PPS 15 Planning and Flood Risk (Revised)·Page 33·6.17
Definition of Undefended Areas
Undefended areas are flood plain locations without flood defence protection, typically covering the majority of fluvial and coastal flood plains, and experience higher flood risk than defended areas although flooding patterns are more predictable.
An 'Undefended Area' is an area within the flood plain that is not protected by flood defences. This applies to the vast majority of fluvial and coastal flood plains. Undefended areas are at much higher flood risk than defended areas, although the flooded areas are usually more predictable and flood water usually recedes more quickly.
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