• Journal of Korea Water Resources Association
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• v.45 no.11
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• pp.1107-1119
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• 2012

The objectives of this study are to develop the flow nomograph for real-time flood forecasting and to assess its applicability in restored Cheonggye stream. The Cheonggye stream basin has the high impermeability and short concentration time and complicated hydrological characteristics. Therefore, the flood prediction method using runoff model is ineffective due to the limit of forecast. Flow nomograph which is able to forecast flood only with rainfall information. To set the forecast criteria of flow nomograph at selected flood forecast points and calculated criterion flood water level for each point, and in order to reflect various flood events set up simulated rainfall scenario and calculated rainfall intensity and rainfall duration time for each condition of rainfall. Besides, using a rating curve, determined scope of flood discharge following criterion flood water level and using SWMM model calculated flood discharge for each forecasting point. Using rainfall information following rainfall scenario calculated above and flood discharge following criterion flood water level developed flow nomograph and evaluated it by applying it to real flood event. As a result of performing this study, the applicability of flow nomograph to the basin of Cheonggye stream appeared to be high. In the future, it is reckoned to have high applicability as a method of prediction of flood of urban stream basin like Cheonggye stream.

• Journal of Korea Water Resources Association
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• v.53 no.3
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• pp.225-236
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• 2020

It is not easy to provide sufficient lead time for flood forecast in urban and small mountain basins using on-ground rain gauges, because the time concentration in those basins is too short. In urban and small mountain basins with a short lag-time between precipitation and following flood events, it is more important to secure forecast lead times by predicting rainfall amounts. The Han River Flood Control Office (HRFCO) in South Korea produces short-term rainfall forecasts using the Mcgill Algorithm for Precipitation-nowcast by Lagrangian Extrapolation (MAPLE) algorithm that converts radar reflectance of rainfall events. The Flash Flood Research Center (FFRC) in the Korea Institute of Civil Engineering and Building Technology (KICT) installed a flash flood forecasting system using the short-term rainfall forecast data produced by the HRFCO and has provided flash flood information in a local lvel with 1-hour lead time since 2019. In this study, we addressed the flash flood forecasting system based on the radar rainfall and the assessed the accuracy of the forecasting system for the recorded flood events occurred in 2019. A total of 31 flood disaster cases were used to evaluate the accuracy and the forecast accuracy was 90.3% based on the probability of detection.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.68-77
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• 2011

Flood disasters on the metropolis where population and facilities were densely concentrated cause an enormous damage, therefore it is important to find risk and vulnerable area for floods, and then mid-long term disaster reduction plan should be established by the results. However, there is no rational method which reflects urban characteristics to estimate the regional safety for flood. so it is necessary to develop the standardized method of regional safety assesment due to urban flood. The proposed regional safety assesment model in this study was combined risk and mitigation score which consisted of three and two element, and 12 assesment factors which effect flood disasters were selected. And then the integrated regional safety was estimated by subtracting mitigation score from risk score. GIS tool was used to estimate the factor assesment and integrated regional safety. Developed regional safety assesment model was applied in Seoul to evaluate the suitability.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.148-153
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• 2016

Hydraulic and hydrological flood routing methods are commonly used to analyze temporal and spatial flood influences of flood wave through a river reach. Hydrological flood routing method has relatively more simple and reasonable performance accuracy compared to the hydraulic method. Storage constant used in Muskingum method widely applied in hydrological flood routing is very similar to the travel time. Focusing on this point, in this study, we estimate the travel time from HEC-RAS results to estimate storage constant, and develop a non-linear regression equation for the travel time using reach length, channel slope, and discharge. The estimated flow by Muskingum model with storage constant of nonlinear equation is compared with the flow calculated by applying the HEC-RAS 1-D unsteady flow simulation. In addition, this study examines the effect on the weighting factor changes and interval reach divisions; peak discharge increases with the bigger weighting factor, and RMSE decreases with the fragmented division.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.797-808
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• 2019

This study evaluated the applicability of spacebourne datasets to the flood analysis in an ungauged watershed where is no discharge measurements. The Duman River basin of North Korea was selected as a target area which was flooded by recent Typhoon Lionrock. Topographical parameters for flood analysis were estimated from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM). GDEM includes the shortcomings of information on river cross-section, and conducted 2 dimensional flood analysis when considering virtual river cross-section and not considering it. As a result of comparative analysis, an error occurs in the inundation area and depth, but when used carefully, it is considered that the satellite image can be used for creating flood hazard map and utilizing information for response and preparation.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.781-796
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• 2019

