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Dwyfor Meirionnydd - 2025 Sewage

Polluted by sewage 79,430 hours in 2025 - That's 9.19 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 Dwyfor Meirionnydd 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 Dwyfor Meirionnydd

Daily Data

Jan - 0 hours
Feb - 3,001 hours
Mar - 677 hours
Apr - 1,651 hours
May - 650 hours
Jun - 2,243 hours
Jul - 823 hours
Aug - 666 hours
Sept - 8,167 hours
Oct - 5,602 hours
Nov - 25,281 hours
Dec - 30,562 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 Llan Ffestiniog WwTW Inlet Storm Overflow Nant Brisgyll 283 3,118h 45m -
Dwr Cymru Welsh Water Llangybi WwTW Overflow River Erch 164 3,115h 19m -
Dwr Cymru Welsh Water Blaenau Ffestiniog WwTW Point 1 Storm Overflow Afon Goedol 131 2,275h 25m -
Dwr Cymru Welsh Water Abererch WwTW Storm Overflow River Erch 117 2,247h 59m -
Dwr Cymru Welsh Water Beddgelert WwTW Storm Overflow River Glaslyn 137 2,108h 20m -
Dwr Cymru Welsh Water Fairbourne WwTW Storm Overflow Coastal Waters 102 2,024h 44m -
Dwr Cymru Welsh Water Four Crosses WwTW Storm Overflow River Erch 187 1,940h 4m -
Dwr Cymru Welsh Water Llanaelhaearn WwTW Overflow Unnamed Watercourse 197 1,923h 37m -
Dwr Cymru Welsh Water Chwilog WwTW Storm Overflow Afon Wen 112 1,786h 54m -
Dwr Cymru Welsh Water Trefor WwTW Relief Discharge Point Storm Overflow Unnamed Watercourse 124 1,651h 59m -
Dwr Cymru Welsh Water Nefyn Storm Overflow Caernarfon Bay 106 1,610h 28m -
Dwr Cymru Welsh Water Llithfaen WwTW Storm Overflow Rhyd Hir 78 1,552h 44m -
Dwr Cymru Welsh Water Criccieth WwTW Storm Overflow Tremadog Bay 89 1,492h 7m -
Dwr Cymru Welsh Water Llanllyfni WwTW Storm Overflow River Llynfi 109 1,491h 2m -
Dwr Cymru Welsh Water Llanelltyd Storm Overflow River Mawddach 75 1,396h 38m -
Dwr Cymru Welsh Water Llanrug WwTW Storm Overflow Afon Seiont 87 1,385h 29m -
Dwr Cymru Welsh Water Dolgellau WwTW Storm Overflow River Mawddach 77 1,229h 57m -
Dwr Cymru Welsh Water Llanystumdwy WwTW Settled Storm Overflow Dwyfor River 70 1,209h 5m -
Dwr Cymru Welsh Water Garndolbenmaen WwTW Storm Overflow Afon Dwyfor 77 1,190h 31m -
Dwr Cymru Welsh Water Station Road Pontrhythallt Storm Overflow River Seiont 105 1,155h 50m -
Dwr Cymru Welsh Water Waunfawr WwTW Storm Overflow Afon Gwyrfai 73 1,111h 58m -
Dwr Cymru Welsh Water Trawsfynydd WwTW Storm Overflow Afon Prysor 92 1,111h 32m -
Dwr Cymru Welsh Water Llanberis WwTW Storm Overflow Afon y Bala 97 937h 27m -
Dwr Cymru Welsh Water Corris WwTW Storm Overflow Afon Dulas 78 903h 36m -
Dwr Cymru Welsh Water Penmaenpool Bridge Storm Overflow River Mawddach 83 899h 26m -
Dwr Cymru Welsh Water B4418 Caernarfon Storm Overflow River Llynfi 64 895h 41m -
