This is a sewage discharge monitoring station, which is usually a type of Event Duration Monitor (EDM). These stations themselves are designed to mitigate the impact of heavy rainfall by discharging, under permitted conditions, any overflow into a water body. They are often actively discharging during flood events. This page presents the data acquired by the monitoring system for this discharge station.
Sewage Reports that include this Station
Operational Summary - 2021-2023
Cwm-Llechen | 355 Spills | 4275.5 hours | 16.26
The declared body of water receiving this discharge is the "Cwm-Llechen" This station has discharged sewage 355 time(s). The station has discharged for a total of 4275.5 hour(s). This is 16.26% of the time which we have data for. In total: 178 day(s)* of elapsed time.
99.3 | 175.2 hours This monitor has been operational for 99.3% of its total time we have data for. There are 175.2 hours unaccounted for due to downtime of the monitor.
The worst year in our records for the "Bontddu STW" is 2023, discharging sewage for 1569.7 hours of the year.
Uptimes below 90% (red line) should be accompanied by a reason
*This is total time in days, not individual days.
Yearly Summary
Most Recent Year - 2023
Cwm-Llechen | 126 Spills | 1569.7 hours | 17.91 The declared body of water receiving this discharge is the "Cwm-Llechen" This station discharged sewage 126 time(s) during 2023. The station discharged for a total of 1569.7 hour(s). This is around 65 day(s)* or 17.91% of the year.
99.9 | 3.5 hours This monitor was operational for 99.9% of the year. Leaving 3.5 hours unaccounted for in the data.
*This is total time in days, not individual days of the year.
Permit & Governance
Attribute
Value
Governing Body
Natural Resources Wales
Operator
Dwr Cymru Welsh Water
Primary Permit #
CG0139002
Secondary Permit #
CG0139002
2022
Cwm-Llechen | 106 Spills | 1202 hours | 13.72 The declared body of water receiving this discharge is the "Cwm-Llechen" This station discharged sewage 106 time(s) during 2022. The station discharged for a total of 1202 hour(s). This is around 50 day(s)* or 13.72% of the year.
100 | 0 hours This monitor was operational for 100% of the year. Leaving 0 hours unaccounted for in the data.
*This is total time in days, not individual days of the year.
Permit & Governance
Attribute
Value
Governing Body
Natural Resources Wales
Operator
Dwr Cymru Welsh Water
Primary Permit #
CG0139002
Secondary Permit #
CG0139002
2021
Afon Cwmllechen | 123 Spills | 1503.7 hours | 17.16 The declared body of water receiving this discharge is the "Afon Cwmllechen" This station discharged sewage 123 time(s) during 2021. The station discharged for a total of 1503.7 hour(s). This is around 62 day(s)* or 17.16% of the year.
99.9 | 5.2 hours This monitor was operational for 99.9% of the year. Leaving 5.2 hours unaccounted for in the data.
*This is total time in days, not individual days of the year.
Permit & Governance
Attribute
Value
Governing Body
Natural Resources Wales
Operator
Dwr Cymru Welsh Water
Primary Permit #
CG0139002
Secondary Permit #
CG0139002
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