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Bangor Aberconwy - 2025 Sewage

Polluted by sewage 33,594 hours in 2025 - That's 3.89 years

© OpenStreetMap contributors
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 Bangor Aberconwy 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 Bangor Aberconwy

Daily Data

Jan - 0 hours
Feb - 1,467 hours
Mar - 538 hours
Apr - 383 hours
May - 561 hours
Jun - 1,932 hours
Jul - 1,148 hours
Aug - 620 hours
Sept - 4,745 hours
Oct - 2,346 hours
Nov - 10,084 hours
Dec - 9,761 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 Cwm Penmachno WwTW Storm Overflow River Machno 230 5,176h 9m -
Dwr Cymru Welsh Water Dolwyddelan WwTW Storm Overflow Afon Lledr 169 3,008h 15m -
Dwr Cymru Welsh Water Capel Curig WwTW Storm Overflow Afon Lliw 193 2,302h 18m -
Dwr Cymru Welsh Water Cwm Penmachno Storm Overflow unnamed ditch 110 1,742h 49m -
Dwr Cymru Welsh Water Talybont WwTW Storm Overflow River Dulyn 96 1,630h 17m -
Dwr Cymru Welsh Water Tregarth WwTW Storm Overflow Afon Ogwen 96 1,613h 48m -
Dwr Cymru Welsh Water Trefriw WwTW Storm Overflow River Crafnant 101 1,573h 27m -
Dwr Cymru Welsh Water Bethesda WwTW Storm Overflow River Ogwen 115 1,275h 53m -
Dwr Cymru Welsh Water Llangernyw WwTW Overflow Elwy 71 1,102h 39m -
Dwr Cymru Welsh Water Betws Yn Rhos WwTW Storm Overflow Tributary of Afon Dulas 63 1,086h 23m -
Dwr Cymru Welsh Water Penmaenmawr WwTW Storm Overflow Coastal Waters - Conwy Bay 64 1,047h 19m -
Dwr Cymru Welsh Water Bangor Treborth WwTW Storm Overflow Menai Strait 69 966h 21m -
Dwr Cymru Welsh Water Llanrwst WwTW Settled Storm Overflow River Conwy 67 934h 17m -
Dwr Cymru Welsh Water Mill Road Betws-Y-Coed Storm Overflow Afon Lliw 48 842h 48m -
Dwr Cymru Welsh Water Betws-Y-Coed Storm Overflow River Conwy 71 823h 11m -
Dwr Cymru Welsh Water Tregarth Bron Ogwen Storm Overflow Afon Ogwen 41 679h 25m -
Dwr Cymru Welsh Water Llan Penmachno WwTW Storm Overflow River Machno 58 596h 41m -
Dwr Cymru Welsh Water Rock Terrace Storm Overflow River Ogwen 63 531h 40m -
Dwr Cymru Welsh Water Aber Storm Overflow Menai Strait 31 479h 11m -
Dwr Cymru Welsh Water Pwll-Glas WwTW Storm Overflow River Clwyd 40 460h 44m -
Dwr Cymru Welsh Water Eglwysbach WwTW Storm Overflow River Hiraethlyn 25 383h 5m -
Dwr Cymru Welsh Water Rowen WwTW Storm Overflow Afon Roe 77 381h 20m -
Dwr Cymru Welsh Water Llanrwst WwTW Storm Overflow River Conwy 72 375h 21m -
Dwr Cymru Welsh Water Betws-Y-Coed Pentre Ddu Storm Overflow Afon Lliw 38 357h 14m -
Dwr Cymru Welsh Water Trefriw Main Storm Overflow River Conwy 48 355h 26m -
Dwr Cymru Welsh Water Betws-Y-Coed WwTW Storm Overflow Afon Lliw 70 271h 52m -
Dwr Cymru Welsh Water Glasinfryn Storm Overflow Afon Cegin 39 266h 9m -
Dwr Cymru Welsh Water Pendraw R Llan Glan Conwy Storm Overflow River Conwy 17 239h 24m -
