MCBA Water Treatment Knowledge Hub

Storm overflow register · 2025 annual return

United Utilities storm overflows, 2025

United Utilities reported 2,270 storm overflows in England for 2025. Together they recorded 60,843 spills over 327,452 hours, an average of 26.8 spills per overflow against 20.4 across England. That ranks 9 of 10 companies, where 1 is the fewest spills per overflow. Counting the same overflows in both years, spills were down 23% on 2024.

295 overflows did not spill · 313 spilled more than 60 times · 2,076 had monitors working for 90% of the year or more · 289 sewage treatment works with overflows

Hours spilling by month, 2025

025k50k75k100kJan 2025: 69,814 hours spillingJanFeb 2025: 7,561 hours spillingFebMar 2025: 1,763 hours spillingMarApr 2025: 484 hours spillingAprMay 2025: 4,089 hours spillingMayJun 2025: 13,148 hours spillingJunJul 2025: 6,622 hours spillingJulAug 2025: 2,053 hours spillingAugSep 2025: 41,625 hours spillingSepOct 2025: 22,376 hours spillingOctNov 2025: 71,264 hours spillingNovDec 2025: 86,587 hours spillingDec
Hours spilling, all United Utilities overflows, from the start/stop records. Spills running across a month end are split between the months.

All United Utilities storm overflows

Sorted by hours spilling. Open an overflow for its permit, location, reasons for high spills and improvement status.

