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Llyn Nantlle Uchaf polluted by sewage 68 times in 2025 - lasting 272 hours

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Totals for Llyn Nantlle Uchaf in 2025
1 Sites polluted by Dwr Cymru Welsh Water
68 sewage dumps
272 h duration
That's 1.62 weeks. 1.3 times a week, on average
Constituencies along Llyn Nantlle Uchaf
Places along Llyn Nantlle Uchaf

Pollution Summary 2025

Here are all the reported sewage overflow totals for Llyn Nantlle Uchaf 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 Llyn Nantlle Uchaf Nantlle No 5-CSO 68 272 98.7

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.

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