Dwr Cymru Welsh Water B5382 Llangernyw Storm Overflow River Elwy 42 229h 15m -
Dwr Cymru Welsh Water Dolwyddelan Storm Overflow Afon Lledr 31 189h 28m -
Dwr Cymru Welsh Water Cerrigydrudion WwTW Storm Overflow Afon Nug 46 182h 41m -
Dwr Cymru Welsh Water Tyn-y-Groes WwTW Storm Overflow River Conwy 31 176h 24m -
Dwr Cymru Welsh Water Llanfairfechan Park Crescent Storm Overflow Afon Llanfairfechan 71 175h 45m -
Dwr Cymru Welsh Water Marine Crescent Deganwy Storm Overflow Estuarial Waters of the River Conwy 56 167h -
Dwr Cymru Welsh Water Gwydyr Road Dolgarrog Storm Overflow River Conwy 26 163h 15m -
Dwr Cymru Welsh Water Clawddnewydd WwTW Storm Overflow Tributary of the Nant-Y-Cefn 18 155h 45m -
Dwr Cymru Welsh Water Maes Bleddyn Storm Overflow Tributary of Afon Ogwen 34 140h 11m -
Dwr Cymru Welsh Water Penrhyn-Isaf Road Penrhyn Bay Storm Overflow Penrhyn Bay 58 130h 42m -
Dwr Cymru Welsh Water Waterloo Bridge Storm Overflow River Conwy 19 116h 49m -
Dwr Cymru Welsh Water Llanllechid Overflow Afon-y-Llan 11 114h 32m -
Dwr Cymru Welsh Water Morfa Road Penrhyn Bay Storm Overflow Coastal Waters - Penrhyn Bay 17 104h 20m -
Dwr Cymru Welsh Water Pwll-Glas WwTW Inlet Storm Overflow River Clwyd 16 90h 30m -
Dwr Cymru Welsh Water Nebo Road Llanrwst Storm Overflow Afon Nant-y-Goron 47 69h 53m -
Dwr Cymru Welsh Water Tan Y Ffordd Dolgarrog Storm Overflow River Conwy 22 66h 56m -
Dwr Cymru Welsh Water Rhostrehwfa Storm Overflow River Cledwen 14 65h 19m -
Dwr Cymru Welsh Water Llandudno West Shore Storm Overflow Conwy Bay 13 63h 45m -
Dwr Cymru Welsh Water Llanrwst Storm Overflow River Conwy 5 62h 50m -
Dwr Cymru Welsh Water Pentrefoelas WwTW Storm Overflow Afon Merddwr 10 60h 28m -
Dwr Cymru Welsh Water Llanfair Talhaiarn WwTW Storm Overflow River Elwy 16 57h 45m -
Dwr Cymru Welsh Water Dale Road Storm Overflow Conwy Bay 52 57h 6m -
Dwr Cymru Welsh Water Glanwydden Storm Overflow Afon Wydden 12 54h 57m -
Dwr Cymru Welsh Water Tan-y-Fedw Trefriw Storm Overflow Afon Crafnant 15 49h 21m -
Dwr Cymru Welsh Water Llanfairfechan No 1 Storm Overflow Afon Llanfairfechan 33 48h 10m -
Dwr Cymru Welsh Water Marl Drive Llandudno Storm Overflow Afon Wydden 6 31h -
Dwr Cymru Welsh Water TalyBont WwTW Storm Overflow Afon Ogwen 13 26h 43m -
Dwr Cymru Welsh Water Betws-Y-Coed Muriau Storm Overflow River Conwy 21 25h 22m -
Dwr Cymru Welsh Water Conwy Gyffin Storm Overflow River Conwy 17 23h 32m -
Dwr Cymru Welsh Water Llandudno Junction Glan-Y-Mor Road Storm Overflow Estuarial Waters of the River Conwy 10 23h 14m -
Dwr Cymru Welsh Water Beach Road Bangor Storm Overflow Menai Strait 8 20h -
Dwr Cymru Welsh Water Lower Gate Street Conwy Storm Overflow River Conwy Estuary 8 19h 57m -
Dwr Cymru Welsh Water Treborth Bangor WwTW Overflow Menai Strait 8 14h 55m -
