LiDAR DEM Data for Flood Mapping and Assessment; Opportunities and Challenges: A Review

摘要

Flooding is the most catastrophic, wide spread, and frequent natural hazards causing extensive damages on infrastructure, human life, and the environment. The frequency and severity of flooding has been increasing all over the world attributed to climate change and escalated urbanization. As such, the issue and techniques of monitoring and mapping flood inundated areas are also increasing. Advancement of state-of-the-art technologies have facilitated and improved flood mapping and monitoring. Earth observation plays important role in flood mapping, monitoring, and damage assessment. However, there are fundamental issues that restricts satellite data from being used for flood studies. LiDAR DEM data based flood modeling approach solves some of the limitations of Earth observation. On the other hand, flood modeling using LiDAR DEM data are challenging. The aim of this review is, therefore, to identify the opportunities and challenges of using LIDAR DEM data for flood mapping and assessment. Substantial literature review was done to attain the stated objective. The study revealed that flood modeling techniques could significantly improve the limitations of detecting flood using Earth observation such as detecting flooded areas under dense canopies and in urban areas. This is attributed to the accurate and fine resolution LiDAR DEM. Furthermore, LiDAR technology provide several opportunities such as relatively cost and time effective data collection system, capability of penetrating dense vegetation, and improved flood model accuracy and fine scale flood modeling. On the other hand, LiDAR data filtering (classification), data availability and accessibility, data file size, high computational time, inability to characterize channels bathymetry, and insufficiency of representing complex urban features are some of the challenges. Therefore, multi-platform LiDAR data (i.e., ground-based, airborne and space borne) and data from additional sources such as echo soundings and electronic theodolite surveys should be integrated to increase the effectiveness of the LiDAR technology for flood modeling.