OverflowDischarges toSpills 2025Hours 2025Spills vs 2024Monitor uptime
O/S 57 Woodhouse Lane CSO
Overflow on sewer network
EA ID / permit
UUP01424 · 01STA0016
Outlet location
SJ8877059030 (OS grid reference) · View on Apple Maps
WFD catchment
Biddulph Brook (GB112068055360)
2024 spills / hours
31 / 87
Long-term average
30.4 spills a year (monitored since 2021)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 45 hours spilling →
 Trib of Biddulph Brook 27 45 down 13% 100%
Southwaite PS
Storm discharge at pumping station
Company site name
Southwaite PS
EA ID / permit
UUP01794 · 017680340
Outlet location
NY4499045170 (OS grid reference) · View on Apple Maps
WFD catchment
Petteril d/s Blackrack Beck (GB102076074030)
2024 spills / hours
20 / 110
Long-term average
12.5 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 45 hours spilling →
 Trib River Petteril 12 45 down 40% 100%
Commercial Brow CSO
Overflow on sewer network
EA ID / permit
UUP00525 · 01TAM0081
Outlet location
SJ9554095390 (OS grid reference) · View on Apple Maps
WFD catchment
Wilson Brook (GB112069061280)
2024 spills / hours
4 / 4.4
Long-term average
24.0 spills a year (monitored since 2024)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 45 hours spilling →
 Wilson Brook 44 45 up 1000% 99%
Newhall Pumping Station
Storm discharge at pumping station
Company site name
Newhall PS
EA ID / permit
UUP02110 · 016810293
Outlet location
SJ6093745537 (OS grid reference) · View on Apple Maps
WFD catchment
Sales Brook (GB112068055210)
2024 spills / hours
34 / 71
Long-term average
16.7 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 45 hours spilling →
 Sales Brook 14 45 down 59% 100%
Clowes St/Daniel Adamson Road CSO
Overflow on sewer network
Company site name
Clowes Street/Daniel Adamson Road CSO
EA ID / permit
UUP00516 · 016993658
Outlet location
SJ7924097980 (OS grid reference) · View on Apple Maps
WFD catchment
Irwell / Manchester Ship Canal (Irk to confluence with Upper Mersey) (GB112069061452)
2024 spills / hours
47 / 55
Long-term average
60.8 spills a year (monitored since 2019)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 45 hours spilling →
 Manchester Ship Canal 37 45 down 21% 99%
Winston Drive Hensingham CSO 02632
Overflow on sewer network
Company site name
Winston Drive CSO
EA ID / permit
UUP02150 · 017480428
Outlet location
NX9864016940 (OS grid reference) · View on Apple Maps
WFD catchment
Solway Outer South (GB641211630003)
2024 spills / hours
30 / 62
Long-term average
33.9 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Snebra Beck 30 44 no change 100%
Gathurst Lane Shevington CSO
Overflow on sewer network
Company site name
Gathurst Lane (Shevington) CSO
EA ID / permit
UUP00782 · 017091492
Outlet location
SD5400707365 (OS grid reference) · View on Apple Maps
WFD catchment
Douglas - Lower (GB112070064820)
2024 spills / hours
46 / 64
Long-term average
57.7 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 River Douglas 29 44 down 37% 91%
Berrys Lane Combined Sewer Overflow
Overflow on sewer network
Company site name
Berrys Lane
EA ID / permit
UUP00224 · 016982532
Outlet location
SJ5347094380 (OS grid reference) · View on Apple Maps
WFD catchment
Sutton Brook (GB112069061170)
2024 spills / hours
13 / 41
Long-term average
14.0 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Sutton Brook via SWS 11 44 down 15% 97%
Tbc
Overflow on sewer network
Company site name
Woodside House CSO (169KP)
EA ID / permit
UUP02254 · Permit applied for
Outlet location
SJ7255256543 (OS grid reference) · View on Apple Maps
WFD catchment
Fowle Brook (GB112068055400)
2024 spills / hours
26 / 109
Long-term average
21.5 spills a year (monitored since 2024)
Monitor below 90%
Sensor failure / issue · Resolved - January after reporting year
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Fowle Brook 17 44 down 35% 81%
Whitley Drive CSO
Overflow on sewer network
Company site name
Whiteley Drive CSO
EA ID / permit
UUP02119 · 016993576
Outlet location
SD8807005120 (OS grid reference) · View on Apple Maps
WFD catchment
Wince Brook (GB112069061120)
2024 spills / hours
43 / 58
Long-term average
49.2 spills a year (monitored since 2020)
Monitor below 90%
Sensor failure / issue · Resolved - Dec
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Wince Brook 25 44 down 42% 86%
Stockport Road CSO
Overflow on sewer network
Company site name
Stockport Road CSO
EA ID / permit
UUP01863 · 01TAM0086
Outlet location
SD9705002570 (OS grid reference) · View on Apple Maps
WFD catchment
Tame (Chew Brook to Swineshaw Brook) (GB112069061111)
2024 spills / hours
2 / 1.8
Long-term average
3.0 spills a year (monitored since 2024)
Monitor below 90%
