Wessex Water storm overflows

1,295 storm overflows · 1,254 with a live status feed · regulated by the Environment Agency.

Discharging now
0
of 1,245 overflows reporting live
Spills in 2025
24,175
official, from 1,285 monitored overflows
Hours in 2025
188k
total discharge time, 146 h per overflow
Average per overflow
18.8
spills each in 2025 · -45% on 2024 (33.9)

Discharging now

None reported discharging in the latest feed update. "Not discharging" means the monitors report no discharge — not that the water is clean.

Year by year

Spills reported across all of Wessex Water's monitored overflows.

2021975 sites
21,610 spills · 134k h
20221,117 sites
20,194 spills · 117k h
20231,232 sites
38,504 spills · 341k h
20241,295 sites
43,931 spills · 405k h
20251,285 sites
24,175 spills · 188k h

More overflows were monitored each year (975 in 2021, 1,285 in 2025), so part of any rise is more monitors, not only more spilling.

Official Environment Agency Event Duration Monitoring returns, 12/24-hour counting method (the first 12 hours of a discharge count as one spill, each further 24 hours as one more). Earlier years are matched to today's overflows by name and location, because the EA's site IDs changed between returns; a site that could not be matched is left out of that year rather than guessed.

Most spills in 2025

The overflows that spilled most often. A red tag means discharging right now.

1
1673,119 h
2
1392,529 h
3
Martinstown PS The South Winterbourne
1292,030 h
4
1162,679 h
5
Chicksbridge PS River Bride
1121,957 h
6
Buckland Newton Wrc River Lydden
1081,684 h
7
106730 h
8
East Harptree Wrc Trib Of River Chew
991,283 h
9
Muller Road CSO Horfield Brook
98376 h
10
972,149 h
11
Great Badminton WwTW Luckington Brook
941,904 h
12
9296 h
13
921,540 h
14
851,978 h
15
Chilcompton WwTW Somer Stream
85243 h
16
84242 h
17
831,315 h
18
Iwerne Minster Wrc River Iwerne
831,816 h
19
Portbury Wharf STW Severn Estuary
83721 h
20
Halstock Water Recycling Centre Tributary Of The River Yeo
821,424 h
21
Montacute CSO Tributary Of Wellahms Brook
821,314 h
22
811,551 h
23
811,252 h
24
Filton Avenue CSO Horfield Brook
80194 h
25
Hazelbury Bryan River Lydden
791,569 h

Rivers and seas it discharges into most

Spills in 2025 from Wessex Water's overflows, by receiving water (names grouped approximately).

1
River Avon 213 overflows
3,52414k h
2
River Frome 53 overflows
7764,424 h
3
River Stour 22 overflows
4123,967 h
4
River Yeo 17 overflows
3683,491 h
5
River Bourne 5 overflows
3605,828 h
6
Wellow Brook 16 overflows
2921,196 h
7
River Trym 12 overflows
283311 h
8
Horfield Brook 5 overflows
282855 h
9
River Lydden 4 overflows
2743,873 h
10
Cam Brook 8 overflows
2601,607 h

Concerned about an overflow?

Report pollution you can see to the Environment Agency on 0800 80 70 60 — they log and investigate incidents. Complaints about a company's service go to the company first.

Live status: © Wessex 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. FloodRadar republishes the monitors' status and the published figures; it does not measure discharges itself, and a monitor reports a discharge, not its volume or its cause.