Ynys Môn polluted by sewage 2,878 times in 2022 - lasting 18,813 hours

© OpenStreetMap contributors
Contains OS Data © Crown copyright & database right 2021-2022
© Top of the Poops 2021-2023
✔ means we have experimental daily data for 2023
Totals for Ynys Môn in 2022
72 Sites polluted by Dwr Cymru Welsh Water
2,878 sewage dumps
18,813 h duration
That's 2.18 years! On average 7.9 times a day
Constituencies near Ynys Môn

Pollution Summary 2022

Here are all the reported sewage overflow totals for Ynys Môn in 2022. Sometimes sewage can be being dumped for months at a time.

Company Waterway Site Sewage Dumps Duration (Hours) Reporting %
Dwr Cymru Welsh Water Menai Strait PS NO 3 (SUSPENSION BRIDGE) (EMERGE 109 1,640 100
Dwr Cymru Welsh Water Menai Strait PS NO 3 (SUSPENSION BRIDGE) (EMERGE 109 1,640 100
Dwr Cymru Welsh Water Unnamed Watercourse To River Goch Rhosybol Gorslwyd PS 110 1,354 99.5
Dwr Cymru Welsh Water Ditch Hermon Malltraeth PS 72 1,067 95.3
Dwr Cymru Welsh Water Unnamed Draining To New Harbour Porth y Felin Sewage Pumping Station 87 972 96.6
Dwr Cymru Welsh Water River Meddanen LLANFECHELL PUMPING STATION 68 926 100
Dwr Cymru Welsh Water Cadnant PONT LLANDEGFAN SEWAGE PUMPING STAT 63 897 96.6
Dwr Cymru Welsh Water Menai Strait LLANDEGFAN (MENAI) PUMPING STATION 54 794 100
Dwr Cymru Welsh Water Un-Named Watercourse VALLEY STORM PS (GRAVITY DISCHARGE) 79 750 99.6
Dwr Cymru Welsh Water Menai Strait BRYNSCIENCYN STW 74 744 100
Dwr Cymru Welsh Water Abberffraw Bay ABERFFRAW WASTE WATER TREATMENT WKS 185 565 80.1
Dwr Cymru Welsh Water River Nodwydd PENTRAETH STW 67 541 100
Dwr Cymru Welsh Water Estuarial Waters Of Holy Island Strait South Four Mile Bridge SPS Holyhead 35 487 100
Dwr Cymru Welsh Water Unnamed Stream VALLEY DYFFRYN AND PENDYFFRYN 23 461 100
Dwr Cymru Welsh Water Menai Strait MOUNT FIELD P.S. BEAUMARIS , 86 426 93
Dwr Cymru Welsh Water Bull Bay Bull Bay P.S. 70 352 99.5
Dwr Cymru Welsh Water Coastal Waters BENLLECH WWTW (STW) LSO BENLLECH 63 343 100
Dwr Cymru Welsh Water River Cadnant Gorsllwyd Sewage Pumping Station 60 340 100
Dwr Cymru Welsh Water Menai Strait Llanfair PG WwTW CSO 103 323 98.8
Dwr Cymru Welsh Water Menai Strait PS NO 1 (FAELOG CAUSEWAY) (EMERGENC 52 292 100
Dwr Cymru Welsh Water Menai Strait PS NO 1 (FAELOG CAUSEWAY) (EMERGENC 52 292 100
Dwr Cymru Welsh Water Irish Sea RHOSNEIGR SPS RHOSNEIGR 22 263 100
Dwr Cymru Welsh Water Menai Strait LLANFAES WWTW STORM TANK 39 260 98.9
Dwr Cymru Welsh Water Braint Gaerwen Station SPS 35 252 99.1