Sensor failure / issue · Resolved - Nov
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 County Brook 4 44 up 100% 86%
Hale Road / Dinner Lane CSO
Overflow on sewer network
Company site name
Hale Road/Dinner Lane
EA ID / permit
UUP00875 · 016982704
Outlet location
SJ4633082310 (OS grid reference) · View on Apple Maps
WFD catchment
MERSEY - Transitional (GB531206908100)
2024 spills / hours
21 / 99
Long-term average
14.5 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Lady Pool 12 44 down 43% 100%
Soutergate Village Pumping Station
Storm discharge at pumping station
Company site name
Soutergate Village Pumping Station (Site ID SOUPS) (LAK0094)
EA ID / permit
UUP01779 · 017480359
Outlet location
SD2205081371 (OS grid reference) · View on Apple Maps
WFD catchment
DUDDON (GB531207411800)
Bathing water
Haverigg; Walney Biggar Bank; Walney West Shore; Walney Sandy Gap
Shellfish water
Duddon; Walney
2024 spills / hours
25 / 151
Long-term average
12.9 spills a year (monitored since 2017)
High-spill reason (company)
Data collection - Confirmed exceptional weather
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Soutergate Beck 38 44 up 52% 100%
Dickens Street CSO
Overflow on sewer network
Company site name
Dickens Street CSO
EA ID / permit
UUP00640 · NPSWQD010683
Outlet location
SD6887027442 (OS grid reference) · View on Apple Maps
WFD catchment
Blakewater (GB112071065310)
2024 spills / hours
26 / 63
Long-term average
38.5 spills a year (monitored since 2020)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Queens Park Culvert 18 44 down 31% 100%
Grange Farm Combined Sewer Overflow
Overflow on sewer network
Company site name
Grange Farm CSO
EA ID / permit
UUP00824 · 017580318
Outlet location
NY1096041640 (OS grid reference) · View on Apple Maps
WFD catchment
Crookhurst Beck (GB112075073660)
Bathing water
Allonby
2024 spills / hours
23 / 25
Long-term average
24.3 spills a year (monitored since 2017)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Tributary of Patten Beck 35 44 up 52% 100%
Morecambe Bank CSO
Overflow on sewer network
Company site name
Morecambe Bank CSO
EA ID / permit
UUP01339 · 01LAK0071
Outlet location
SD4087077860 (OS grid reference) · View on Apple Maps
WFD catchment
KENT - transitional (GB531207312000)
2024 spills / hours
36 / 60
Long-term average
29.3 spills a year (monitored since 2019)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Kent Channel 38 44 up 6% 100%
Ashgrove/Southfield Dr CSO
Overflow on sewer network
Company site name
Ash Grove/Southfield Drive CSO
EA ID / permit
UUP00144 · 016982976
Outlet location
SD6454004230 (OS grid reference) · View on Apple Maps
WFD catchment
Westleigh Brook (GB112069060820)
2024 spills / hours
27 / 48
Long-term average
35.0 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 44 hours spilling →
 Culverted Trib Cunningham Brk 21 44 down 22% 100%
Sharoe Green Lane CSO 33034
Overflow on sewer network
Company site name
Sharoe Green Lane combined sewer overflow (33034) (PRE0124)
EA ID / permit
UUP01744 · EPRLP3329XW
Outlet location
SD5393032010 (OS grid reference) · View on Apple Maps
WFD catchment
Savick Brook (GB112071065470)
2024 spills / hours
2 / 0.6
Long-term average
24.3 spills a year (monitored since 2019)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 Savick Brook 23 43 up 1050% 100%
Station Road (Paliham) CSO
Overflow on sewer network
Company site name
Station Road (Padiham) CSO
EA ID / permit
UUP01850 · 01BUR0018
Outlet location
SD7937033870 (OS grid reference) · View on Apple Maps
WFD catchment
Calder - Pendle Water to conf Ribble (GB112071065490)
2024 spills / hours
48 / 39
Long-term average
63.4 spills a year (monitored since 2021)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 River Calder 53 43 up 10% 99%
Coal Pit Lane CSO
Overflow on sewer network
Company site name
Coal Pit Lane CSO
EA ID / permit
UUP00275 · 016950431
Outlet location
SD9287101151 (OS grid reference) · View on Apple Maps
WFD catchment
Medlock (Source to Lumb Brook) (GB112069061151)
2024 spills / hours
17 / 29
Long-term average
18.2 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 River Medlock via SWS 15 43 down 12% 100%
Larburnum Park Pumping Station
Storm discharge at pumping station
Company site name
Hope Terrace PS
EA ID / permit
UUP01113 · NPSWQD011002
Outlet location
SD4915069680 (OS grid reference) · View on Apple Maps
WFD catchment
KENT - transitional (GB531207312000)
Bathing water
Morecambe North
Shellfish water
Morecambe Bay East
2024 spills / hours
29 / 41
Long-term average
22.6 spills a year (monitored since 2018)
Investigation
No investigation activity in reporting period
Improvement
Env Act (SODRP) improvement ongoing
Volume & pollution
