Top of the Poops | Place | Y Coed Duon | Polluted by Dwr Cymru Welsh Water

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Totals for Y Coed Duon in 2025

17 Sites polluted by Dwr Cymru Welsh Water

738 sewage dumps

3,183 hours duration

That's 4.42 months. On average 2 times a day

Change Over Time

Constituency for Y Coed Duon

Nearby Constituencies

Waterways in Y Coed Duon

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Pollution Summary 2025

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

Reporting refers to how much of the time the monitoring was active. In this place all the declared CSO Combined Sewage Overflow - a device that, when operating, pours combined rainwater & sewage into a waterway s appeared to have monitoring enabled for more than 50% of the year

Company	Waterway	Site	Sewage Dumps	Duration (Hours)	Reporting %
Dwr Cymru Welsh Water	River Rhymney	CSO at Glan-yr-Afon Nursing Home No2, Pengam	110	1,203	98.9
Dwr Cymru Welsh Water	River Sirhowy	Springfield Est CSO, Pontllanfraith	83	489	97.1
Dwr Cymru Welsh Water	River Rhymney	CSO at Glan-yr-Afon Nursing Home 1	69	253	100
Dwr Cymru Welsh Water	River Rhymney	CSO at Pengham High St near Bridge	49	206	100
Dwr Cymru Welsh Water	Sirhowy River	Blackwood Cwmgelli CSO	66	205	99.4
Dwr Cymru Welsh Water	River Rhymney	Tir-y-Berth behind William St	63	192	99.2
Dwr Cymru Welsh Water	River Rhymney	TRELYN LANE CSO FLEUR-DE-LIS	37	130	99.8
Dwr Cymru Welsh Water	River Sirhowy	Old Tram Rd CSO, Pontllanfraith	36	112	97.2
Dwr Cymru Welsh Water	Sirhowy River	Blackwood Oakdale Rhiw Hill CSO	41	105	89.2
Dwr Cymru Welsh Water	River Sirhowy	CSO 16 Woodfield Row Blackwood	25	63	99.9
Dwr Cymru Welsh Water	River Rhymney	CSO Opposite Bowen Ind Estate, Aberbargoed	36	60	99.7
Dwr Cymru Welsh Water	River Sirhowy	Blackwood 100 Steps CSO	37	57	97.6
Dwr Cymru Welsh Water	River Rhymney	CSO at rear of Margaret St., Gilfach	24	44	96.9
Dwr Cymru Welsh Water	River Rhymney	CSO ASSET NO 90411 PENGAM	40	36	96.9
Dwr Cymru Welsh Water	River Rhymney	High St CSO, Glan-y-Nant	12	18	99.8
Dwr Cymru Welsh Water	Rhymney R - Nant Bargod Rhymni To Conf Nant Cyl	Fleur-de-Lys - Rear of Glanddu CSO	6	3	99.6
Dwr Cymru Welsh Water	River Rhymney	CSO at Trelyn Park	4	1	99.9
Dwr Cymru Welsh Water	River Rhymney	Rear of Williams St CSO	0	0	100

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.

Analysing sewage pollution by the Water Industry

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Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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