Flood Alert Issued for Upper River Colne and Radlett Brook in Hertfordshire
This alert is no longer in effect.
Environment Agency issued it on April 6, 2026, 4 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this Environment Agency flood warning directly from Environment Agency's official public data feed. See our methodology for full source attribution and refresh cadence.
The Environment Agency has issued a flood alert for the Upper River Colne and Radlett Brook, warning of potential flooding on low-lying land and roads through February 16, 2026.
Read this weather record in 30 seconds
- Record type
- Flood Alert
- Affected area
- Hertfordshire, England
- Issued
- April 6, 2026
- Issuing authority
- Environment Agency
Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.
Record status: historical. It was issued 4 months ago; use the issuing agency's live warning service for current conditions in Hertfordshire, England.
Alert Details
The Environment Agency has issued a flood alert for the Upper River Colne and Radlett Brook. This alert, classified as severity level 3, indicates that flooding is possible in the designated area. The alert was officially raised at 4:42 PM on February 15, 2026.
Affected Areas
The alert covers the Hertfordshire and North London region, specifically focusing on the Upper River Colne and Radlett Brook. According to the Environment Agency, the locations most likely to be affected include low-lying land and roads near rivers in the following areas:
- Waterside
- Lowbell Lane
- London Colney
- Warrengate Road
What You Should Do
Residents and commuters in the affected areas are advised to take the following precautions:
- Take care when traveling through the region.
- Avoid walking, cycling, or driving through flood water.
- Monitor local weather reports and river levels closely.
Expected Conditions
River levels remain high and are expected to lead to potential flooding. The primary hazard is the inundation of roads and low-lying land adjacent to the River Colne and Radlett Brook.
Timeline
The flood alert is effective from February 15, 2026, into February 16, 2026. The Environment Agency is monitoring the situation and expects to provide an update by 9:00 AM on February 16, 2026, or sooner if conditions change significantly.
Original source: Environment Agency Official Notice ↗
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