Residential Flood Loss Assessment and Risk Mapping from High-Resolution Simulation

Abstract

Since the patterns of residential buildings in the urban area are small-sized and dispersed, this study proposes a high-resolution flood loss and risk assessment model to analyze the direct loss and risk impacts caused by floods. The flood inundation simulation with a fine digital elevation model (DEM) provides detailed estimations of flood-inundated areas and their corresponding inundation depths during the 2016 Typhoon Megi and 2017 Typhoon Haitang. The flood loss assessment identifies the impacts of both events on residential areas. The depth-damage table from surveys in the impacted area was applied. Results indicated that the flood simulation with the depth-damage table is an effective way to assess the direct loss of a flood disaster. The study also showed the effects of spatial resolution on the residential loss. The results indicated that the low-resolution model easily caused the estimated error of loss in dispersed residential areas when compared with the high-resolution model. The analytic hierarchy process (AHP), as a multi-criteria decision-making method, was used to identify the weight factor for each vulnerability factor. The flood-vulnerable area was mapped using natural and social vulnerability factors, such as high-resolution DEM, distance to river, distance to fire station, and population density. Eventually, the flood risk map was derived from the vulnerability and flood hazard maps to present the risk level of the flood disaster in the residential areas.

Flood Hazard, Vulnerability and Risk Assessment for Different Land Use Classes Using a Flow Model

“…The application of hydraulic model in flood hazard assessment is becoming popular. We can mention the studies by Afifi et al (2019), Zin et al (2018), and Tyrna et al (2018) that applied different hydraulic models in studying flood hazard. At the same time, land use-based and communitybased flood vulnerability study is also getting prioritised.…”

“…The focus of the flood risk of this study is the Baniachong Upazila (Sub-district), one of the flood-affected Upazilas in Bangladesh. Adopting the hydrodynamic behaviour certainly increases the accuracy of flood hazard map (Afifi et al 2019), thereby ensuring better accuracy in flood vulnerability and risk maps. This study applied a 2D hydrodynamic model for the purpose of producing flood hazard map at different return periods of floods in the study site.…”

Real-Time Prediction of the Water Accumulation Process of Urban Stormy Accumulation Points Based on Deep Learning

“…These urban flood simulation models have achieved good results in urban flood simulation and risk analysis by building different modules, such as runoff yield, confluence, and channels [35], [36], [37]. In addition, with the improvement of computer capabilities and the development of geographic information system (GIS) technology, the spatial resolution of surface data has been significantly improved in recent years, and the division of the model spatial scale has become increasingly detailed [38], [39]. However, there is no consensus on how to divide the spatial scale in hydrological simulation [40], [41].…”

Performance Evaluation of Drainage System in Shire Endaslasse Town, Northern Ethiopia

“…Across the world, flood is amongst the most devastating natural disaster, which caused loss of human lives and threats to infrastructure, the environment, and public services [1][2][3].The hydrological balance is affected by factors as the rapid growth of settlements and irregular urbanization on population increases and industrialization in developing countries, particularly in Ethiopia [4,5].The evolution of land use is much related to urban development and increment of flood derived from it due to increasing proportion of the total land areas becomes covered with impermeable surface and decreasing the infiltration of water to the ground. Urbanization covers a large part of the ground with roofs, roads, and pavements and increases the rate of runoff.…”