A Flood Alert was issued for River Thames for Henley, Remenham, Medmenham and its tributaries in Buckinghamshire, Oxfordshire, Windsor and Maidenhead, Wokingham between 25th and 27th February 2026. Affected watercourses included the River Thames, Assendon Stream, Hambledon Brook.
During this event, FloodRadar monitoring gauges recorded notable rises. The River Thames at Sonning Lock rose 3.34m, peaking at 3.50m, while the River Thames at Boulters Lock climbed 3.29m.
Environment Agency advice issued
High river levels today may lead to flooding. Flooding is possible on 27 February 2026. River levels are high but slowly declining on the River Thames. Flooding of low lying land and roads is expected to continue today, 27 February 2026, especially in the Henley on Thames, Remenham and Medmenham areas. Light rainfall is forecast for today and tomorrow. We are monitoring rainfall and river levels. We are liaising with emergency services and local authorities. Avoid using low lying footpaths and any bridges near local watercourses. Go to River levels online for updates on current river levels. T
Monitoring gauges during this event
| Station | River | Rise | Peak |
|---|---|---|---|
| Sonning Lock | River Thames | +3.34m | 3.50m |
| Boulters Lock | River Thames | +3.29m | 3.34m |
| Marlow Lock | River Thames | +3.21m | 3.64m |
| Marsh Lock | River Thames | +3.13m | 3.27m |
| Shiplake Lock | River Thames | +3.08m | 3.27m |
| Caversham Lock | River Thames | +2.92m | 3.08m |
| Hurley Lock | River Thames | +2.16m | 2.23m |
| Hambleden Lock | River Thames | +0.60m | 0.70m |
| Temple Lock | River Thames | +0.20m | 0.23m |