Estimate from 43 hours spilling →
 Black Dike, a tributary of the Keer Estuary 21 43 down 28% 100%
Roewoods Outfall Sewer
Overflow on sewer network
Company site name
Roewoods Outfall Sewer (27206) (MAC0028)
EA ID / permit
UUP01680 · 01MAC0028
Outlet location
SJ9030075060 (OS grid reference) · View on Apple Maps
WFD catchment
Bollin (Source to Dean) (GB112069061320)
2024 spills / hours
30 / 49
Long-term average
37.4 spills a year (monitored since 2019)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Monitor below 90%
Sensor failure / issue · Resolved - Jul
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 Un-Named Trib of River Bollin 31 43 up 3% 88%
Warrington Road CSO
Overflow on sewer network
EA ID / permit
UUP02025 · 01HAL0054
Outlet location
SJ5205084650 (OS grid reference) · View on Apple Maps
WFD catchment
MERSEY - Transitional (GB531206908100)
2024 spills / hours
26 / 63
Long-term average
32.8 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 Bowers Brook 15 43 down 42% 100%
Kirkland Wastewater Treatment Works
Inlet overflow at sewage works
Sewage works
Kirkland
Company site name
KIRKLAND WwTW
EA ID / permit
UUP01086 · 017470029
Outlet location
NY0733017430 (OS grid reference) · View on Apple Maps
WFD catchment
Ehen (upper including Liza) (GB112074070010)
2024 spills / hours
55 / 51
Long-term average
54.2 spills a year (monitored since 2021)
High-spill reason (company)
Data collection - Confirmed exceptional weather
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 43 hours spilling →
 Hawes Gill 51 43 down 7% 100%
Upton Road CSO 513N8
Overflow on sewer network
Company site name
Upton Road CSO
EA ID / permit
UUP01980 · 01WIR0004
Outlet location
SJ2762089732 (OS grid reference) · View on Apple Maps
WFD catchment
The Birket including Arrowe Brook and Fender (GB112068060530)
2024 spills / hours
38 / 280
Long-term average
32.1 spills a year (monitored since 2018)
Investigation
Operational investigation completed
Improvement
Operational improvement completed
Volume & pollution
Estimate from 42 hours spilling →
 River Fender 28 42 down 26% 99%
Coalpit Wood CSO
Overflow on sewer network
Company site name
Coal Pitt Wood CSO
EA ID / permit
UUP00517 · 017580316
Outlet location
NY0915033110 (OS grid reference) · View on Apple Maps
WFD catchment
Broughton Beck (GB112075073570)
2024 spills / hours
33 / 70
Long-term average
39.6 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 42 hours spilling →
 Dovenby Beck 22 42 down 33% 100%
Northwich WwTW
Inlet overflow at sewage works
Sewage works
Northwich
Company site name
NORTHWICH WwTW
EA ID / permit
UUP01413 · 016810099
Outlet location
SJ6373074126 (OS grid reference) · View on Apple Maps
WFD catchment
Weaver (Dane to Frodsham) (GB112068060500)
2024 spills / hours
20 / 54
Long-term average
11.4 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 42 hours spilling →
 River Weaver 10 42 down 50% 100%
Bollin Walk CSO 27074
Overflow on sewer network
Company site name
The Wilmslow Park Road CSO
EA ID / permit
UUP00265 · 016993490
Outlet location
SJ8529081230 (OS grid reference) · View on Apple Maps
WFD catchment
Bollin (Source to Dean) (GB112069061320)
2024 spills / hours
20 / 33
Long-term average
26.1 spills a year (monitored since 2019)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 42 hours spilling →
 Whitfield Brook 21 42 up 5% 96%
39 Park Avenue CSO
Overflow on sewer network
Company site name
Park Avenue CSO (to Yarrow)
EA ID / permit
UUP00043 · 017190821
Outlet location
SD5526117906 (OS grid reference) · View on Apple Maps
WFD catchment
Yarrow DS Big Lodge Water (GB112070064952)
2024 spills / hours
33 / 74
Long-term average
39.4 spills a year (monitored since 2019)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 42 hours spilling →
 River Yarrow 25 42 down 24% 100%
Mere Drive / Rake Lane CSO (374Y5)
Overflow on sewer network
Company site name
Mere Drive/Rake Lane CSO
EA ID / permit
UUP01286 · 016993604
Outlet location
SD7916001880 (OS grid reference) · View on Apple Maps
WFD catchment
Irwell (Croal to Irk) (GB112069061451)
2024 spills / hours
18 / 33
Long-term average
40.2 spills a year (monitored since 2021)
Investigation
Operational investigation completed
Improvement
Operational improvement completed
Volume & pollution
Estimate from 41 hours spilling →
 Slack Brook 14 41 down 22% 100%
Cranberry Lodge Pumping Station
Storm discharge at pumping station
Company site name
Cranberry Lodge Pumping Station (Site ID 50003) (WIG0162)
EA ID / permit
UUP00559 · 01WIG0162
Outlet location
SD5698001890 (OS grid reference) · View on Apple Maps
WFD catchment
Poolstock Brook (GB112070061610)
2024 spills / hours
3 / 10
Long-term average