Dwr Cymru Welsh Water Dyffryn Ardudwy WwTW Storm Overflow Ardudwy Marsh Main Drain 62 879h 15m -
Dwr Cymru Welsh Water Aberdyfi Storm Overflow River Dyfi 47 874h 13m -
Dwr Cymru Welsh Water Llanfaglan WwTW Storm Overflow Afon Gwyrfai 65 869h 40m -
Dwr Cymru Welsh Water Harlech Main High Level Storm Overflow Unnamed Watercourse 46 862h 49m -
Dwr Cymru Welsh Water Efailnewydd WwTW Storm Overflow Unnamed Tributary of the Afon Rhyd Hir 91 841h 2m -
Dwr Cymru Welsh Water Cwm Bowydd Blaenau Ffestiniog Storm Overflow Afon Bowydd 92 827h 36m -
Dwr Cymru Welsh Water Penisarwaun WwTW Storm Overflow Afon Seiont 105 809h 34m -
Dwr Cymru Welsh Water Llan Ffestiniog WwTW Settled Storm Overflow Nant Brisgyll 93 804h 22m -
Dwr Cymru Welsh Water Mynytho WwTW Storm Overflow Unnamed Watercourse 86 780h 7m -
Dwr Cymru Welsh Water Bron Castell Storm Overflow Unnamed Watercourse 42 758h 26m -
Dwr Cymru Welsh Water Cambrian View Penrhyndeudraeth Storm Overflow Tributary of Afon Dwyryd 99 755h 3m -
Dwr Cymru Welsh Water Unknown Unknown 37 724h 23m -
Dwr Cymru Welsh Water Nefyn WwTW Inlet PS (Discharge Point A) Storm Overflow Afon Geirch 80 723h 53m -
Dwr Cymru Welsh Water Llanuwchllyn WwTW Overflow Afon Twrch 85 704h 9m -
Dwr Cymru Welsh Water Llannor WwTW Storm Overflow Afon Rhyd Hir 83 703h 39m -
Dwr Cymru Welsh Water Pentrefelin WwTW Storm Overflow Afon Cedron 59 693h 16m -
Dwr Cymru Welsh Water Maentwrog WwTW Storm Overflow River Dwyryd 52 692h 29m -
Dwr Cymru Welsh Water Lôn Goch Edern Storm Overflow Afon Geirch 60 681h 33m -
Dwr Cymru Welsh Water Llanystumdwy WwTW Storm Overflow Dwyfor River 64 661h 29m -
Dwr Cymru Welsh Water Talysarn Gas Works Storm Overflow Unnamed Tribuatary of Afon Llyfni 63 633h 54m -
Dwr Cymru Welsh Water Bontddu WwTW Storm Overflow Afon Cwmllechen 61 617h 13m -
Dwr Cymru Welsh Water Church Street Llanuwchllyn Storm Overflow River Dee 49 616h 55m -
Dwr Cymru Welsh Water Barmouth WwTW Long Sea Storm Overflow Cardigan Bay 136 579h 47m -
Dwr Cymru Welsh Water Glanypwll Road Storm Overflow Afon Barlwyd 112 574h 4m -
Dwr Cymru Welsh Water Bronaber WwTW Storm Overflow River Eden 63 546h 1m -
Dwr Cymru Welsh Water Llanbedrog Long Nant-Iago Storm Overflow Tremadog Bay 35 534h -
Dwr Cymru Welsh Water Stad Hafod Deiniolen Storm Overflow Afon Caledffrwd 104 532h 25m -
Dwr Cymru Welsh Water Castell Arthog Storm Overflow Unnamed Watercourse 40 522h 41m -
Dwr Cymru Welsh Water Pencefn Road Tanygrisiau Storm Overflow Afon Goedol 67 516h 24m -
Dwr Cymru Welsh Water Gellilydan WwTW Settled Storm Overflow Tributary of the Afon Tafarn Helyg 67 513h 43m -
Dwr Cymru Welsh Water South of River Bontnewydd Storm Overflow Afon Gwyrfai 73 504h 49m -
Dwr Cymru Welsh Water Corwen WwTW Storm Overflow River Dee 43 486h 3m -
