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Henley and Thame - 2025 Sewage

Polluted by sewage 4,054 hours in 2025 , monitoring offline 2,480 hours

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

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View Annual Sewage Data

You're looking at the totals that we have calculated for sewage in Henley and Thame 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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Constituencies near Henley and Thame

Daily Data

Jan - 1,445 hours
Feb - 1,139 hours
Mar - 204 hours
Apr - 24 hours
May - 0 hours , 236 offline
Jun - 0 hours , 62 offline
Jul - 2 hours , 249 offline
Aug - 15 hours , 1,008 offline
Sept - 66 hours , 224 offline
Oct - 11 hours
Nov - 369 hours , 472 offline
Dec - 774 hours , 227 offline
Daily data is experimental and data is not guaranteed to be accurate. Please inform us of any issue, we will fix.
Please note: We don't have rainfall data for Wales. If you know where to source it please let us know!
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Totals so far

Company Site Name Receiving Waterway Overflow Days Total Duration (hours) Offline/Potential Pollution
Thames Water Little Milton STW Gainsbridge Brook 54 1,165 h 15m -
Thames Water Wheatley STW Wheatley Ditch 53 784 h 45m 213 h
Thames Water Benson STW Howbery Ditch 18 361 h 2m 398 h
Thames Water Wheatley STW Wheatley Ditch 28 326 h -
Thames Water Thame STW Lashlake Stream 22 325 h 30m -
Thames Water Chalgrove STW Warpsgrave Ditch 15 239 h 15m -
Thames Water Little Milton STW Gainsbridge Brook 11 146 h 45m -
Thames Water Chinnor STW Henton Stream 30 142 h 621 h
Thames Water Thame STW Lashlake Stream 10 135 h 30m -
Thames Water Watlington STW Pyrton Stream 28 128 h 15m -
Thames Water Dorchester STW Thame 12 116 h 59m -
Thames Water Friday Street (Henley) SPS Thames 6 44 h 44m 527 h
Thames Water Chalgrove STW Warpsgrave Ditch 6 39 h 30m -
Thames Water Tetsworth STW Latchford Brook 5 34 h 30m -
Thames Water Chinnor STW Henton Stream 6 26 h 10m -
Thames Water Beckley STW Otmoor Lane Ditch 3 19 h -
Thames Water Tetsworth STW Latchford Brook 2 8 h 15m -
Thames Water Beckley STW Otmoor Lane Ditch 1 5 h -
Thames Water Forest Hill STW Polecat End Ditch 2 3 h 30m -
Thames Water Sonning Common STW Into Land 1 1 h 30m -
Thames Water Friday Street (Henley) SPS Thames 1 0 h 56m 171 h
Thames Water Manor Farm Road (Sydenham) SPS Sydenham Stream 0 0 h -
Thames Water Caversham (Reading) SPS Thames 0 0 h -
Thames Water Watlington STW Pyrton Stream 0 0 h -
Thames Water Dorchester STW Thame 0 0 h -
Thames Water Forest Hill STW Polecat End Ditch 0 0 h -
Thames Water Benson STW Howbery Ditch 0 0 h -
Thames Water Caversham (Reading) SPS Thames 0 0 h 548 h
Thames Water Sonning Common STW Into Land 0 0 h -

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

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.

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Analysing sewage pollution by the Water Industry

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© 2020-2025 Top-Of-The-Poops CC-BY-SA 4.0,
© Openstreetmap contributors, Contains OS data © Crown copyright and database right 2021-2025,
Contains Water UK National Storm Overflow Hub Data CC-BY-SA 4.0 and analysis © 2025 Top-Of-The-Poops

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