PPS 15 Planning and Flood Risk (Revised)·Page 30·6.3
Coastal Tidal Flood Plain Definition
Defines the coastal flood plain as the area where a flood event with 1 in 200 year probability (0.5% annual probability) would exceed peak floodwater levels, caused by high tide, surge, wave action and sea level rise.
A coastal flood plain is a generally flat area adjacent to the shoreline where water flows in time of flooding, attributed to the combination of high tide levels, surge, wave action and sea level rise or would flow but for the presence of coastal flood defences. Coastal (Tidal) Flood Plain – the extent of a flood event with a 1 in 200 year probability (or 0.5% annual probability) of exceeding the peak floodwater level.
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