Merthyr Tydfil and Aberdare - Live Sewage

Polluted by sewage 5,448 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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View Annual Sewage Data

You're looking at the totals that we have calculated for sewage in Merthyr Tydfil and Aberdare so far for 2026. It is an estimate, based on very poor quality live data from the Water Companies. The water companies report their sewage to the Environment Agency every year in April. You can see the last reported year in the other page

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Constituencies near Merthyr Tydfil and Aberdare

Daily Data

We get information about overflowing CSOs since January 2025. Here is a chart of the last three months of data for Merthyr Tydfil and Aberdare, here you can see overflows in red, the darker the red, the more the CSO overflowed that day.

Each CSO has a row, the most recent data is on the right hand side.

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Daily data is experimental and data is not guaranteed to be accurate. Please inform us of any issue, we will fix.
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Totals so far

Company CSO ID Overflow Days Total Duration (hours) Total Duration (days)
Dwr Cymru Welsh Water 43d4abbf78017ed395ef9359e55d6ae68b72d150f8869125abec0edef8dc5f72 38 820 h 45m 34.17
Dwr Cymru Welsh Water 75099f0f0c0a5e916fa7585afc3162f1452ab1845ea2f0997e8462db976b7f70 42 729 h 30m 30.38
Dwr Cymru Welsh Water 2d8a50b3986a1f277fda5735ee1eea596783062dd789802050e9a052c1b97018 34 717 h 5m 29.88
Dwr Cymru Welsh Water c8c99bd95528a109268bb11026bbc9a575053927a574955cf139e0645021dc62 31 541 h 45m 22.54
Dwr Cymru Welsh Water beb930c1705b3c2b45bae7907cd338483096bc3572e765750788c991df918b86 29 467 h 30m 19.46
Dwr Cymru Welsh Water aabad9141db4bf87ff2595a562c8e4feaa3e769c419828cb78ba41c543a425d5 26 278 h 44m 11.58
Dwr Cymru Welsh Water a7d4b435c81d74879406ef7feace773857db3f7ceef508f2e4c22d9ee01ef37f 27 237 h 3m 9.88
Dwr Cymru Welsh Water 13fdd42d4fd9aff5f5b1e4084be5ab8e37e4bcee0784e6df3444ed4f762e1dd8 26 195 h 8.12
Dwr Cymru Welsh Water 0cf3c39b569fce29261a17dfd76e2c35ad6034048132b05955b4a6ae4310ae23 21 174 h 13m 7.25
Dwr Cymru Welsh Water 2c536e6fc2f84f6b1794f085fd26854c16d48a1dad4d09ab0a343afa499ac290 15 139 h 23m 5.79
Dwr Cymru Welsh Water 07377751a00ed99f253d33df57e191affb6e3720de3f9fb3baae151b82091a60 23 122 h 5.08
Dwr Cymru Welsh Water be96f15d73ad085ee06aea6361edfd7415ca8cb8ea3060bc0702500fd1847b48 18 119 h 13m 4.96
Dwr Cymru Welsh Water 29b447c9a2ff6f8de682bece000878c84868d9c76207a1cbe48885414afd6dae 23 112 h 29m 4.67
Dwr Cymru Welsh Water 7f5479d162120a8396fa0f51895f11fd35c60cfaaf9af44abcb07ffb275bb512 22 108 h 4.5
Dwr Cymru Welsh Water e34a24a6779e7d1f532afcd6ba3bd2a59b2612432d4a26689273fa468b41a548 18 90 h 59m 3.75
Dwr Cymru Welsh Water 9bfd929a016236b8a919fe0e606331dc6694fde95f2b5d8dda7f2a376fa83cfd 11 90 h 23m 3.75
Dwr Cymru Welsh Water 32964b9aafff4265d4c694f1a2afb72540ee422c63cac5cb99ac967ea0c13357 18 72 h 3
Dwr Cymru Welsh Water 6583a8b0ce42e13dca348f797638a811b3f1c3f3dd98c47964055e196b074fbd 16 66 h 30m 2.75
