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Harpenden and Berkhamsted was polluted by sewage 45 times in 2023
lasting 288 hours
- but monitoring was disabled in some locations, so could be more

© OpenStreetMap contributors
Contains OS Data © Crown copyright & database right 2021-2023
© Top of the Poops 2021-2023
✔ means we have experimental daily data since 2023
Totals for Harpenden and Berkhamsted in 2023
5 Sites polluted by Thames Water
45 sewage dumps
288 h duration
That's 12 days. 3.8 times a month, over the year
Change Over Time
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Daily Data Since 2023
     Monitoring Online      Monitoring Offline      Polluting      Potentially Polluting      Unknown
Daily data is experimental and data is not guaranteed to be accurate. Please inform us of any issue, we will fix.

Pollution Summary 2023

Here are all the reported sewage overflow totals for Harpenden and Berkhamsted in 2023. Sometimes sewage can be being dumped for months at a time.

Reporting refers to how much of the time the monitoring was active. In this constituency 1 of the total 7 CSO locations had reporting enabled for less than half the year, of which 1 had zero reporting.

Company Waterway Site Sewage Dumps Duration (Hours) Reporting %
Thames Water Grand Union Canal BERKHAMSTED SEWAGE TREATMENT WORKS 33 227 99.8
Thames Water Lee Harpenden 4 35 99.8
Thames Water Gw Via Boreholes CADDINGTON WWTW 3 14 100
Thames Water River Ver MARKYATE WASTEWATER TREATMENT WORKS 4 10 93.5
Thames Water Into Guc/Reservoir Tring (2m - Main Outfall) 1 1 93.1
Thames Water River Bulborne Trumps Green 0 0 100
Thames Water River Lee WHEATHAMPSTEAD PUMPING STATION , HE 0 0 0

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. This 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.