Henley Town Council Water Testing

Henley Town Council is proud to partner with the volunteer group HoTWater, providing live, up-to-date E. coli measurements in the River Thames – right here in Henley-on‑Thames. These real-time results appear on our homepage, giving both locals and visitors vital insights into water quality for swimming, boating, paddleboarding, and more.

A Partnership for Cleaner Water

This initiative is a true community effort—supported by councils, clubs, volunteers, and water users alike. By sharing real-time data, we empower everyone to enjoy the river safely and responsibly.

Henley-on-Thames Water

Poor water quality Henley Bridge 1219

Poor water quality Marsh Lock 1222

Poor water quality River & Rowing Museum 1662

Why this matters

Unlike designated bathing sites, Henley doesn’t receive routine Environment Agency water monitoring. To fill this gap, HoTWater volunteers sample river water at four key locations (Marsh Lock, the River & Rowing Museum, Henley Bridge, and Fawley Meadows) using certified Fluidion analyzers. Samples are taken Tuesdays and Thursdays, with results published the next day

 

Understanding the Results

Results are communicated in colony-forming units (cfu/100 ml) of E. coli, using DEFRA classifications for reference:

  • Excellent (≤ 500 cfu)

  • Sufficient (≤ 900 cfu)

  • Poor (above 900 cfu—entering advised against)

Please note: these classifications are based on single samples and do not include other indicators like Intestinal Enterococci or sediment levels

For more information on the testing go the HoTWater Website

Make Informed Choices – Download the App

Want water-quality updates on the go? Download the HoTWater app (available on iPhone and iPad) to:

  • View the most recent test results instantly

  • Track site-specific trends over time

Head to the App Store via the link on our homepage and stay informed whenever you head to the river!