Area of Outstanding Natural Beauty

Clwydian Range & Dee Valley - Live Sewage

Polluted by sewage 2,315 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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Totals for Clwydian Range & Dee Valley in 2026

Sewage2,315 hours
Monitoring offline0 hours
Potential pollution0 hours
Storm overflows23

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Daily Data - when it rained, and when they spilled

Square = rainfall none → heavy
Drop = sewage minutes → all day
Potential pollution Monitoring offline
Jan - 765 hours
Feb - 1,123 hours
Mar - 258 hours
Apr - 2 hours
May - 8 hours
Jun - 0 hours
Jul - 0 hours
Aug - 29 hours
Sept - 21 hours
Oct - 102 hours
Nov - 2 hours

Storm overflows in and around Clwydian Range & Dee Valley

Company Site Name Receiving Waterway Overflow Days Total Duration (hours) Offline/Potential Pollution
Dwr Cymru Welsh Water Corwen WwTW Storm Overflow River Dee 72 810h 14m -
Dwr Cymru Welsh Water Llangollen WwTW Storm Overflow River Dee 45 637h 15m -
Dwr Cymru Welsh Water Cefn Mawr WwTW Storm Overflow River Dee 35 290h 1m -
Dwr Cymru Welsh Water Llanarmon Yn Ial WwTW Overflow River Alyn 37 146h 16m -
Dwr Cymru Welsh Water Cefn Storm Overflow Tref-Y-Nant Brook 33 124h 26m -
Dwr Cymru Welsh Water Outside Corwen WwTW Storm Overflow Unnamed Stream 14 108h 9m -
Dwr Cymru Welsh Water Llangollen Queen Street Storm Overflow River Cyflymen 20 59h 12m -
Dwr Cymru Welsh Water Bridge Street No 2 Storm Overflow River Dee 20 44h 57m -
Dwr Cymru Welsh Water Off Church Terrace Llandegla Storm Overflow River Alyn 12 41h 13m -
Dwr Cymru Welsh Water Llanferres Storm Overflow Tributary of Afon Alun 5 31h 45m -
Dwr Cymru Welsh Water Abbey Road Storm Overflow River Dee 11 13h 11m -
Dwr Cymru Welsh Water Next to Bridge Newbridge Overflow River Dee 3 3h 14m -
Dwr Cymru Welsh Water Church Road Minera Storm Overflow Afon Clywedog 3 2h 44m -
Dwr Cymru Welsh Water Berwyn Street Storm Overflow River Dee via surface water sewer 1 1h -
Dwr Cymru Welsh Water Bridge Street Storm Overflow No1 River Dee 1 0h 45m -
Dwr Cymru Welsh Water Park Avenue Storm Overflow River Dee 1 0h 45m -
Dwr Cymru Welsh Water Llangollen Church Street Storm Overflow River Dee 1 0h 15m -
Dwr Cymru Welsh Water Llangollen Riverside Park Storm Overflow River Dee 0 0h -
Dwr Cymru Welsh Water Llangollen East Street Storm Overflow River Dee 0 0h -
Dwr Cymru Welsh Water Nannerch Storm Overflow Tributary of River Wheeler 0 0h -
Dwr Cymru Welsh Water Llangollen Victoria Prom Storm Overflow River Dee 0 0h -
Dwr Cymru Welsh Water Llangollen West Street Storm Overflow River Dee 0 0h -
Dwr Cymru Welsh Water Northern Terrace Corwen Storm Overflow River Dee 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.