• Journal of Korean Society of Rural Planning
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• v.23 no.3
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• pp.21-36
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• 2017

Climate change is intensifying storms and floods around the world. Where nature has been destroyed by development, communities are at risk from these intensified climate patterns. This study was to suggest a methodology for estimating flood vulnerability using Potential Flood Damage(PFD) concept and classify city/county about Potential Flood Damage(PFD) using various typology techniques. To evaluate the PFD at a spatial resolutions of city/county units, the 20 representative evaluation indexing factors were carefully selected for the three categories such as damage target(FDT), damage potential(FDP) and prevention ability(FPA). The three flood vulnerability indices of FDT, FDP and FPA were applied for the 167 cities and counties in Korea for the pattern classification of potential flood damage. Potential Flood Damage(PFD) was classified by using grouping analysis, decision tree analysis, and cluster analysis, and characteristics of each type were analyzed. It is expected that the suggested PFD can be utilized as the useful flood vulnerability index for more rational and practical risk management plans against flood damage.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.63-73
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• 2010

This study is to develop a downstream flood damage prediction model for efficient confrontation in case of extreme and flash flood by future probable small agricultural dam break situation. For a Changri reservoir (0.419 million $m^3$) located in Yongin city of Gyeonggi province, a dam break scenario was prepared. With the probable maximum flood (PMF) condition calculated from the probable maximum precipitation (PMP), the flood condition by dam break was generated by using the HEC-HMS (Hydrologic Engineering Center - Hydrologic Modeling System) model. The flood propagation to the 1.12 km section of Hwagok downstream was simulated using HEC-RAS (Hydrologic Engineering Center - River Analysis System) model. The flood damaged areas were generated by overtopping from the levees and the boundaries were extracted for flood damage prediction, and the degree of flood damage was evaluated using IDEM (Inundation Damage Estimation Method) by modifying MD-FDA (Multi-Dimensional Flood Damage Analysis) and regression analysis simple method. The result of flood analysis by dam-break was predicted to occurred flood depth of 0.4m in interior floodplain by overtopping under PMF scenario, and maximum flood depth was predicted up to 1.1 m. Moreover, for the downstream of the Changri reservoir, the total amount of the maximum flood damage by dam-break was calculated nearly 1.2 billion won by IDEM.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.5
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• pp.87-92
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• 2009

It has been considered only with the concerned regional damage costs whenever the restoration and flood control measures were established in Korea. If the relationship between regional flood frequency and damages is quantitatively analyzed, more resonable and reliable countermeasure for flood protection and restoration can be proposed. Historical data ('70~'07) about flood damage in Korea were utilized and analyzed to present such relationship using the point frequency analysis. Also, the quadrant analysis was employed to divide into 4 categories: high frequency-high damage, high frequency-low damage, low frequency-high damage, and low frequency-low damage. If the results from this study were utilized well in specific cities and counties in Korea, it would be helpful to establish the countermeasures and action plans for flood protection because it was possible to compare with the relationship between flood frequency and damage of each region. And it would be the fundamental data for estimating the effect of future flood protection plan.

• Journal of Korea Water Resources Association
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• v.50 no.8
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• pp.513-520
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• 2017

In order to analyze flood damage mitigation effects, it is necessary not only to analyze inundation areas and depth through hydraulic and hydrological analysis but also to estimate flood damages. Flood damages of structure and contents of buildings are generally analyzed according to the flood depth. In this study, we developed and applied flood depth-damage functions for the school buildings based on actual damage data. In addition, the development and modification procedure of flood depth-damage functions for school buildings is presented in this paper, and the developed damage functions are verified by comparing them with the existing method. It is expected that the process of developing and applying flood depth-damage functions presented in this study can be used in the cost benefit analysis of flood damage mitigation measures.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.163-163
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• 2023

Flooding has become an increasing event which is one of the major natural disasters responsible for direct economic damage in South Korea. Driven by climate change, precipitation extremes play significant role on the flood damage and its further increase is expected to exacerbate the socioeconomic impact in the country. However, the empirical evidence associating changes in precipitation extremes to the historical flood damage is limited. Thus, there is a need to assess the causal relationship between changes in precipitation extremes and flood damage, especially in agricultural region like Chungcheong region in South Korea. The spatial and temporal changes of precipitation extremes from 10 synoptic stations based on daily precipitation data were analyzed using the ClimPACT2 tool and Mann-Kendall test. The four precipitation extreme indices consisting of consecutive wet days (CWD), number of very heavy precipitation wet days (R30 mm), maximum 1-day precipitation amount (Rx1day), and simple daily precipitation intensity (SDII), which represent changes in intensity, frequency, and duration, respectively, and the time series data on flooded area and flood damage from 1985 to 2020 were used to investigate the causal relationship in the ARDL-ECM framework and pairwise Granger causality analysis. The trend results showed that majority of the precipitation indices indicated positive trends, however, CWD showed no significant changes. ARDL-ECM framework showed that there was a long-run relationship among the variables. Further analysis on the empirical results showed that flooded area and Rx1day have significant positive impacts on the flood damage in both short and long-runs while R30 mm only indicated significant positive impact in the short-run, both in the current period, which implies that an increase in flooded area, Rx1day, and R30 mm will cause an increase in the flood damage. The pairwise Granger analysis showed unidirectional causality from the flooded area, R30 mm, Rx1day, and SDII to flood damage. Thus, these precipitation indices could be useful as indicators of pluvial flood damage in Chungcheong region of South Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.363-369
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• 2006

