Harthill WwTW CSO
Storm overflow run by Scottish Water, discharging into How Burn.
"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.
Year by year
Scottish Water's published data for monitored overflows (number of overflow events; Scottish Water does not use the 12/24-hour count). 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.
"No data" means the monitor was not working or not required to report that year — not zero. Scottish Water counts each overflow event; England and Wales count 12/24-hour "spills", so these numbers are not directly comparable with English or Welsh overflows.
Twin outlet
Scottish Water runs another overflow within 300 m that also discharges into How Burn. They share the sewer and the storm, so one outlet's figures are only part of what reaches the water.
This overflow: 187 spills in 2025. Distances are between the published outlet points.
Downstream of this overflow
The next gauge downstream that the river map places is Whitburn (Almond (Lothian)), 4.6 km along the river.
A river gauge measures the level of the river; it does not measure this overflow's discharge, and a spill does not by itself explain a change there. Traced on OS Open Rivers (edition 2026-04), which leaves out many small channels.
Contains OS data © Crown copyright and database rights 2026.
Discharges we have recorded
119 discharge periods since 31 May 2025. 115 of them come from Scottish Water's own event-duration-monitoring records (published by the company, May 2025 – Dec 2025); the live feed adds anything after that. The official annual count is the figure to quote.
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Wed 30 Sep 2026, 07:1515 min
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Sun 27 Sep 2026, 12:551 h 5 min
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Wed 23 Sep 2026, 06:305 min
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Wed 23 Sep 2026, 05:2545 min
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Mon 22 Dec 2025, 04:154 h 25 min
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Fri 19 Dec 2025, 07:2055 min
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Thu 18 Dec 2025, 19:153 h 45 min
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Thu 18 Dec 2025, 01:151 h 30 min
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Wed 17 Dec 2025, 18:051 h 55 min
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Wed 17 Dec 2025, 15:151 h 50 min
Show 30 earlier (of 119)
| Started (UK time) | Ended | Discharge time |
|---|---|---|
| 17 Dec 2025, 11:50 | 13:30 | 1 h 40 min |
| 17 Dec 2025, 09:35 | 10:05 | 30 min |
| 17 Dec 2025, 05:15 | 06:25 | 1 h 10 min |
| 14 Dec 2025, 00:15 | 02:30 | 1 d 2 h |
| 13 Dec 2025, 18:25 | 19:35 | 1 h 10 min |
| 13 Dec 2025, 15:20 | 17:10 | 1 h 50 min |
| 11 Dec 2025, 23:20 | 03:30 | 4 h 0 min |
| 10 Dec 2025, 12:40 | 23:05 | 10 h 10 min |
| 10 Dec 2025, 11:50 | 12:15 | 25 min |
| 10 Dec 2025, 09:55 | 11:20 | 1 h 25 min |
| 10 Dec 2025, 08:05 | 09:00 | 55 min |
| 9 Dec 2025, 05:20 | 00:15 | 18 h 55 min |
| 8 Dec 2025, 13:00 | 14:15 | 1 h 15 min |
| 8 Dec 2025, 12:15 | 12:20 | 5 min |
| 8 Dec 2025, 05:45 | 11:30 | 5 h 40 min |
| 7 Dec 2025, 14:55 | 05:10 | 14 h 0 min |
| 6 Dec 2025, 05:35 | 06:05 | 30 min |
| 3 Dec 2025, 10:25 | 11:30 | 1 h 5 min |
| 1 Dec 2025, 17:40 | 09:05 | 15 h 15 min |
| 1 Dec 2025, 08:30 | 09:00 | 30 min |
| 1 Dec 2025, 04:15 | 07:05 | 2 h 50 min |
| 30 Nov 2025, 22:15 | 22:30 | 15 min |
| 29 Nov 2025, 03:50 | 04:25 | 35 min |
| 29 Nov 2025, 01:05 | 03:00 | 1 h 55 min |
| 27 Nov 2025, 14:20 | 15:10 | 50 min |
| 27 Nov 2025, 09:00 | 10:25 | 1 h 25 min |
| 27 Nov 2025, 07:20 | 08:30 | 1 h 10 min |
| 27 Nov 2025, 02:50 | 03:35 | 40 min |
| 26 Nov 2025, 21:15 | 02:30 | 5 h 15 min |
| 26 Nov 2025, 16:30 | 17:00 | 30 min |
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 191 raw blocks were merged into 119 continuous discharge periods (gaps under 15 min joined).
Rain nearby last 30 days
Nearest live rain gauge: Whitburn, 4.1 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
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: © Scottish Water, near-real-time Overflow Map data, open licence for reuse. EDM monitors indicate overflows; they do not confirm them, and this is not advice on water quality. Spill-event history and annual figures: Scottish Water overflow event data, Open Government Licence. Times are shown in UK local time. FloodRadar republishes the monitor's status; it does not measure discharges itself.