39% AEP Flood Depths with Recent Development Area

The 39% AEP flood depth map represents depths from a flooding and storm tide event with 39% chance of occurring or being exceeded each year. The flood depth map may not provide an accurate guide of the flood hazard at a given location, due to the absence of velocity information. Flood hazard, which incorporates both depth and velocity characteristics, can be viewed in the 39% AEP Flood Hazard map. Ground levels used to inform the mapping include: - 2014 LiDAR as the base terrain; - 2022 LiDAR covering urban areas; and - 2022 LiDAR covering earthworks which occurred between 2014 and 2022 outside of urban areas. Recent Development Areas highlight locations where flood information is likely to have changed due to development that has occurred since the underlying mapping was prepared. Recent Development Areas are represented by a -99 value in this layer.39%年超概率（Annual Exceedance Probability, AEP）洪水深度图，表征的是每年发生或被超越概率为39%的洪水与风暴潮事件对应的水深。 由于未包含流速信息，该洪水深度图无法精准反映特定点位的洪水灾害风险。同时涵盖水深与流速特征的完整洪水灾害风险，可通过39% AEP洪水灾害风险图查看。 本次制图所采用的地面高程数据源包括： - 以2014年激光雷达（Light Detection and Ranging, LiDAR）作为基础地形数据； - 覆盖城区范围的2022年激光雷达数据； - 覆盖2014至2022年间城区外土方工程区域的2022年激光雷达数据。 近期开发区指的是自基础制图工作完成后，因后续开发建设导致洪水相关信息大概率发生变化的区域。 本图层中，近期开发区以-99值进行标识。