A simple and an improved methods for the economic analysis of the flood control project has been in previous studies in Korea. In 2004, the Multi-Dimensional Flood Damage Analysis (MD-FDA) was developed and now it is widely used for the economic analysis of flood control project. However, the MD-FDA was developed for general damage assessment and analysis without consideration of specific regional characteristics such as urban and rural areas. To compensate the MD-FDA for the application in urban area, a part of damage estimation components is modified and a component for the flood damage estimation is suggested. The component we suggest is for the consideration of the capability of stormwater pump stations in the study area. When flood is occurred in the urban area, the damage potential is larger than the rural area because of the concentration of human lives and properties. So, many stormwater pump stations are located in the urban area and the inundation depth is estimated by considering the capabilities of pump stations. We also compensate the damage components such as the damages of industrial area, and public facilities for the flood damage estimation of the urban area. The results by the compensated MD-FDA for the urban area application with those by original MD-FDA are compared. As a result the B/C ratio showed 6.75 and 5.51 respectively for the modified and original MD-FDA. This difference might be largely affected by the damage rate of the public facilities.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3B
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• pp.301-310
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• 2006

Typically, we needs enormous national budget for the flood control project and so the project usually has big influence on the national economy. Therefore, the reliable estimation of flood damage is the key issue for the economic analysis of the flood control project. This study aims to provide a GIS based technique for distributed flood damage estimation. We consider two aspects of engineering and economic sides, which are the inundation analysis and MD-FDA (Multi-Dimensional Flood Damage Analysis), for the flood damage assessment. We propose the analysis framework and data processing using GIS for assessing flood damages. The proposed methodology is applied to the flood control channel project for flood disaster prevention in Mokgamcheon/Dorimcheon streams and this study presents the detailed GIS database and the assessment results of flood damages. This study may have the worth in improving practical usability of MD-FDA and also providing research direction for combining economic side with the engineering aspect. Also this distributed technique will help decision-making in evaluating the feasibility of flood damage reduction programs for structural and nonstructural measures.

• Journal of Wetlands Research
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• v.22 no.4
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• pp.302-311
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• 2020

There are limitations to cope with flood damage by structural strategies alone because both frequency and intensity of floods are increasing due to climate change. Therefore, it is one of the necessary factors in the nonstructural countermeasures to collect and analyze historical flood damage records for the future flood damage assessments. In order to estimate flood damage costs in Gyeongsangbuk-do where severe flood damage occurs frequently due to geographical and climatic effects, this paper has performed the regression analysis on flood damage records over the past 20 years (1999-2018) by rainfall characteristics, which is one of the major causes of flood damage. This paper has then examined the relationship between the terrain features and rainfall characteristics in the regional regression functions, and also estimated the flood damage risk for 100-year rainfall by using the regional regression functions presented for the 22 administrative districts in Gyeongsangbuk-do excluding Ulleung-gun. The flood damage assessment shows that the relatively high damage risk is estimated for county areas adjacent to the eastern coast in Gyeongsangbuk-do. The regional damage estimate functions in this paper are expected to be used as one of the nonstructural countermeasures to estimate flood damage risk for the design or forecasting rainfall data.

• Journal of Korea Water Resources Association
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• v.50 no.6
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• pp.397-405
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• 2017

In case of inundation in a city where populations and properties are highly concentrated, unlike rural areas it is necessary to apply the method of calculating the damage amount considering the sewage overflow and the corresponding building damage. In this study, Dorim 1 drainage sector has been analyzed with Multi-Dimensional Flood Damage Assessment (MD-FDA) for flood forecast. It is analyzed with past flood history through the SWMM model and calculated the amount of damage with district base data and the result of flow analysis. The result of the SWMM model to predict a range of flood, it was shown that the wide area after 4 hours (at 16:30) by sewer overflow. The building damage was estimated using MD-FDA. As a result, the maximum flood area has shown as $205,955m^2$ (0~0.5 m: $205,190m^2$, over 0.5 m: $865m^2$) and estimated building damage of Dorim 1 drainage sector is approximately 15.5 billion KRW (Korean won) and other contents is 7 billion KRW (Korean won). Also from 0 to 0.5 m depth estimated damage is approximately 22.4 billion KRW (Korean won) and over 0.5 m is 100 million KRW (Korean won). Based on the results of this study, it would be necessary to estimate the amount of sub-divided flood damage in urban areas according to various damage patterns such as flood depth and flood time.

• Water Engineering Research
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• v.3 no.4
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• pp.215-234
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• 2002

Uncertainty in dam breach flood routing results was analyzed in order to provide the basis fer the investigation of their effects on the flood damage assessments and dam safety risk assessments. The Monte Carlo simulation based on Latin Hypercube Sampling technique was used to generate random values for two uncertain input parameters (i.e., dam breach parameters and Manning's n roughness coefficients) of a dam breach flood routing analysis model. The flood routing results without considering the uncertainty in two input parameters were compared with those with considering the uncertainty. This paper showed that dam breach flood routing results heavily depend on the two uncertain input parameters. This study indicated that the flood damage assessments in the downstream areas can be critical if uncertainty in dam breach flood routing results are considered in a reasonable manner.