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Flooding is possible - be prepared

Flood alert for River Mimram in Hertfordshire

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Flooding is affecting low lying land, roads and gardens close to the River Mimram, due to persistent rainfall in December and January, leading to high groundwater levels.

We are monitoring the flooding that is currently affecting the Fulling Mill Lane, Singlers Marsh, and Codicote Road areas in Welwyn.

There is elevated risk of flooding caused by water emerging from a third party blocked culvert. Flooding to homes and businesses is unlikely at this time, but there may be a risk to very low-lying properties or those with basements. River levels in other areas remain below levels of concern.

Some rainfall is possible from Friday 7 March and over the weekend although rainfall totals are not expected to be of concern.

Avoid using low lying footpaths and any bridges near local watercourses and do not attempt to walk or drive through flood water. We are continuing to monitor the situation.

This message will be updated by 5pm, Wednesday 12th March 2025, or as the situation changes.

Flood alert area: The River Mimram at Whitwell, Welwyn, Tewin, Hertingfordbury and Hertford.

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