This study attempted to simulate the flood discharge in the Duman River basin containing Hoeryong City and Musan County of North Korea where were damaged from Typhoon Lionrock on August, 2016. For hydrological modelling remotely sensed datasets were used to estimate watershed properties and hydrologic factors because the basin is ungauged where hydrological observation is not exist or sparse. For validation we applied our methodology and datasets to the Soyanggang Dam basin. It has not only similar shape factor and compactness ratio to those of the target basin but also accurate, adequate, and abundant measurements. The results showed that the flood discharge from Typhoon Lionrock corresponded to three to five years design floods in the Duman River basin. This indicate that the Duman River basin has a high risk of flood in the near future. Finally this study demonstrated that remotely sensed data and geographic information could be utilized to simulate flood discharge in an ungauged watershed.

• Journal of Convergence for Information Technology
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• v.9 no.11
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• pp.125-133
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• 2019

In this paper, probabilistic flood risk maps were produced for levee break caused by possible flood scenarios. The results of the previous studies were employed for flood stages corresponding to hydrological extreme event quantified uncertainties and then predicted the location of a levee breach. The breach width was estimated by combining empirical equation considered constant width and numerical modeling considered uncertainties on compound geotechnical component. Accordingly, probabilistic breach outflow was computed and probabilistic inundation map was produced by 100 runs of 2D inundation simulation based on reliability analysis. The final probabilistic flood risk map was produced by combining probabilistic inundation map based on flood hazard mapping methodology. The outcomes of the study would be effective in establishing specified emergency actin plan (EAP) and expect to suggest more economical and stable design index.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6B
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• pp.605-612
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• 2006

In this study(II), The developed rainfall forecast model was applied to the NakDong River Basin for the heavy rainfall on 6th to 16th of August in 2002. The results demonstrated that the rainfall forecasts of 3 hours lead time showed good agreement with observed data. The inundation aspect of simulation depends on actual levee failure in the same basin. Rainfall forecasts were used for flood amount computation in the target watershed. Also the flood amount in the target watershed was used on boundary condition for flood inundation simulation in a protected lowland and a river. The results of simulation are consistent with actuality inundation traces and flood level data of the target watershed. This study provides practical applicability of satellite data in rainfall forecast of extreme events such as heavy rainfall or typhoon. Also this study presented an advanced integrated model of rainfall, runoff, and inundation analysis which can be applicable for flood disaster prevention and mitigation.

• Journal of Korean Society of Disaster and Security
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• v.6 no.1
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• pp.47-53
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• 2013

Standard Incident Command System in Korea is that Incident Command System for Emergency Rescue Operation, which is commanded only by Fire Fighting Agencies. However, in the event of a disaster such as the flood, storm, or landslide disaster, there are many disaster response activities performed by the General Public Officers at the disaster on-scene. Yet, there isn't an Natural Disaster Command System for the General Public Officers in Korea. Thus, we have studied the response activities needed cooperation among agencies and proposed some considerations of the Natural Disaster Command System for General Public Officers. The system will be useful to response and recover disaster rapidly, seamlessly, and cooperatively among General Public Officers and the related agencies.

• KIEAE Journal
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• v.15 no.1
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• pp.129-137
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• 2015

The purpose of this study is to analyze the Tetsugakudo Kouen Collective Housing Development Project in Japan. Project implemented cooperatively by the Tokyo Metropolitan Government in charge of river management, Shinjuku and Nakano-ku responsible for park management, and the UR, a housing project developer. This project set a significant precedent for three-dimensional river use by realizing the three-dimensional integrated development of a flood control reservoir, a park, and collective housing. The major effectiveness of this project can be summarized into four points. 1) The costs borne by individual project developers were significantly reduced by realizing a high degree of application and multipurpose use of the land through a joint project. 2) This project, which was designed to accommodate rainfall of 30 to 40mm per hour, is expected to contribute to reducing flood damage and generating significant investment effects, in terms of asset value in downstream areas, thereby increasing flood control security. 3) Local disaster prevention function were enhanced by providing an evacuation site in the case of an earthquake. 4) The living environment was improved by adding the function of a park.