Dwr Cymru Welsh Water 55166dd9e0fad51b0be32a11f71a9b6ef3150eac88cff6358ad843a753eb6f9b 5 56 h 30m 2.33
Dwr Cymru Welsh Water 6553b962a913187773b0bafae864c88b651db8ea17b9e6e58288207961125e3a 15 52 h 7m 2.17
Dwr Cymru Welsh Water 2459f5e7d16691a33634224e11b7866a17cc154cab3863ece23da8bc318052d6 19 51 h 30m 2.12
Dwr Cymru Welsh Water 999a1849b4b30d989f12a14e675e4bcb337b1da74d2b6380bfb1a777824a8f15 14 38 h 22m 1.58
Dwr Cymru Welsh Water 097a7678cea097a00230d5ce4a46f8d76436d4c01b98a9ee94e095c21d80c52a 10 25 h 35m 1.04
Dwr Cymru Welsh Water 7f6b8c7f22132bb54a740601176e4ea8a5cff3c438a046fc1d23ae6137ed7433 10 23 h 30m 0.96
Dwr Cymru Welsh Water a4d368aed9d1d00a5ace52ad42aa23cbff834783ecb0f67f72132cdad30e5e0d 7 15 h 42m 0.62
Dwr Cymru Welsh Water 6bdd11b3b4835bdf2073ebce8d234ac2bee818337f86ba6368852afe3c9586c5 6 12 h 44m 0.5
Dwr Cymru Welsh Water 6a0529c96b0600b8b1e66f4ddfc0f45439b7cb73bed530ce836431d224f38b96 7 10 h 38m 0.42
Dwr Cymru Welsh Water 7f044e3dc7a98159d6c3ac499f7e69f7a4d30b48ef547fa30c74bf19006b744d 5 9 h 27m 0.38
Dwr Cymru Welsh Water f454a849d8024620640cd6fff5866704526a1ebbd8adcbd7f68463e5a5d27c99 9 8 h 30m 0.33
Dwr Cymru Welsh Water db22a500a845018c9c757bb0db292f15d7eee4c4a08a99190261a5362adcd88a 6 7 h 10m 0.29
Dwr Cymru Welsh Water fe1696ffe02e993b380b2d2c57662f801b78380c663dfc67c8d5894e9657da37 8 6 h 57m 0.25
Dwr Cymru Welsh Water 8948d912de48361396d69390eb52855c0eabf2f18a304572e8be0fe6a6824374 10 6 h 12m 0.25
Dwr Cymru Welsh Water 3f912eb703d789bc16d20210350b7bf6917c4ccabe7148c8fc16793b18f31a8a 3 5 h 43m 0.21
Dwr Cymru Welsh Water f9e0b534009592d4e9e0a832ecb508c3ce8ba1fb3565f28ffa795aac0a531d4f 4 5 h 19m 0.21
Dwr Cymru Welsh Water ae250ef51830f1ec4f2f80577d2cc6825a9c61865a76a29726cd70c5d08ce097 5 3 h 42m 0.12
Dwr Cymru Welsh Water cc0c4b7f857b9b6e4e69682af3043de16b0be5a74493b29e0eaf0daff29cebab 5 3 h 13m 0.12
Dwr Cymru Welsh Water ff4e7d3f8533514838e254b0ed6fcf4d37babd06752d12e95a6db0cf34d55baa 5 2 h 43m 0.08
Dwr Cymru Welsh Water 13332eacc5e80ec7350f470e9124bdb0640f0a4174ca99163dbef2a63707a188 3 2 h 39m 0.08
Dwr Cymru Welsh Water 18f16074689a014d3510756df8d634717cfc2042aa97e32ce34435e6e2aa7a19 2 2 h 13m 0.08
Dwr Cymru Welsh Water f14e90566d86be2acc1fcda128227ee25d3b740521821b7f31b551a95b57650f 2 1 h 58m 0.04
Dwr Cymru Welsh Water 4d0425b0ece7f471de4589ce6659a130a32969458528ce5e5d7d2dec865682f3 2 1 h 45m 0.04
Dwr Cymru Welsh Water c8f3af38ed27e006cfb694244d282ae6f581cdee44838581c065c509e2ec2869 1 1 h 27m 0.04
Dwr Cymru Welsh Water 825acb91f05761a924bb2c03c6724d94380a621e3c65bbc5db3d3ff0ad959fbd 3 1 h 18m 0.04
Dwr Cymru Welsh Water d02d4b7363653f9bc9a7368ebfe8b22dfbd3d41602eb8b7e8a69f0c80d755d26 2 1 h 14m 0.04
Dwr Cymru Welsh Water 9a66282104eab637636db401143501b84116abefb098017bc11972664e18c11c 1 1 h 14m 0.04
Dwr Cymru Welsh Water 403472185a7a932bac3f080e4457c2d292bf37df1628279c632ec57bd9fd7705 3 1 h 9m 0.04
Dwr Cymru Welsh Water 88c9d0ebef7189b4a6498e6a966714a956775921dfd73dfd998a1a7e9bdce383 1 0 h 59m 0
Dwr Cymru Welsh Water d3c6fa6a22b5e93b7d7acfc1d6fac4c37178bb6fe9e04fe58b50fd34656fe10d 2 0 h 43m 0