Dwr Cymru Welsh Water Talysarn Bridge Storm Overflow Unnamed Tribuatary of Afon Llyfni 67 484h 35m -
Dwr Cymru Welsh Water Talsarnau WwTW Storm Overflow Unnamed Watercourse 53 469h 6m -
Dwr Cymru Welsh Water Bethel Storm Overflow Tributary of Afon Cadnant 48 459h 25m -
Dwr Cymru Welsh Water Pontllyfni No 3 Storm Overflow River Llyfni 35 455h 14m -
Dwr Cymru Welsh Water Taleymerau Pwllheli Storm Overflow Afon Rhyd Hir 57 445h 18m -
Dwr Cymru Welsh Water Llandrillo Storm Overflow Afon Ceidiog 69 436h 5m -
Dwr Cymru Welsh Water West Parade Criccieth Overflow Tremadog Bay 43 401h 29m -
Dwr Cymru Welsh Water Caernarfon Hen Gastell Storm Overflow Afon Carrog 60 393h 44m -
Dwr Cymru Welsh Water West Parade Criccieth Storm Overflow Tremadog Bay 32 384h 26m -
Dwr Cymru Welsh Water Bala WwTW Storm Overflow River Dee 61 379h 42m -
Dwr Cymru Welsh Water East Bank Afon Glaslyn Beddgelert Storm Overflow River Glaslyn 43 379h 16m -
Dwr Cymru Welsh Water Criccieth East Overflow Tremadog Bay 48 365h 28m -
Dwr Cymru Welsh Water Congl Y Wal Blaenau Ffestiniog Storm Overflow Storm Overflow Afon Ceunant Sych 35 361h 6m -
Dwr Cymru Welsh Water Tywyn WwTW Settled Storm Overflow Coastal Water - Cardigan Bay 67 356h 19m -
Dwr Cymru Welsh Water Arthog Terrace Storm Overflow Unnamed Watercourse 37 354h 33m -
Dwr Cymru Welsh Water Esplanade Criccieth Storm Overflow Tremadog Bay 27 333h 53m -
Dwr Cymru Welsh Water Nefyn WwTW Settled Storm Overflow Unnamed Tributary of Afon Geirch 25 327h 32m -
Dwr Cymru Welsh Water Tywyn WwTW Storm Overflow Dysynni Low Level Drainage Channel 60 326h 5m -
Dwr Cymru Welsh Water Clynnog Fawr Storm Overflow Unnamed Stream 54 313h 44m -
Dwr Cymru Welsh Water Llandanwg Station Storm Overflow Tremadog Bay 22 306h 43m -
Dwr Cymru Welsh Water Dolgellau Marian Mawr Storm Overflow River Wnion 76 291h 27m -
Dwr Cymru Welsh Water Caernarfon WwTW Storm Overflow Afon Seiont - Lower 71 272h 46m -
Dwr Cymru Welsh Water Outside Corwen WwTW Storm Overflow Unnamed Stream 63 267h 6m -
Dwr Cymru Welsh Water Glanrafon Bontnewydd Storm Overflow Afon Gwyrfai 28 264h 24m -
Dwr Cymru Welsh Water Caernarfon WwTW Storm Tank Storm Overflow Afon Seiont 24 263h 2m -
Dwr Cymru Welsh Water Bryncir WwTW Storm Overflow Afon Blaen-y-cae 40 249h 6m -
Dwr Cymru Welsh Water Point B Nefyn WwTW Inlet Storm Overflow River Ceirch 62 245h 45m -
Dwr Cymru Welsh Water Marian Mawr Dolgellau Storm Overflow Ffos Ddu 23 244h 5m -
Dwr Cymru Welsh Water Brynrefail Main Storm Overflow Afon Caledffrwd 41 242h 54m -
Dwr Cymru Welsh Water Llanllyfni Glan Aber Storm Overflow River Loughor 78 230h 17m -
Dwr Cymru Welsh Water Heulfryn Llanfaglan Storm Overflow Afon Carrog 62 223h 47m -
Dwr Cymru Welsh Water Rhiwlas WwTW Storm Overflow Afon Cegin 72 222h 2m -