5.0 spills a year (monitored since 2019)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 Park Brook 6 41 up 100% 100%
Arkwright Street CSO
Overflow on sewer network
Company site name
Arkwright Street CSO
EA ID / permit
UUP00129 · 016982739
Outlet location
SD9013604917 (OS grid reference) · View on Apple Maps
WFD catchment
Wince Brook (GB112069061120)
2024 spills / hours
29 / 29
Long-term average
42.3 spills a year (monitored since 2020)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 Stock Brook via SWS 41 41 up 41% 100%
The Avenue Syphon CSO 452UO
Overflow on sewer network
Company site name
The Avenue Syphon CSO
EA ID / permit
UUP01909 · 016982888
Outlet location
SJ7645092842 (OS grid reference) · View on Apple Maps
WFD catchment
Mersey (upstream of Manchester Ship Canal) (GB112069061030)
2024 spills / hours
26 / 43
Long-term average
43.1 spills a year (monitored since 2019)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 Stromford Brk Trib Rvr Mersey 24 41 down 8% 100%
Outside 91 Styal Road CSO
Overflow on sewer network
Company site name
Outside 91 Styal Road CSO
EA ID / permit
UUP01490 · 01STK0048
Outlet location
SJ8397087670 (OS grid reference) · View on Apple Maps
WFD catchment
Mersey (upstream of Manchester Ship Canal) (GB112069061030)
2024 spills / hours
22 / 76
Long-term average
27.4 spills a year (monitored since 2021)
Investigation
Env Act (SODRP) investigation ongoing, Operational investigation completed
Improvement
Operational improvement completed
Volume & pollution
Estimate from 41 hours spilling →
 Gatley Brook via SWS 7 41 down 68% 99%
Padiham Leisure Centre CSO
Overflow on sewer network
Company site name
Padiham Leisure Centre CSO
EA ID / permit
UUP00083 · 017190925
Outlet location
SD7912033690 (OS grid reference) · View on Apple Maps
WFD catchment
Calder - Pendle Water to conf Ribble (GB112071065490)
2024 spills / hours
25 / 73
Long-term average
35.8 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 River Calder 25 41 no change 99%
Danefield Road CSO 45052
Overflow on sewer network
Company site name
The Danefield Road CSO
EA ID / permit
UUP00608 · 016982773
Outlet location
SJ7928093210 (OS grid reference) · View on Apple Maps
WFD catchment
Mersey (upstream of Manchester Ship Canal) (GB112069061030)
2024 spills / hours
13 / 28
Long-term average
16.6 spills a year (monitored since 2018)
Investigation
Env Act (SODRP) investigation ongoing
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 River Mersey (Under M63) 16 41 up 23% 100%
Primrose Lane CSO
Overflow on sewer network
Company site name
Primrose Lane CSO
EA ID / permit
UUP01580 · 016892340
Outlet location
SK0232094110 (OS grid reference) · View on Apple Maps
WFD catchment
Long Clough Brook (GB112069060700)
2024 spills / hours
41 / 66
Long-term average
52.2 spills a year (monitored since 2021)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
Env Act (SODRP) improvement ongoing
Volume & pollution
Estimate from 41 hours spilling →
 Long Clough Brook 31 41 down 24% 99%
Elton PS
Storm discharge at pumping station
Company site name
Elton PS
EA ID / permit
UUP00703 · 01CHE0025
Outlet location
SJ4646075690 (OS grid reference) · View on Apple Maps
WFD catchment
Peckmill Brook, Hoolpool Gutter at Ince Marshes. (GB112068060330)
2024 spills / hours
16 / 48
Long-term average
13.5 spills a year (monitored since 2024)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 West Central Drain, Mersey Est 11 41 down 31% 97%
Lever Street No 3 CSO
Overflow on sewer network
Company site name
Lever Street Number 3 CSO
EA ID / permit
UUP01134 · 016983263
Outlet location
SD7196007830 (OS grid reference) · View on Apple Maps
WFD catchment
Middle Brook (GB112069064540)
2024 spills / hours
3 / 1.1
Long-term average
33.6 spills a year (monitored since 2019)
High-spill reason (company)
Not asset maintenance - Hydraulic capacity
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 41 hours spilling →
 Jenny Beck 39 41 up 1200% 100%
Knutsford Main Pumping Station
Storm discharge at pumping station
Company site name
Knutsford Main PS
EA ID / permit
UUP01092 · 01MAC0144
Outlet location
SJ7548078730 (OS grid reference) · View on Apple Maps
WFD catchment
Birkin Brook - Source to Mobberley Brook (GB112069061340)
2024 spills / hours
7 / 22
Long-term average
9.9 spills a year (monitored since 2018)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 Moor Pool 9 40 up 29% 100%
56 Cross Lane CSO (STK0152)
Overflow on sewer network
Company site name
56 Cross Lane combined sewer overflow (STK0152)
EA ID / permit
UUP02257 · EPRJB3891RX
Outlet location
SJ9520088492 (OS grid reference) · View on Apple Maps
WFD catchment
Goyt (Etherow to Mersey) (GB112069061000)
2024 spills / hours
