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River Tywi polluted by sewage 614 times in 2025 - lasting 6,917 hours

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Contains OS Data © Crown copyright & database right 2021-2024
© Top of the Poops 2021-2024
Totals for River Tywi in 2025
7 Sites polluted by Dwr Cymru Welsh Water
614 sewage dumps
6,917 h duration
That's 9.61 months. On average 1.7 times a day
Constituencies along River Tywi
Places along River Tywi

Pollution Summary 2025

Here are all the reported sewage overflow totals for River Tywi in 2025. Sometimes sewage can be being dumped for months at a time.

Company Waterway Site Sewage Dumps Duration (Hours) Reporting %
Dwr Cymru Welsh Water River Tywi Cwm Ifor Wastewater Treatment Works 142 2,349 99.9
Dwr Cymru Welsh Water River Tywi FFAIRFACH STW 158 2,161 99.9
Dwr Cymru Welsh Water River Tywi Ashfield Road P.S. Ashfield Llangado 51 874 93.8
Dwr Cymru Welsh Water River Tywi CSO Pothouse Wharf PS 102 609 99.8
Dwr Cymru Welsh Water River Tywi Llansadwrn SPS 54 593 98.2
Dwr Cymru Welsh Water River Tywi LLANDEILO CSO 105 300 98.3
Dwr Cymru Welsh Water River Tywi Park Hinds CSO 2 29 99.9

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.