Dwr Cymru Welsh Water Snowdon Street Storm Overflow Cyt Bach 58 210h 31m -
Dwr Cymru Welsh Water Nantlle No 5 Caernarfon Storm Overflow Llyn Nantlle Uchaf 46 206h 53m -
Dwr Cymru Welsh Water Cynwyd WwTW Storm Overflow River Dee 58 198h 31m -
Dwr Cymru Welsh Water Llwyngwril Storm Overflow Coastal Waters - Barmouth Bay 25 191h 49m -
Dwr Cymru Welsh Water Pen Y Cefn Road Storm Overflow River Wnion 38 181h 39m -
Dwr Cymru Welsh Water Rhosgadfan Storm Overflow Gwyrfai 43 178h -
Dwr Cymru Welsh Water Abergynolwyn WwTW Storm Overflow River Dysynni 28 172h 5m -
Dwr Cymru Welsh Water Carmel Groeslon Fields Storm Overflow Afon Llifon 52 170h 4m -
Dwr Cymru Welsh Water Morfa Bychan WwTW Storm Overflow Coastal Waters 39 162h 12m -
Dwr Cymru Welsh Water Aberdesach Storm Overflow Afon Desach 57 153h 11m -
Dwr Cymru Welsh Water Mill Lane Caernarfon Storm Overflow Afon Cadnant 66 151h 40m -
Dwr Cymru Welsh Water Llanwnda Storm Overflow Rhyd 38 150h 52m -
Dwr Cymru Welsh Water Fford Morfa Bychan Storm Overflow Tributary of Afon Glaslyn 58 144h 10m -
Dwr Cymru Welsh Water Caernarfon Seiont Bridge Storm Overflow River Seiont 15 139h 49m -
Dwr Cymru Welsh Water Hen Gei Llechi Felinheli Main Overflow Menai Strait 19 133h 20m -
Dwr Cymru Welsh Water Bryncoch Storm Overflow Unnamed Watercourse 12 130h 30m -
Dwr Cymru Welsh Water Llanberis Maes Padarn Storm Overflow Goch Bach 32 124h 27m -
Dwr Cymru Welsh Water Borth-Y-Gest Storm Overflow River Glaslyn 29 120h 16m -
Dwr Cymru Welsh Water Llwyn-y-gwalch Storm Overflow Afon Llifon 49 114h 46m -
Dwr Cymru Welsh Water Alyn Road Fairbourne Storm Overflow Afon Henddol 18 112h 59m -
Dwr Cymru Welsh Water Unknown Unknown 97 102h 55m -
Dwr Cymru Welsh Water North of River Bontnewydd Storm Overflow Afon Gwyrfai 37 102h 21m -
Dwr Cymru Welsh Water Abersoch Harbour Storm Overflow Afon Soch Estuary 10 101h 17m -
Dwr Cymru Welsh Water Dôl Eilian Llanberis Storm Overflow Afon Hwch 28 95h 25m -
Dwr Cymru Welsh Water Llanbedr WwTW Storm Overflow Afon Artro 23 82h 36m -
Dwr Cymru Welsh Water Llanegryn Street Storm Overflow River Dysynni 25 81h 58m -
Dwr Cymru Welsh Water Penrhos Camp WwTW Storm Overflow Afon Penrhos 28 81h 15m -
Dwr Cymru Welsh Water Tai Craig Y Don Cwm Y Glo Storm Overflow Unknown 14 80h 20m -
Dwr Cymru Welsh Water B4419 Caernarfon Storm Overflow Menai Strait 55 79h 18m -
Dwr Cymru Welsh Water Maes Gwyndy Trawsfynydd Storm Overflow Afon Prysor 43 69h 6m -
Dwr Cymru Welsh Water Idris Villas to NRA Storm Overflow Ditch 31 66h 10m -
Dwr Cymru Welsh Water Lombard Street Bank Place Porthmadog Storm Overflow Unnamed Stream 41 58h 37m -
Dwr Cymru Welsh Water Tan Y Buarth Bethel Storm Overflow Afon Cadnant 20 55h 56m -
Dwr Cymru Welsh Water Y Maes Pwllheli Storm Overflow Estuarial Waters of Afon Rhyd Hir 24 55h 49m -
