Sewage Map

Thames Water sewage map and spill data

Thames Water operates 581 storm overflows listed in the 2025 England annual return, on 340 named receiving waters. Check the latest company report for each outlet below.

581
Outlet records
9,189
Spills in 2025
107,822
Recorded hours
556
Linked to a live feed

2 records have no usable spill count. 32 records show monitor operation below 90%. Annual figures describe the whole of 2025, not today. Company totals are not a league table.

Waters with the most Thames Water outlets

Receiving waters named in the annual return, with the number of this company’s outlets on each.

Official annual data ↗Thames Water 2025 reportHow spills are countedReport pollution

Thames Water outlets

Filter by the latest company report, or search by outlet, receiving water, town or postcode. 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 581 outlets

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  • (Northern) low level no 1 brook green

    Thames Water · R.THAMES ( Tidal )

    Current status unknown
    2025 annual record:1spill0.4hours
  • 15 coldharbour lane, bushey

    Thames Water · Colne Brook

    Current status unknown
    2025 annual record:0spills0hours
  • Abbess Roding STW

    Thames Water · Coopers Brook

    Current status unknown
    2025 annual record:64spills683hours
  • Abbey Mills A Storm SPS

    Thames Water · R.LEE (Chanelsea River South)

    Current status unknown
    2025 annual record:0spills0hours
  • Abbeydale Road

    Thames Water

    Current status unknown
    2025 annual record:1spill2.6hours
  • Abingdon STW

    Thames Water · Odhay Hill Ditch/RIVER Thames

    Current status unknown
    2025 annual record:13spills112hours
  • Acton Ealing SPS

    Thames Water · Thames ( Tidal )

    Current status unknown
    2025 annual record:1spill11hours
  • Aldermaston STW

    Thames Water · Groundwater via Land Treatment

    Current status unknown
    2025 annual record:31spills247.8hours
  • Aldershot CSO

    Thames Water

    Current status unknown
    2025 annual record:2spills8.3hours
  • Aldershot STW

    Thames Water · Blackwater River

    Current status unknown
    2025 annual record:9spills37.8hours

Most recorded spills in 2025

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

  1. 1
    Markyate STW

    River Ver

    155spills
  2. 2
    Stewkley STW

    Hardwick Brook

    143spills
  3. 3
    South Moreton STW

    Mill Brook

    137spills
  4. 4
    Cirencester STW

    Shorncote Ditch

    125spills
  5. 5
    Winterbourne STW

    Winterbourne Stream

    116spills

Spills over time

The median outlet run by Thames Water recorded 6 spills in 2025, against 11 across England.

518 outlets have a comparable count for both 2024 and 2025, with the monitor working at least 90% of each year. 26 recorded more spills, 435 fewer and 57 the same. Together they went from 21,404 to 8,427 spills, a fall of 61%.

Largest rises from 2024 to 2025

YearOutlets with a countTotal spillsMedian per outletEngland median
20255799,189611
202457522,9032019
202342213,6991620
2022882,33220.513
2021864,12242.519

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 Thames Water outlet records

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

A26 outlets
B54 outlets
C74 outlets
D24 outlets
E24 outlets
F21 outlets
G20 outlets
H42 outlets
I5 outlets
J6 outlets
K17 outlets
L28 outlets
M29 outlets
N18 outlets
O7 outlets
P22 outlets
Q1 outlet
R18 outlets
S61 outlets
T19 outlets
U2 outlets
V1 outlet
W57 outlets
X5 outlets

Sources and dates

Outlet locations, receiving waters and spill figures come from the Environment Agency 2025 event duration monitoring annual return for England. The latest reports come from the Thames Water live feed and carry their own dates.

All sourcesCoverage and gapsHow the data works

Questions about Thames Water

What do the Thames Water figures cover?
This page totals 579 outlet records with a usable 2025 spill count, out of 581 records in the England dataset. Missing values are not counted as zero.
How many Thames Water outlets are linked to a live feed?
556 records are matched to a monitor in the company live feed. A link does not mean the monitor is working now. Use the status filters above to see the latest report and its date. 25 records have annual figures only.
How many Thames Water outlets recorded zero spills in 2025?
135 records report zero counted spills. 32 records have monitor operation below 90%, so a zero from one of those outlets may not cover the whole year.
Does a recorded spill show how much sewage was discharged?
No. Event duration monitors report when an overflow operated. They do not measure the volume released or the water quality.
Can I compare Thames Water with another company?
Take care. 32 records have monitor operation below 90%, and companies differ in outlet numbers and area. Check missing values and monitor coverage before making a comparison.
How do I report pollution from a Thames Water outlet?
Use the official pollution reporting route in our guide. Give the outlet name, permit reference and the time you saw the problem. Sewage Map does not send incident reports.