Dwr Cymru Welsh Water Bangor Beach Road Overflow Menai Strait 6 14h -
Dwr Cymru Welsh Water Morfa Drive Conwy Storm Overflow River Conwy 10 13h 47m -
Dwr Cymru Welsh Water Penaenmawr Station Storm Overflow Coastal waters via a culvert 7 12h 47m -
Dwr Cymru Welsh Water Conwy Harbour Overflow River Conwy 8 10h 26m -
Dwr Cymru Welsh Water Penmaenmawr Promenade Storm Overflow Coastal Waters - Penmaenmawr 4 9h 10m -
Dwr Cymru Welsh Water Penmaenmawr WwTW Overflow Conwy Bay 4 8h 7m -
Dwr Cymru Welsh Water Llandudno Road Penrhyn Bay Storm Overflow Afon Ganol 8 7h 44m -
Dwr Cymru Welsh Water Glan Y Mor Road Deganwy Tywyn Storm Overflow River Conwy 8 7h 33m -
Dwr Cymru Welsh Water Hill View Road Llanrhos Storm Overflow Unnamed Ditch 6 7h 10m -
Dwr Cymru Welsh Water Penrhyn Hill Storm Overflow Coastal Waters - Penrhyn Bay 10 6h -
Dwr Cymru Welsh Water Coleg Normal Overflow Menai Strait 4 3h 30m -
Dwr Cymru Welsh Water Llandudno Conway Road Storm Overflow Afon Wydden 2 3h 19m -
Dwr Cymru Welsh Water Pentre Llanrhaeadr Storm Overflow Nant Mawr 1 2h 45m -
Dwr Cymru Welsh Water Llansannan Storm Overflow River Aled 3 2h 41m -
Dwr Cymru Welsh Water Deganwy Deganwy Road Storm Overflow Conwy Estuary 3 2h 9m -
Dwr Cymru Welsh Water Biwla Storm Overflow Nant Garreg Ddu 3 1h 14m -
Dwr Cymru Welsh Water Pentre Felin Betws Y Coed Overflow Afon Lliw 2 0h 28m -
Dwr Cymru Welsh Water Llandudno Road Penrhyn Bay Overflow Afon Ganol East 0 0h -
Dwr Cymru Welsh Water Meirion Road Storm Overflow Estuarial Waters 0 0h -
Dwr Cymru Welsh Water Gorad Road Bangor Storm Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Ganol Disinfected Overflow Afon Ganol 0 0h -
Dwr Cymru Welsh Water Glan Traeth Bangor Overflow Afon Cegin 0 0h -
Dwr Cymru Welsh Water King Georges Field Overflow Culvert to Bangor Mud Flats 0 0h -
Dwr Cymru Welsh Water Hendre Road Conwy Storm Overflow Afon Gyffin 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Betws-Yn-Rhos Recreation Ground Storm Overflow River Dulas 0 0h -
Dwr Cymru Welsh Water Tremarl Llandudno Junction Overfow Unname Watercourse 0 0h -
Dwr Cymru Welsh Water Near Penmaenmawr Dwygyfylchi Storm Overflow Afon Gyrach 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Mill Hill Storm Overflow Afon Gyffin 0 0h -
Dwr Cymru Welsh Water Ganol Overflow Afon Ganol 0 0h -

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

Annual figures up to and including 2025 come from official water company returns. The 2026 figure is our own estimate, derived continuously from the companies' live data feeds.

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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© 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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