit Major Beach Road Settled Storm Overflow Coastal Waters - Severn Estuary 32 132 h -
Dwr Cymru Welsh Water Barry Town Long Sea Storm Overflow Severn Estuary 19 86 h 45m -
Dwr Cymru Welsh Water Barry Docks Pumped Storm Overflow Barry No, 2 Dock 40 77 h 16m -
Dwr Cymru Welsh Water North Treoes Bridge Storm Overflow Nant Ganna 4 70 h 15m -
Dwr Cymru Welsh Water Whitebridge Storm Overflow River Ely 9 67 h 15m -
Dwr Cymru Welsh Water Ystradowen Storm Overflow unnamed tributary of Nant Dyfrygi 6 51 h -
Dwr Cymru Welsh Water Lower Fontygary Overflow Bristol Channel 2 24 h 30m -
Dwr Cymru Welsh Water Llangan Storm Overflow Canna Brook 7 18 h -
Dwr Cymru Welsh Water Coldbrook Road Tank Storm Overflow The Cold Brook 2 12 h -
Dwr Cymru Welsh Water Cwm Barry Storm Overflow Barry Brook 2 7 h 27m -
Dwr Cymru Welsh Water Rock Road Storm Overflow River Thaw 3 4 h 58m -
Dwr Cymru Welsh Water Nant Talwg Storm Overflow Nant Talwg 1 3 h 29m -
Dwr Cymru Welsh Water Barry Town Short Sea Storm Overflow Severn Estuary 2 2 h 14m -
Dwr Cymru Welsh Water Wenvoe Overflow Wrinstone Brook 2 1 h 45m -
Dwr Cymru Welsh Water Robins Lane Storm Overflow Culverted section of Cold brook 1 1 h 14m -
Dwr Cymru Welsh Water Llantwit Major Beach Road Storm Overflow River Colhuw 1 0 h 30m -
Dwr Cymru Welsh Water Rhoose Storm Overflow Bristol Channel 1 0 h 27m -
Dwr Cymru Welsh Water Peterston-super-Ely WwTW Storm Overflow River Ely 1 0 h 15m -
Dwr Cymru Welsh Water Ewenny No.1 Overflow River Ewenni 0 0 h -
Dwr Cymru Welsh Water Cowbridge Street Barry Storm Overflow Culverted Section of The Coldbrook 0 0 h -
Dwr Cymru Welsh Water Fontygary Fonmon Park Road Storm Overflow Bristol Channel 0 0 h -
Dwr Cymru Welsh Water Dyfan Road Storm Tank Storm Overflow Culverted section of Coldbrook 0 0 h -
Dwr Cymru Welsh Water Craig Penllyne Storm Overflow River Thaw 0 0 h -
Dwr Cymru Welsh Water Station Road East Wenvoe Storm Overflow Wrinstone Brook 0 0 h -
Dwr Cymru Welsh Water Dyfrig Street Storm Overflow Barry Dock No1 0 0 h -
Dwr Cymru Welsh Water Torbay Terrace Junction Storm Overflow The Rhoose Brook 0 0 h -
Dwr Cymru Welsh Water Paget Road Barry Storm Overflow Barry Old Harbour 0 0 h -
Dwr Cymru Welsh Water Harbour Road Barry Town Storm Overflow Barry Harbour 0 0 h -
Dwr Cymru Welsh Water Colwinston Storm Overflow Tributary of Colwinston Brook 0 0 h -
Dwr Cymru Welsh Water Whitewell Road 2 Storm Overflow Coldbrook 0 0 h -
Dwr Cymru Welsh Water Unknown Unknown 0 0 h -
Dwr Cymru Welsh Water Whitewell Road 1 Storm Overflow Coldbrook 0 0 h -
Dwr Cymru Welsh Water Millfield Drive Storm Overflow River Thaw 0 0 h -
Dwr Cymru Welsh Water Llancarfan WwTW Overflow Nant Llancarfan 0 0 h -
Dwr Cymru Welsh Water Unknown Unknown 0 0 h -
Dwr Cymru Welsh Water Broad Street Barry Storm Overflow Unnamed Culvert leading to Barry Dock No, 1 0 0 h -
Dwr Cymru Welsh Water Atlantic Trading Estate Storm Overflow River Cadoxton 0 0 h -
Dwr Cymru Welsh Water Nant Talwg Way Storm Overflow Nant Talwg 0 0 h -
Dwr Cymru Welsh Water Price Avenue Storm Overflow Coldbrook 0 0 h -
Dwr Cymru Welsh Water Coldbrook Road East 2 Storm Overflow Coldbrook 0 0 h -
Dwr Cymru Welsh Water Junction of Claude Road West and Severn Avenue Barry Storm Overflow Barry Brook 0 0 h -
Dwr Cymru Welsh Water Weycock Cross Storm Overflow River Weycock 0 0 h -
Dwr Cymru Welsh Water Cold Knap Storm Overflow Bristol Channel 0 0 h -
Dwr Cymru Welsh Water Westward Rise Storm Overflow Nant Talwg 0 0 h -
Dwr Cymru Welsh Water Coldbrook Road East 1 Storm Overflow Culvert leading to Coldbrook 0 0 h -
Dwr Cymru Welsh Water Pontypridd Road Storm Overflow Barry Brook 0 0 h -
Dwr Cymru Welsh Water Porthkerry Storm Overflow The Whitelands Brook 0 0 h -
Dwr Cymru Welsh Water Daniel Street 1 Storm Overflow Culverted Section of Coldbrook 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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© 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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