Dwr Cymru Welsh Water River Briant LLANDDANIEL PONT Y CRUG SPS 32 243 98.6
Dwr Cymru Welsh Water Unnamed Stream GWALCHMAI ISAF PS 29 209 41
Dwr Cymru Welsh Water Un-Named Watercourse HOLYHEAD WWTW FINAL EFFLUENT PS 105 177 100
Dwr Cymru Welsh Water Esturial Waters Of Inland Sea TREARDDUR BAY PS (PUMPED DISCHARGE) 57 172 99.8
Dwr Cymru Welsh Water Old Harbour Holyhead Wastewater Treatment Works SPS 64 159 100
Dwr Cymru Welsh Water Outer Harbour, Holyhead Morawelon SPS 41 156 99.6
Dwr Cymru Welsh Water Un-Named Watercourse Valley Storm PS (Pumped Discharge) 52 148 99.6
Dwr Cymru Welsh Water New Harbour Coastguard CSO 82 120 100
Dwr Cymru Welsh Water Un-Named Watercourse TREARDDUR BAY PS (GRAVITY) 31 118 99.4
Dwr Cymru Welsh Water Menai Strait LLEINIOG PS 30 105 41.2
Dwr Cymru Welsh Water Alan Catchment RHOSYBOL PLAS Y FFRWD SPS 22 98 100
Dwr Cymru Welsh Water Cefni - Cefni Reservoir West Lon Sardis CSO (BODFFORDD OPP CAPEL SARDIS) 68 87 100
Dwr Cymru Welsh Water River Goch Storm Tank Army Cadet Centre CSO 30 67 98
Dwr Cymru Welsh Water Unnamed Stream Llangaffo STW CSO 66 65 100
Dwr Cymru Welsh Water Menai Strait WEST END PS BEAUMARIS ANGLESEY 22 64 100
Dwr Cymru Welsh Water Estuarial Waters Of River Alaw Gorad PS Gorad NR Valley Anglesey 22 60 99.3
Dwr Cymru Welsh Water Adjacent Ditch Llangefni Rhostrehwfa CSO 13 59 100
Dwr Cymru Welsh Water Coastal Waters MOELFRE PS MOELFRE 12 58 100
Dwr Cymru Welsh Water River Goch Craig Y Don SPS 7 55 8.2
Dwr Cymru Welsh Water River Cefni Llangefni Main Pumping Station 9 47 99.9
Dwr Cymru Welsh Water Coastal Waters Of Irish Sea CEMAES PS/BALANCING TANK CEMAES BAY 15 43 99.9
Dwr Cymru Welsh Water Unnamed Ditch LLANGAFFO CAE BERLLAN SPS 5 43 99.7
Dwr Cymru Welsh Water Braint LLANFAIR PG SPS 21 41 100
Dwr Cymru Welsh Water Coastal Waters - Amlwch Harbour Amlwch Port CSO 34 39 100
Dwr Cymru Welsh Water River Braint NEWBOROUGH STW 19 38 98.4
Dwr Cymru Welsh Water Llyn Maelog BRYN DU SEWAGE PUMPING STATION 9 34 99.7
Dwr Cymru Welsh Water Menai Strait GLYN GARTH PS LLANDEGFAN 20 29 100
Dwr Cymru Welsh Water Unnamed Watercourse LLANFAES PS (EMERGENCY) , , 4 24 99.9
Dwr Cymru Welsh Water New Harbour Hibernia Row Pumping Station 2 24 100
Dwr Cymru Welsh Water Cefni Estuary MALLTRAETH WWTW - STORM 40 23 99.5
Dwr Cymru Welsh Water Cefni Reservoir By-Pass Channel Bodffordd STW Settled Storm 13 23 100
Dwr Cymru Welsh Water Cefni CSO Llangefni MH Front Ynys Mon Of 36 22 99.6
Dwr Cymru Welsh Water Menai Strait BRYNSCIENCYN PS 6 22 100
Dwr Cymru Welsh Water Menai Strait RHIANFA PS LLANDEGFAN 17 22 82.9
