Llanfynydd WwTW Storm Overflow

Storm overflow run by Dwr Cymru Welsh Water, discharging into Afon Sannen.

Storm Overflow
Right now
Not discharging
Last discharge ended 13:22 on 30 Sep 2026 (54 min ago).
Times are UK time · company feed updated 8 min ago

"Not discharging" means the company's monitor reports no discharge right now — not that the water is clean. The feed publishes status only; no discharge volume is measured.

2026 so far
6spills
34 h discharging on 6 days · live feed since 28 Feb, not yet official
2025 official
169spills
1,845 h · −24% on 2024
Rank in Dwr Cymru Welsh Water
—
No ranking for this overflow.
Monitor in 2025
99.9% working
Share of the year the monitor reported

Year by year

Dŵr Cymru Welsh Water's annual Event Duration Monitoring return to Natural Resources Wales (12/24-hour spill count), as compiled by The Rivers Trust. 2026 is our own running count, the same way, from the live feed since 28 February (when we began keeping every discharge it reports) — so it can only be lower than the full year. The official figure is published next spring.

2022
173 spills · 1,738 hmonitor 100%
2023
233 spills · 3,363 hmonitor 100%
2024
222 spills · 2,862 hmonitor 99.6%
2025
169 spills · 1,845 hmonitor 99.9%
2026since 28 Feb
6 spills · 34 h

"No data" means the monitor was not working or not required to report that year — not zero.

Discharges we have recorded

2,519 discharge periods since 2 Jan 2020. 2,511 of them come from Dwr Cymru Welsh Water's own event-duration-monitoring records (published by the company, Jan 2020 – Dec 2025); the live feed adds anything after that. The official annual count is the figure to quote.

Show 30 earlier (of 2,519)
Started (UK time)EndedDischarge time
27 Dec 2025, 08:0008:3030 min
27 Dec 2025, 01:1501:4530 min
26 Dec 2025, 17:4518:1530 min
8 Dec 2025, 09:3011:1514 d 1 h
2 Dec 2025, 09:3008:305 d 23 h
26 Nov 2025, 14:3010:304 d 19 h
26 Nov 2025, 13:0013:4530 min
26 Nov 2025, 12:1512:3015 min
26 Nov 2025, 11:0011:1515 min
26 Nov 2025, 10:0010:1515 min
26 Nov 2025, 08:4509:1530 min
26 Nov 2025, 07:4508:0015 min
26 Nov 2025, 07:0007:1515 min
26 Nov 2025, 06:1506:3015 min
25 Nov 2025, 21:3022:3045 min
25 Nov 2025, 19:4521:0045 min
24 Nov 2025, 08:3019:151 d 10 h
20 Nov 2025, 01:0011:1510 h 15 min
19 Nov 2025, 20:3023:152 h 45 min
19 Nov 2025, 06:1518:1512 h 0 min
19 Nov 2025, 02:4503:3045 min
18 Nov 2025, 23:1500:0045 min
18 Nov 2025, 19:0019:1515 min
18 Nov 2025, 14:3015:0030 min
18 Nov 2025, 10:0010:1515 min
18 Nov 2025, 06:4508:452 h 0 min
18 Nov 2025, 05:0005:3030 min
18 Nov 2025, 03:0003:4545 min
17 Nov 2025, 17:0000:007 h 0 min
10 Nov 2025, 20:3016:156 d 19 h

The year figures above use the EA's 12/24-hour counting method, so they are comparable with the official figures; the monitor log's 2,739 raw blocks were merged into 2,519 continuous discharge periods (gaps under 15 min joined).

Rain nearby last 30 days

Nearest live rain gauge: Abergorlech Raingauge, 7.3 km away. Brown shading = when this overflow was discharging; ▼ = a discharge start.

Overflow shading is a timing match, not proof of cause — heavy rain and spills share a trigger. Times come from the water company’s event-duration monitor (site status only; no discharge volume is published).

Where it is

Nearest river gauge
Felin Mynachdy River Station (Cloidach) · 6.6 km
Nearest rain gauge
Site reference
DCWW1539
Coordinates
51.92373, -4.10044

Concerned about this overflow?

Report pollution you can see or smell to the regulator straight away; the company handles complaints about the overflow itself.

Live status: © Dŵr Cymru Welsh Water, from its Storm Overflow Map. Spill-event history: © Dŵr Cymru Welsh Water's published EDM start/stop records. Annual figures: The Rivers Trust EDM compilation, © Dŵr Cymru/Welsh Water, Open Government Licence. Times are shown in UK local time. FloodRadar republishes the monitor's status; it does not measure discharges itself.