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River Marlais polluted by sewage 575 times in 2025 - lasting 9,239 hours

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Contains OS Data © Crown copyright & database right 2021-2024
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Totals for River Marlais in 2025
6 Sites polluted by Dwr Cymru Welsh Water
575 sewage dumps
9,239 h duration
That's 12.83 months. On average 1.6 times a day

Pollution Summary 2025

Here are all the reported sewage overflow totals for River Marlais 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 Marlais CSO 6 NR BRYN MARLAIS FARM 188 3,335 95.1
Dwr Cymru Welsh Water River Marlais CARMEL WWTW CARMEL 161 3,017 99.9
Dwr Cymru Welsh Water River Marlais CSO 4 Manhole 225A Adj 3 Rawlings 51 973 99.7
Dwr Cymru Welsh Water River Marlais CSO at Narberth East SPS 69 913 99.9
Dwr Cymru Welsh Water River Marlais 29 Aberlash Rd CSO, Llandybie 61 871 99.4
Dwr Cymru Welsh Water River Marlais Llandybie RFC CSO 45 127 99.5
Dwr Cymru Welsh Water River Marlais LLANSAWEL WWTW 0 0 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.