West Mersea Water Recycling Centre

Storm overflow run by Anglian Water, discharging into The Blackwater Estuary.

Storm tank at sewage treatment works Bathing water

Linked bathing water: West Mersea, classified Good for 2025. Named in the company’s return to the Environment Agency. A name opens that bathing water’s official profile, with any pollution warning in the season. The classification is the Environment Agency’s for that bathing season, from all its samples there: it is not a reading of the water today, and it does not say what part this overflow played.

Right now
Monitor offline
The company reports this overflow’s monitor as offline, so it cannot say whether it is discharging.
Times are UK time. Company feed updated 1 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
29spills
0.6 h discharging on 29 days · counted by us, not yet official
2025 official
6spills
8.6 h · −79% on 2024
Rank in Anglian Water
#662
of 1,428 overflows by 2025 spills (1 = most)
Monitor in 2025
100% working
Long-term average 19.0 spills a year

Year by year

The Environment Agency's official annual returns, counted the EA's way (12/24-hour spills). 2026 is our own running count, the same way, from Anglian Water's monitor log and the live feed. The official figure is published next spring.

2021
37 spills · 201 hmonitor 96.9%
2022
13 spills · 2.1 hmonitor 66.6%
2023
34 spills · 12 hmonitor 100%
2024
29 spills · 95 hmonitor 100%
2025
6 spills · 8.6 hmonitor 100%
2026so far
29 spills · 0.6 h

A spill is the EA's 12/24-hour count: the first 12 hours of a discharge count as one, each further 24 hours with discharge as one more. "Monitor" is the share of that year the monitor was working, so a 0 beside a working monitor is a real zero; "no data" means the monitor produced no usable data that year — not zero. Years before 2024 are matched to this site by name and location, because the EA's site IDs changed that year; a monitor figure beside one of them means the outlet's permit confirms the match.

What the 2025 return says

From Anglian Water's annual return to the Environment Agency for this overflow.

High-spill review
High spill threshold not met
Long-term review
Not Applicable - Ongoing investigation
Investigation
Bathing Water and/or Shellfish Water investigation ongoing
Improvement work
No improvement action in reporting period
Monitored since
2019
Water body
Blackwater Outer

"High spill threshold not met" means this overflow did not spill often enough to trigger the EA's formal high-spill review for that year. It is not a statement that the spills were harmless.

Discharges we have recorded

128 discharge periods since 1 Jan 2024. 126 of them come from Anglian Water's own event-duration-monitoring records (published on Stream, Jan 2024 – Mar 2026); the live feed adds anything after that. The official annual count is the figure to quote.

Show 30 earlier (of 128)
StartedEndedDischarge time
0 min
1 min
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2 min
1 min
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1 min
0 min
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0 min
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0 min
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1 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 186 raw blocks were merged into 128 continuous discharge periods (gaps under 15 min joined).

What the feed showed

FloodRadar's own record of every change of state Anglian Water's live feed has shown for this overflow, kept since : 1 state. The feed publishes its status now and its latest discharge, nothing older; the discharges above are read from this. It is here so the figures can be checked.

Show the last 1 states
SeenStatusSinceLatest discharge
Monitor offline →

Rain nearby last 30 days

Nearest live rain gauge: Rainfall gauge nr Colchester, 2.9 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
Colne Barrier (Essex Coast) · 9.2 km
Nearest rain gauge
Site reference
AWS01474 · permit ASETS1320
Coordinates
51.77070, 0.94100

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: © Anglian Water storm overflow activity data, licensed under CC BY 4.0. Annual spill figures: Environment Agency Event Duration Monitoring return, © Environment Agency copyright and/or database right, Open Government Licence (OGL) v3.0. Storm-overflow spill events: © the respective water company, published on Stream (data.streamwaterdata.co.uk) under CC BY 4.0. Discharges marked "EA start/stop data": Environment Agency Event Duration Monitoring storm overflow start/stop detailed data, © Environment Agency copyright and/or database right 2026, Open Government Licence v3.0; the companies' monitor records as the EA received them, not verified by the EA. Discharges marked "via Top of the Poops", come from Top of the Poops' record of the same company feed, used under CC BY-SA 4.0: the feed's own start and end times as its pages print them, not their derived hours. Times are shown in UK local time. FloodRadar republishes the monitor's status and the EA's figures; it does not measure discharges itself.