Flood Warnings in Hertfordshire
Hertfordshire flood warnings including the River Lea and River Colne catchments.
Data from the Environment Agency. Last updated:
Active Flood Warnings
River Thame, Horsenden Stream, Chalgrove Brook
High river levels may lead to flooding. River levels are high on the Chalgrove Brook through Chalgrove. River levels along the River Thame are below the flood risk threshold. Flooding of low lying land and roads in the Chalgrove area remains possible today, 16 March 2026. The forecast is for a mostly dry day today and a dry day tomorrow. We expect levels to remain high over the coming days. River levels are sensitive to further rainfall. We are monitoring rainfall and river levels. Avoid low lying footpaths and roads near rivers, which may be flooded. Go to River Levels Online for updates on current river levels. This message will be updated by 6:00PM on 16 March 2026, or as the situation changes.
Frequently Asked Questions
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