• 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.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.2
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• pp.15-25
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• 2004

For the effective operation of irrigation reservoirs, a general and systematic policy is suggested to make balance of the conflicting purposes between water conservation and flood control. In this study, the flood effective analysis system was developed through the integration of long-term water budget analysis model, GIS-based HEC-HMS model and HEC-RAS model. The system structure consists of long-term water budget model using modified TANK theory, flood runoff and flood effects analysis model using HEC-GeoHMS, HEC-HMS and HEC-RAS models. The flood effects analysis system simulated the flood runoff from the upstream, downstream flood and long-term runoff of the watershed using the observed data collected from 1998 to 2002 of Seongju dam. The simulated results were reasonably good compared with the observed data. The optimal management method of the reservoir during the whole season is suggested in this study, and the flood analysis system can be a useful tool to evaluate a reservoir operation quantitatively for the mitigation of flood damages of reservoir basin.

• Journal of Korea Water Resources Association
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• v.43 no.5
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• pp.495-505
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• 2010

The integrated basin-wide flood mitigation planning has a numerous individual proposals with different characteristics. So, it makes difficult to develop the optimal alternative that combines such elements. To develop the optimal alternative, it's necessary not only to assess the flood damage but also to define a tolerable degree of damage. Such a definition is made in a way, dubbed the 'social consensus' in a broad sense; but initially, it requires the analysis of the economic efficiency within a scope, which is technically achievable. This study aims to propose the alternatives development method so that the combination of the individual proposals could be economically efficient. To this end, this study defined the flood mitigation projects as the economic production activities carried out by inputs and outputs, and proposed the optimal project size as the principle of developing alternatives. This study may have the worth in improving the alternatives development method by considering the optimal project scale from the economic viewpoint while the existing method depending on engineering aspect. Such approach is expected to correspond to the current government's policy that avoids the passive flood mitigation focused on channel-wide planning but pursues the basin-wide flood mitigation planning focusing on damaged area, thereby provide efficient tools to come up with the solution.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.637-640
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• 2008

Flood control and river improvement works are carried out every year for the defense of the flood disaster, it is impossible to avoid the damage when there is a flood exceeding the capacity of hydraulic structures. Therefore, nonstructural counter plans such as the establishment of flood hazard maps, the flood warning systems are essential with structural counter plans. In this study, analysis of the internal inundation effect using rainfall runoff model such as PC-SWMM was applied to Woo Ee experimental stream basin. Also, the design frequency analysis for effects of the external inundation was accomplished by main parameter estimation for conclusive hydraulic routing using HEC-RAS model. Finally, inundated areas for flood hazard map were estimated at Woo Ee downstream basin according to flood frequency using HEC-GeoRAS model linked by Arc View GIS.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.151-158
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• 2009

Many people have been suffering and loosing their property from inundation due to concentrated rain and massive storm. Although, river banks are strengthened and pumping stations are constructed to protect the life and property of people, the flood damages (disaster)could not be controlled, in fact it is increasing. In USA, CWMS (Corps Water Management System) has very good system of integration of study of rainfall data, computation of stream stage and simulation of flood damages, but there is lack of this type of study and analysis in the domestic context, so we have been facing many difficulties in simulation of flood damages. Therefore, a systematic collecting of data analysis and evaluation of flood damages is necessary. The main objective of this study is to suggest a systematic data collection and evaluation method, which could be useful to prevent the life and property from unusual damages. In this study, the system (Flood Damage Evaluation Model; K-FDEM) is proposed to evaluate the flood damages from rainfall with considering many field parameters.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.123-133
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• 2010

Due to climate change and difficulty in construction of large dam, it is on the increase to use small hydraulic facilities such as washland for the flood control purpose. Since there can be many potential locations for washland in a basin, it is important for determination of optimal location to calculate flood reduction effect of washlands substantially and exactly. In this study, a new scheme to increase flood reduction effect of washlands is suggested. Suggested scheme uses sensitivity analysis of flood reduction effect depending on washland characteristics such as storage volume, spillway elevation and spillway width. The characteristics of the washland is determined by results of sensitivity analysis to maximize flood reduction effect at basin outlet and downstream of a washland. The methodology is applied to Anseong river basin to show its applicability and applied result is compared with those of another studies.

• Journal of Korea Water Resources Association
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• v.39 no.11 s.172
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• pp.915-922
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• 2006

National Emergency Management Agency is planning a flood disaster mitigation system in urban area. This research is about analysis of runoff reduction efficiency of the alloted detention system which is one of flood disaster mitigation systems in urban area. The alloted detention system is composed of small to middle size detention facilities located in up and middle stream of urban basin. To analyze runoff reduction efficiency of alloted detention system, basic runoff analysis in test area has been carried out and runoff characteristics with size and locations of detention facilities has been simulated. The results of simulation are showing that alloted detention system can reduce the discharge of main stream and detention facilities' size and locations are major parameters of runoff reduction efficiency. It is concluded that alloted detention system can be a useful method in urban area's flood disaster mitigation and can secure safety against flood damages in urban areas.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.3 s.10
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• pp.125-132
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• 2003

In this study, safety analysis of river in flash flood due to local extraordinary rainfall was conducted for the Hong-Je river, which was selected as a representative sample basin because it is one of the most urbanized rivers in Seoul. The rainfall data of precipitation 310.1 mm and probable maximum precipitation (PMP) 740.0 mm in July $14{\sim}15$, 2001 was used to perform safety analysis. Resulting of safety analysis of the flood control in Hong-Je river, case of the 50 year of design frequency, safety section, management section, and danger section were represented to be 85%, 15%, and 0% respectively. For the 200 year of design frequency, safety section decreased by 6% and management section and danger section increment by 4% and 2%, respectively, The variation of management section was not observed with respect to 200 year of frequency. Little variation of safety value for management section for 300 and 500 of frequency increased by 8% and 12% relative to 50 year of frequency, respectively. management section and danger section for 1000 year of frequency increased by 19% and 13% relative to 50 year of frequency.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.571-574
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• 2007

The purpose of this research is to analyze sensitivities on hydraulic characteristic factors of bridge and culvert causing flood water level rising. With HEC-RAS and RMA2 models, analysis of backwater due to bridge and culvert in an ideal stream was carried out. The results of hydraulic modeling and sensitivity analysis indicated that the opening ratio and the Froude number were the most sensitive factors and other factors were not quite sensitive to flood water level rising.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.140-148
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• 2010

The Taihu Basin is located in the east coast of China, where the threats of frequent floods have induced construction of massive, complex, hierarchical flood defense systems over the interconnected river networks. Digital modeling of flooding processes and quantitative damage assessment still remain challenging due to such complexity. The current research uses an integrated approach to meet this challenge by combining multiple types of models within a GIS platform. A new algorithm is introduced to simulate the impacts of the flood defense systems, especially the large number of polders, on floods distributions and damages.