Dwr Cymru Welsh Water Menai Strait BRYNSCIENCYN PS , , 6 21 100
Dwr Cymru Welsh Water Unnamed Ditch TALWRN SPS 18 20 100
Dwr Cymru Welsh Water River Cefni LLANGEFNI WWTW STORM OVERFLOW 33 17 99.4
Dwr Cymru Welsh Water Y Brenin PONT Y BRENIN PS 9 12 99.7
Dwr Cymru Welsh Water Cadnant LLANSADWRN PS 3 10 96.2
Dwr Cymru Welsh Water Coastal Waters CYNLAI PS LLANGOED ANGLESEY 4 9 98.6
Dwr Cymru Welsh Water Via A Drainage To River Clai CSO at Llangefni MH Rear of Burgess 14 7 99.9
Dwr Cymru Welsh Water Coastal Waters WENDON CAR PARK PS BENLLECH , , , 6 4 100
Dwr Cymru Welsh Water Braint DWYRAN RHYDWYN - SSO 13 4 81.6
Dwr Cymru Welsh Water River Goch Settled Storm Tank at Llanerchymedd STW 3 3 100
Dwr Cymru Welsh Water Nant Cwyrtai GWALCHMAI STW 6 2 100
Dwr Cymru Welsh Water New Harbour, Holyhead WATERSIDE PUMPING STATION 7 2 100
Dwr Cymru Welsh Water Cefni Estuary MALLTRAETH WWTW TERMINAL 2 1 99.5
Dwr Cymru Welsh Water Nodwydd PENTRAETH TAN Y GRAIG SPS 2 0 100
Dwr Cymru Welsh Water Unnamed Ditch FRYARS BAY P.S- SCREENED EMERG 0 0 100
Dwr Cymru Welsh Water River Alaw Bodedern Sewage Pumping Station 0 0 100
Dwr Cymru Welsh Water Eastuary - River Cefni MALLTRAETH VILLAGE PUMPING STATION 0 0 0
Dwr Cymru Welsh Water Cefni MALLTRAETH VILLAGE CSO 0 0 0
Dwr Cymru Welsh Water Coastal Waters RHOSNEIGR STW (SETTLED STORM/EMERGE 0 0 46.1
Dwr Cymru Welsh Water Menai Strait LLYN Y FELIN PS (EMERGENCY) 0 0 99.4
Dwr Cymru Welsh Water Menai Strait PS NO 2 (PORTH WRACH) (EMERGENCY) 0 0 100
Dwr Cymru Welsh Water River Alaw Newlands Beach PS Valley Angle 0 0 99.9
Dwr Cymru Welsh Water River Cadnant LLANSADWRN PS 0 0 80.4
Dwr Cymru Welsh Water Coastal Waters Llaneilian SPS 0 0 0
Dwr Cymru Welsh Water Braint DWYRAN BY SCHOOL - SSO 0 0 0
Dwr Cymru Welsh Water Of Braint LLANFAIRPWLL SSO NO. 2 0 0 0
Dwr Cymru Welsh Water Menai Strait PS NO 2 (PORTH WRACH) (EMERGENCY) 0 0 100
Dwr Cymru Welsh Water Beddmanarch Bay PENRHOS BEACH PUMPING STATION 0 0 100
Dwr Cymru Welsh Water Adj Ditch TREARDDUR BAY HAUL A MOR SPS 0 0 100
Dwr Cymru Welsh Water River Cefni Gaerwen WWTW Settled Storm 0 0 100
Dwr Cymru Welsh Water Menai Strait LLYN Y FELIN PS (EMERGENCY) , , 0 0 99.4
Dwr Cymru Welsh Water Unnamed Ditch NEWBOROUGH MILLBANK SPS 0 0 0
Dwr Cymru Welsh Water River Ffraw ABERFFRAW SPS GLAN Y MOR ABERFFRAW 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

Experimental derived data from Thames Water API, Some data may be missing or inaccurate. This 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.