Coylton WwTW (Inlet) CSO

Storm overflow run by Scottish Water, discharging into Byres Burn.

CSO
Right now
Not discharging
Last discharge ended on (5 days ago).
Times are UK time. Company feed updated 10 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
4overflow events
1.4 h discharging on 4 days · live feed since 23 Sep, not yet official
2025 official
12overflow events
7.9 h · −54% on 2024
Rank in Scottish Water
—
No ranking for this overflow.
Monitor in 2025
75.6% working
Share of the year the monitor reported

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 23 September (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
14 events · 35 hmonitor 100%
2023
20 events · 43 hmonitor 95.9%
2024
26 events · 36 hmonitor 87.4%
2025
12 events · 7.9 hmonitor 75.6%
2026since 23 Sep
4 events · 1.4 h

"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 Byres Burn. They share the sewer and the storm, so one outlet's figures are only part of what reaches the water.

40m Coylton WwTW CSO (Screened)CSO003113 —no 2025 figure

This overflow: 12 spills in 2025. Distances are between the published outlet points.

Downstream of this overflow

The next gauge downstream that the river map places is Mainholm (Ayr), 11.2 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. This overflow was placed on the river by its position alone. 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

17 discharge periods since 4 Jan 2025. 12 of them come from Scottish Water's own event-duration-monitoring records (published by the company, Jan 2025 – Oct 2025); the live feed adds anything after that. The official annual count is the figure to quote.

Show 7 earlier
StartedEndedDischarge time
20 min
16 min
24 min
55 min
47 min
36 min
1 h 5 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 20 raw blocks were merged into 17 continuous discharge periods (gaps under 15 min joined).

Rain nearby last 30 days

Nearest live rain gauge: Bow Burn Raingauge, 2.1 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

Nearest river gauge
Mainholm (Ayr) · 4.2 km
Nearest rain gauge
Site reference
CSO007441
Coordinates
55.44767, -4.52966

Tell me when this overflow discharges

One message when the company's monitor reports a new discharge here. At most one every 6 hours.

Setting this alert needs JavaScript. The alerts you already have are on your alerts page.

The alert repeats the monitor's status: whether the overflow is discharging, not how much or why. It can only tell you about a discharge that starts after you turn it on.

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.