Dwr Cymru Welsh Water Caernarfon Llanbeblig Road Storm Overflow Afon Seiont 30 53h 41m -
Dwr Cymru Welsh Water Aberdaron Storm Overflow Afon Daron 20 53h 39m -
Dwr Cymru Welsh Water Penygroes Storm Overflow River Llynfi 17 47h 27m -
Dwr Cymru Welsh Water Tremadog Iscraig Storm Overflow Y Cyt 11 46h 59m -
Dwr Cymru Welsh Water Unknown Unknown 5 44h 15m -
Dwr Cymru Welsh Water Porthmadog WwTW Final Effluent Overflow Glaslyn Estuary within Glaslyn Marshes 6 43h 33m -
Dwr Cymru Welsh Water Market Street Llanberis Storm Overflow Llyn Padarn 12 42h 6m -
Dwr Cymru Welsh Water Tregof Bethel Storm Overflow Afon Cadnant 11 39h 35m -
Dwr Cymru Welsh Water Pontllyfni STW Storm Overflow River Llyfni 18 37h 48m -
Dwr Cymru Welsh Water Glasfryn Terrace Storm Overflow Unnamed Watercourse 4 36h 45m -
Dwr Cymru Welsh Water Wesleyan Terrace Storm Overflow Unnamed Watercourse 5 34h 45m -
Dwr Cymru Welsh Water Porthmadog Britannia Place Storm Overflow River Glaslyn 4 34h 17m -
Dwr Cymru Welsh Water Penrhyndeudraeth WwTW Settled Storm Overflow River Dwyryd 6 31h 59m -
Dwr Cymru Welsh Water Margret Street Storm Overflow Afon Cadnant 37 31h 2m -
Dwr Cymru Welsh Water Trefor Storm Overflow Unnamed Stream 14 25h 44m -
Dwr Cymru Welsh Water Barmouth WwTW Short Sea Storm Overflow Cardigan Bay 16 21h 9m -
Dwr Cymru Welsh Water Fronwynion Street Trawsfynydd Storm Overflow Afon Prysor 11 18h 13m -
Dwr Cymru Welsh Water Llwyn Y Gell Road Ffestiniog Storm Overflow Barlwydd 11 17h 45m -
Dwr Cymru Welsh Water Friogg Storm Overflow Unnamed Watercourse 8 17h 3m -
Dwr Cymru Welsh Water Afonwen WwTW Storm Overflow Afon Wen 3 15h 15m -
Dwr Cymru Welsh Water Llandanwg Storm Overflow Tremadog Bay 2 14h 7m -
Dwr Cymru Welsh Water Aberdaron WwTW Storm Overflow Afon Cylch-y-Felin 12 13h 59m -
Dwr Cymru Welsh Water Ffordd Penllach Storm Overflow Unnamed Stream 13 13h 52m -
Dwr Cymru Welsh Water East Llanelltyd Storm Overflow River Mawddach 10 11h 51m -
Dwr Cymru Welsh Water North Western Road Blaenau Ffestiniog Overflow Afon Goedol 8 9h 25m -
Dwr Cymru Welsh Water Northern Terrace Corwen Storm Overflow River Dee 3 8h 28m -
Dwr Cymru Welsh Water Beach Bank Criccieth Storm Overflow Culverted stream which crosses Criccieth Beach 5 7h 42m -
Dwr Cymru Welsh Water Llanberis Road Storm Overflow Afon Cadnant 13 7h 25m -
Dwr Cymru Welsh Water Stryd Y Felin Storm Overflow Unnamed Watercourse 12 7h 5m -
Dwr Cymru Welsh Water A470 A4212 Junction Storm Overflow Unnamed Stream 11 6h 40m -
Dwr Cymru Welsh Water Barmouth Harbour Storm Overflow Mawddach Estuary 8 5h 26m -
Dwr Cymru Welsh Water Llanfachreth WwTW Storm Overflow Afon y Llan 8 4h 42m -
Dwr Cymru Welsh Water Clwt-y-bont Storm Overflow Afon Caledffrwd 4 4h 13m -
