Sewage Map

MERSEY - Transitional sewage map and spill data

78 storm overflows listed in the 2025 annual return name this water. 2 companies operate them. Check the latest company report for each outlet below.

78
Outlet records
2,312
Spills in 2025
11,628
Recorded hours
69
Linked to a live feed

3 records show monitor operation below 90%. Annual figures describe the whole of 2025, not today.

Water companies on this water

Official waterbody record ↗How spills are countedSearch the national map

Outlets on MERSEY - Transitional

Filter by the latest company report. The map follows the filters.

Filters apply to the map and list. Recent stops need a current report and a recorded stop time. They do not show whether water is safe.

Showing 10 of 78 outlets

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  • Alexander Drive CSO

    United Utilities · Stewards Brook

    Current status unknown
    2025 annual record:60spills160.6hours
  • Bankhall CSO

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:6spills1.3hours
  • Bankhall Relief CSO

    United Utilities · River Mersey Estuary

    Current status unknown
    2025 annual record:7spills10.3hours
  • Battery Lane CSO

    United Utilities · The Mersey Estuary

    Current status unknown
    2025 annual record:2spills0.3hours
  • Beacons Gutter CSO

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:10spills4.3hours
  • BIRKENHEAD WwTW

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:105spills1,272.5hours
  • Bootle Northern OPC Combined Sewer Overflow

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:9spills3hours
  • Bromborough Pool Village PS

    United Utilities · River Mersey Estuary

    Current status unknown
    2025 annual record:1spill1.6hours
  • BROMBOROUGH WwTW

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:122spills1,426.4hours
  • BROMBOROUGH WwTW

    United Utilities · Mersey Estuary

    Current status unknown
    2025 annual record:94spills665.7hours

Most recorded spills in 2025

The highest 2025 counts among these outlets. A count is events, not volume or harm. Equal counts share a rank.

  1. 1
    Wallasey PS

    United Utilities

    164spills
  2. 2
    BROMBOROUGH WwTW

    United Utilities

    122spills
  3. 3
    LIVERPOOL WwTW

    United Utilities

    118spills
  4. 4
    BIRKENHEAD WwTW

    United Utilities

    105spills
  5. 5
    BROMBOROUGH WwTW

    United Utilities

    94spills

Spills over time

The median outlet on MERSEY - Transitional recorded 15 spills in 2025, against 11 across England.

67 outlets have a comparable count for both 2024 and 2025, with the monitor working at least 90% of each year. 3 recorded more spills, 61 fewer and 3 the same. Together they went from 3,201 to 2,009 spills, a fall of 37%.

Largest rises from 2024 to 2025

YearOutlets with a countTotal spillsMedian per outletEngland median
2025782,3121511
2024753,5553219
2023112712720
20221545413
20211818119

Earlier returns list fewer of these outlets, so totals are not comparable between years. The median per outlet and the like-for-like change are fairer comparisons. Counts are events, not volume.

All outlet records on MERSEY - Transitional

78 outlet records in alphabetical order. Each link opens the outlet page with its latest report and annual history.

A1 outlet
B9 outlets
C3 outlets
D6 outlets
E3 outlets
F2 outlets
G5 outlets
H8 outlets
I1 outlet
J1 outlet
L2 outlets
M5 outlets
N5 outlets
P2 outlets
R1 outlet
S8 outlets
T6 outlets
W10 outlets

Sources and dates

Outlet locations, waterbody links and spill figures come from the Environment Agency 2025 event duration monitoring annual return. The latest company reports come from each operator’s live feed and carry their own dates. Waterbody ID: GB531206908100. The official waterbody record is a source lookup; its classification is not imported here.

All sourcesHow the data worksReport pollution

Questions about MERSEY - Transitional

Which outlets are linked to MERSEY - Transitional?
The source links 78 outlet records to waterbody GB531206908100. The link comes from the annual return; it does not model where a discharge travelled.
How many spills were recorded for MERSEY - Transitional?
78 records report 2,312 spills in 2025 and 11,628 recorded hours. All listed records have a usable count. Outlets can discharge at the same time, so the hours are not the time the whole water was affected.
Who is responsible for the outlets on MERSEY - Transitional?
2 companies operate listed outlets: United Utilities, Dŵr Cymru Welsh Water. Each outlet page names its operator and permit reference.
Which outlets on MERSEY - Transitional are linked to a live feed?
69 of the 78 records are matched to a monitor in a company live feed. A link does not mean the monitor is working now. Use the status filters above to see the latest report for each outlet, with its date. The rest show annual figures only.
How complete is the monitoring for MERSEY - Transitional?
3 of the listed records have monitor operation below 90% for 2025. Events can be missed when a monitor is not working, so low counts from those outlets may understate activity.
Does this show if MERSEY - Transitional is safe?
No. Event duration data does not measure bacteria, chemicals or current water quality. Use official local water-quality advice for that question.