Dwr Cymru Welsh Water 388419797580ae29b061dd0a6d0446369562956d275c677a35106b93ee455d9c 2 0 h 41m 0
Dwr Cymru Welsh Water 66d8425a92ba3cf8064c462e8318d0c26510ea20c338a2f385445a24a85d138a 1 0 h 29m 0
Dwr Cymru Welsh Water e13b7f7e2a32fe3e776a6d37f8be763af50cce9a3c9fb7cfe046a7595e17cf06 1 0 h 29m 0
Dwr Cymru Welsh Water 5a5f8e45f3f9407988646716a7921ae38437b52f11fcb858f785f090b4513028 1 0 h 29m 0
Dwr Cymru Welsh Water f29a93a99285205e66da5c724513d7e661fb49f5b18b0d1b85d7e68388b8489b 1 0 h 27m 0
Dwr Cymru Welsh Water 10ffdb921a5da818a895b2b62d19cd9c05b3fe41af33794f0f214ed949241ca1 1 0 h 17m 0
Dwr Cymru Welsh Water 3b8228c0e06f5db4a5fa85b3d904294a8c788f5fcac7f4e074ec4b54351396c9 1 0 h 15m 0
Dwr Cymru Welsh Water d20e00921e80887190a5965567fb60ccaa6bb3c9e9f4427f48a1ff222b74ba3e 1 0 h 15m 0
Dwr Cymru Welsh Water 4ad884c1aebc3b9501aad2c1f646813eb6d5c070795f4e62a90827a406440fa3 0 0 h 0
Dwr Cymru Welsh Water e3de1fa7cbb3fe55c31a9eb2f9a30a05e9bded054cbac26f7dd54e63822ab042 0 0 h 0
Dwr Cymru Welsh Water 41b68006a4efec389c183b1f1c0e360c58362679666a2429244cb81301799e6c 0 0 h 0
Dwr Cymru Welsh Water 59ae78eb6fba5bcb22bddd61446980bb424d35efd9a2f9c7225ccdac65b80e39 0 0 h 0
Dwr Cymru Welsh Water 0abbc7e60d9e91231638c98bd4140d8736b9b1230e0c86cc2be7ceed49be73e0 0 0 h 0
Dwr Cymru Welsh Water 4b6655567f447eecbe8c1d0e4c68d23a58350d08868f7c67e1b183973b195501 0 0 h 0
Dwr Cymru Welsh Water 3774d1e3a7f26c17a7280b0c2ec41d52e63f278c773d08b04bc9b091e7b664fc 0 0 h 0
Dwr Cymru Welsh Water 0f6692f40942429dae28cb12d81c0294e2de7b2693e3e7a1eb3b2ff3ff47ad83 0 0 h 0
Dwr Cymru Welsh Water d604713e1dae9dc28cb2a3709606489d8f575e9c34382e884444d56b1d46585c 0 0 h 0
Dwr Cymru Welsh Water 5fc67d1030280bdd30242a0ed0c0eade8140e2f32ad246d3fdc3f73f910bfdb5 0 0 h 0
Dwr Cymru Welsh Water e05e6fb6e90c8070fd8415d16a00def17a4a04d95ae587421f1ebf10f6e009b4 0 0 h 0
Dwr Cymru Welsh Water 0d6ab38ecc128e01fe42ee897a933076e717ad16afe24ea3352824f950ae5555 0 0 h 0
Dwr Cymru Welsh Water d433df21546ae95b970595e5ccf6e0019c7ef643fc1a3390c0a293ec76ebbce2 0 0 h 0
Dwr Cymru Welsh Water 709ace6b9a015dda5735005d19e1b2dcfc6f1fbefa72260cc846b9e2bcdb73b6 0 0 h 0
Dwr Cymru Welsh Water 0b5c347d2db9b32a62430ee5c0d9c894b425f268382e852facd41e09545bcc1a 0 0 h 0
Dwr Cymru Welsh Water 852d9b88904a8e4d4558f4033983ec90109bdb14832ab5e3f6875a4eebc22f16 0 0 h 0
Dwr Cymru Welsh Water aa730d8621984fb98f18ddcaf23f41d3bdd9da06fb2ce8b070a89243bfcbb076 0 0 h 0
Dwr Cymru Welsh Water fa777efac5e6d6fb0b2df36304d52b3c29c5d849c3a3c09702c1a431c981877d 0 0 h 0
Dwr Cymru Welsh Water c0e04537c326fa3e497e63d2d93d8e6f48aeaba702a151e6a6988a8d9e6a2fcf 0 0 h 0
Dwr Cymru Welsh Water 4a824d4b8560be3661c471b3f0b3531e4627fcf614c9284962e93b1639adb673 0 0 h 0
Dwr Cymru Welsh Water 1c034739a594573a1d9cfd0e3405411551f0ee26dbe654f6b61f893df558cdad 0 0 h 0
Dwr Cymru Welsh Water b8c8b6a86cbece30d67217cbc6af2cb1c9cd1e907063301299fb7e02a1bbaf5b 0 0 h 0
Dwr Cymru Welsh Water d282a85896804613188b1bae650d155d7e6ec4e0ec2eec9f93886f06df5f5673 0 0 h 0

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.

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