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Southampton Test - 2025 Sewage

Polluted by sewage 1,148 hours in 2025

© OpenStreetMap contributors
Contains OS Data © Crown copyright & database right 2021-2024
© Top of the Poops 2021-2024

Which Year?

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✔ means we have live data (𝑥 if not)

View Annual Sewage Data

You're looking at the totals that we have calculated for sewage in Southampton Test for 2025. It is an estimate, based on very poor quality live data from the Water Companies. This may not align with the 'official' reported sewage values from the water companies, which is reported in April following then end of the year - so 2025 numbers are reported in April 2026.

What's a potential overflow? If the CSO goes 'Offline' while its Overflowing, we don't know if it stopped overflowing until we get a 'Stop' event.

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Daily Data

Jan - 433 hours
Feb - 266 hours
Mar - 0 hours
Apr - 0 hours
May - 0 hours
Jun - 7 hours
Jul - 0 hours
Aug - 52 hours
Sept - 38 hours
Oct - 94 hours , 1 potential
Nov - 17 hours
Dec - 238 hours
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Totals so far

Company Site Name Receiving Waterway Overflow Days Total Duration (hours) Offline/Potential Pollution
Southern Water MILLBROOK SSO - 115420 River Test 24 399h 7m -
Southern Water PORTSWOOD SSO - 115428 River Itchen Estuary 31 377h 13m -
Southern Water PORTSWOOD SSO - 115428 River Itchen Estuary 10 147h 45m -
Southern Water LAWN ROAD SOUTHAMPTON CSO - 108450 Itchen Estuary 13 89h 15m 1 h
Southern Water MILLBROOK SSO - 115420 River Test 6 83h 45m -
Southern Water PARK ROAD SOUTHAMPTON CSO - 108467 Test Estuary 8 23h 45m -
Southern Water MILLBROOK CSO - 116169 River Test 6 15h 7m -
Southern Water MILLBROOK CSO - 116169 River Test 1 4h 58m -
Southern Water IMPERIAL ROAD MOUNT PLEASANT CEO - 111369 River Itchen 5 3h 32m -
Southern Water SIRDAR ROAD SOUTHAMPTON CSO - 108794 River Itchen 3 1h 50m -
Southern Water IMPERIAL ROAD MOUNT PLEASANT CEO - 111369 River Itchen 2 1h 32m -
Southern Water LIVERPOOL STREET SOUTHAMPTON CSO - 108482 Itchen Estuary 1 0h 18m -
Southern Water PARK ROAD SOUTHAMPTON CSO - 108467 Test Estuary 0 0h -
Southern Water LIVERPOOL STREET SOUTHAMPTON CSO - 108482 Itchen Estuary 0 0h -
Southern Water UPPER SHAFTSBURY AVENUE SOUTHAMPTON CSO - 108792 River Itchen 0 0h -
Southern Water SIRDAR ROAD SOUTHAMPTON CSO - 108794 River Itchen 0 0h -
Southern Water LAWN ROAD SOUTHAMPTON CSO - 108450 Itchen Estuary 0 0h -

Data Sources & Accuracy

EDM (Event Duration Monitoring) data and Consented Discharges to Controlled Waters with Conditions from Environment Agency & Data Map Wales, and Scottish Water

Experimental derived data from Thames Water API, Some data may be missing or inaccurate. Live sewage data from Stream Water API

Annual figures up to and including 2025 come from official water company returns. The 2026 figure is our own estimate, derived continuously from the companies' live data feeds.

Uses Environment Agency rainfall data from the real-time data API (Beta) - Rainfall data is delayed by up to two days.

This website is intended to provide an accurate representation of the Environment Agency data. The data is hard to use, and thus some errors may have been made. If you find something that is incorrect, please raise an issue at the GitHub issues page and we'll endeavour to fix it quickly.

This project is not associated, approved or endorsed by any of the companies whose logos you see here.