Dwr Cymru Welsh Water Porthmadog WwTW Site Drainage Overflow Glaslyn Estuary 3 2h 44m -
Dwr Cymru Welsh Water Minffordd Street Corris Storm Overflow River Deri 3 2h 12m -
Dwr Cymru Welsh Water Harlech Storm Overflow Tributary of Afon Dwyryd 7 2h 11m -
Dwr Cymru Welsh Water Porthmadog WwTW Tank Overflow Glaslyn Estuary 2 2h 4m -
Dwr Cymru Welsh Water Glan-Y-Don Pwllheli Storm Overflow River Erch 3 1h 56m -
Dwr Cymru Welsh Water Chapel Street Porthmadog Storm Overflow Nant Y Cyt 1 1h 29m -
Dwr Cymru Welsh Water Maentwrog Storm Overflow River Dwyryd 4 1h 13m -
Dwr Cymru Welsh Water Mawddach Crescent Storm Overflow Mawddach Estuary 2 0h 57m -
Dwr Cymru Welsh Water Ysgoldy Storm Overflow Afon Cadnant 3 0h 52m -
Dwr Cymru Welsh Water Amanda Terrace Storm Overflow River Glaslyn Estuary 2 0h 30m -
Dwr Cymru Welsh Water Caernarfon WwTW Inlet Storm Overflow River Seiont 2 0h 30m -
Dwr Cymru Welsh Water Chandlers Place Porthmadog Storm Overflow Nant Y Cyt 1 0h 29m -
Dwr Cymru Welsh Water Rhedyw Road Llanllyfni Overflow River Llynfi 2 0h 29m -
Dwr Cymru Welsh Water St. Mary's Terrace Storm Overflow Unnamed Watercourse 1 0h 15m -
Dwr Cymru Welsh Water The Square Blaenau Ffestiniog Storm Overflow Afon Bowydd 1 0h 15m -
Dwr Cymru Welsh Water A496 Llanbedr Storm Overflow Culvert to Afon Artro 1 0h 15m -
Dwr Cymru Welsh Water Abererch Road Crossing Storm Overflow River Erch 0 0h -
Dwr Cymru Welsh Water Crown Street Caernarfon Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Bryncrug Overflow Afon Fathew 0 0h -
Dwr Cymru Welsh Water Glan Y Mor Felinheli Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Morfa Bychan WwTW High-level Storm Overflow Unnamed Stream 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Waterloo Port Road Storm Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Castle Ditch Storm Overflow Afon Seiont 0 0h -
Dwr Cymru Welsh Water Bank Quay Caernarfon Storm Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Afon Angell Bridge Aberangell Storm Overflow Afon Angell 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Balaclava Road Caernarfon Storm Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Blaenau Ffestiniog WwTW Point 2 Storm Overflow Afon Bowydd 0 0h -
Dwr Cymru Welsh Water Bridge on A499 Pontllyfni Overflow River Llyfni 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 0 0h -
Dwr Cymru Welsh Water Port Terrace Felinheli Overflow Menai Strait 0 0h -
Dwr Cymru Welsh Water Corwen Clawdd Poncefn Storm Overflow Tributary of River Dee 0 0h -
Dwr Cymru Welsh Water Unknown Unknown 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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Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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