2 / 1.1
Long-term average
2.0 spills a year (monitored since 2024)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 Un-named tributary of Marple Brook 2 40 no change 95%
Grisedale Close CSO
Overflow on sewer network
Company site name
Grisedale Close CSO
EA ID / permit
UUP00868 · 017480430
Outlet location
NX9808015940 (OS grid reference) · View on Apple Maps
WFD catchment
Solway Outer South (GB641211630003)
Bathing water
St Bees
2024 spills / hours
23 / 14
Long-term average
21.0 spills a year (monitored since 2018)
Monitor below 90%
Sensor failure / issue · Resolved - Sep
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 Pow Beck 18 40 down 22% 86%
Warrington North WwTW
Inlet overflow at sewage works
Sewage works
Warrington North
Company site name
WARRINGTON NORTH WwTW
EA ID / permit
UUP02023 · 016983122
Outlet location
SJ5804086890 (OS grid reference) · View on Apple Maps
WFD catchment
MERSEY - Transitional (GB531206908100)
2024 spills / hours
13 / 40
Long-term average
44.7 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 Mersey Estuary 9 40 down 31% 100%
92 Burnley Road CSO 081HP
Overflow on sewer network
Company site name
92 Burnley Road CSO
EA ID / permit
UUP00063 · 01BUR0010
Outlet location
SD8225028070 (OS grid reference) · View on Apple Maps
WFD catchment
Limy Water (GB112069064680)
2024 spills / hours
18 / 44
Long-term average
31.3 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 Limy Water 16 40 down 11% 100%
Fairfield Street CSO
Overflow on sewer network
Company site name
Fairfield Street CSO
EA ID / permit
UUP00717 · 016982730
Outlet location
SJ8543097630 (OS grid reference) · View on Apple Maps
WFD catchment
Medlock (Lumb Brook to Irwell) (GB112069061152)
2024 spills / hours
27 / 45
Long-term average
22.0 spills a year (monitored since 2020)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 40 hours spilling →
 River Medlock 26 40 down 4% 100%
Goyt Side Pumping Station
Storm discharge at pumping station
Company site name
Goyt Side PS
EA ID / permit
UUP00822 · 016982416
Outlet location
SK0015085100 (OS grid reference) · View on Apple Maps
WFD catchment
Goyt (Randall Carr Brook to Sett). (GB112069060880)
2024 spills / hours
14 / 12
Long-term average
24.0 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 39 hours spilling →
 River Goyt 27 39 up 93% 100%
Bankhall Relief CSO 99006
Overflow on sewer network
Company site name
Northern CSO
EA ID / permit
UUP00184 · 016830968
Outlet location
SJ3300093900 (OS grid reference) · View on Apple Maps
WFD catchment
MERSEY - Transitional (GB531206908100)
Bathing water
Wallasey
Shellfish water
North Wirral (East)
2024 spills / hours
37 / 54
Long-term average
38.5 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 39 hours spilling →
 The Mersey Estuary 20 39 down 46% 100%
4 Tavlin Avenue CSO
Overflow on sewer network
Company site name
4 Tavlin Avenue CSO
EA ID / permit
UUP00045 · 016993627
Outlet location
SJ5992089940 (OS grid reference) · View on Apple Maps
WFD catchment
Sankey Brook (Rainford Brook to Mersey) (GB112069061200)
2024 spills / hours
5 / 30
Long-term average
4.2 spills a year (monitored since 2021)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 39 hours spilling →
 Dallam Brook via SWS 6 39 up 20% 99%
Oxcliffe Rd PS No 1 & EO to Overton
Storm discharge at pumping station
Company site name
Oxcliffe Road Pumping Station (Site ID 25006) (LAN0028)
EA ID / permit
UUP01496 · 017290613
Outlet location
SD4476061080 (OS grid reference) · View on Apple Maps
WFD catchment
LUNE (GB531207212100)
Bathing water
Morecambe South
2024 spills / hours
26 / 22
Long-term average
15.5 spills a year (monitored since 2017)
Investigation
No investigation activity in reporting period
Improvement
Env Act (SODRP) improvement ongoing
Volume & pollution
Estimate from 39 hours spilling →
 The River Lune Estuary 25 39 down 4% 100%
St Andrews Rd Brooks Av CSO 09001
Overflow on sewer network
Company site name
Junction of St Andrews Road/Brooks Avenue CSO
EA ID / permit
UUP01810 · 016993585
Outlet location
SD7786008710 (OS grid reference) · View on Apple Maps
WFD catchment
Irwell (Roch to Croal) (GB112069060840)
2024 spills / hours
12 / 33
Long-term average
12.3 spills a year (monitored since 2019)
Investigation
No investigation activity in reporting period
Improvement
No improvement action in reporting period
Volume & pollution
Estimate from 39 hours spilling →
 Black Lane Brook 10 39 down 17% 100%

Sewage treatment works

Storm tanks and inlet overflows at each United Utilities sewage works. The figures are 2025 spills.

← All water companies · Contains Environment Agency data licensed under the Open Government Licence v3.0. How to read the data.