• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.1
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• pp.131-140
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• 1992

For a real-time flood forecasting and reservoir control problem of a multipurpose dam, the online acquisition of hydro-meteorological data and computerized analysis of the acquired data are absolutely necessary for the prompt decision of reservoir discharges which can minimize the possible damages and simultaneously maximize the utilization of the runoff. By introducing a man-machine interface such as condensed color graphics of the analyzed results, it is much easier and faster to transform the information to the decision maker who can decide the reservoir discharge. The newly developed PC-REFCON, which represents the PC based real-time flood forecasting and reservoir control, can easily handle the above problems by adopting a innovative decision support system. The system has three principal components of, a data base subsystem which acquires and manages real-time data, a model subsystem which forecasts the flood runoff and simulates the reservoir operation, and a dialogue subsystem which helps decision maker and system engineers using various graphics and tables with renovative methodologies. The developed PC-REFCON will be utilized from the coming Summer of 1992 for the flood control of all the nine multipurpose reservoirs in Korea.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.6
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• pp.109-118
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• 2003

As a fundamental research to establish a safety operation plan for irrigation dams, this study presents hydrologic analysis conducted in Sungju Dam watershed based on various rainfall data. Especially those reservoirs without flood control feature are widely exposed to the risk of flooding, a safe and optimized operation program need to be improved against arbitrary flooding. In this study, reservoir routing program was developed and simulated for reservoir runoff estimation using WMS hydrology model. The model simulated the variations of reservoir elevation under the condition of open or closed emergency gate. In case of closed emergency gate, water surface elevation was given as 193.15 m, and this value exceeds the dam crest height by 1.65 m. When the emergency gate is open, the increment of water surface elevation is given as 192.01 m, and this value exceeds dam crest height by 0.57 m. As an alternative plan, dam height increase can be considered for flood control under the PMP (Probable Maximum Precipitation) condition. Since the dam size is relatively small compare to the watershed area, sound protection can be expected from the latter option rather than emergency gate installation.

• Water for future
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• v.23 no.4
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• pp.499-507
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• 1990

Real-time reservoir operation models during flood period require optimization of hourly releases from the input data through on-line system. And predicted values. An algorithm of the simulation model to resolve the problem has already been reported with formulation of objectives to minimize the flood damage in downstream reaches and to conserve water at the end of operation for the later use. This paper presents an application of the model to a single reservoir system at the Daecheong Dam during flood and the results are reviewed. This paper also reviews measured inflows and releases in the past. The model is applied to the flood hydrographs of several return periods assuming different reservoir levels at the beginning of the operation. Also it demonstrates the simulation of test run with inflow forecasts obtained by rainfall-runoff model and compares the results. As a result, the model can use efficiently the flood control capacity with consideration of risk factor for the uncertainties associated with inflow forecasts.

• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.639-650
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• 2002

Reservoir operations during the flood season should consider both the flood control and water supply objectives. This study proposed Set Control Algorithm (SCA) as a reservoir operation method, which guarantees both objectives. The concept behind SCA is to provide operators with a set of actions that guarantee feasibility, given a set of operational constraints, and to let them select decisions within a set that satisfies other considerations. The inflow sets used in this study included; observed data, synthetic data, and ESP(Ensemble Streamflow Prediction) scenarios. Applied to the Chungju Dam operations, SCA was compared to the variable flood restricted elevation, as well as the current flood restricted elevation. A 5-year simulation analysis showed that SCA performed better than the other operation methods, and that SCA coupled with ESP performed best among the SCA cases.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.291-294
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• 2003

The Water resources utilization pattern of Jangsung reservoir was studied. The observed precipitation and existing reservoir operation data such as irrigation amount, reservoir storage, river maintenance requirement, flood control discharge were collected for ten years period and analyzed. Major findings of this study are as follows: The observed average, minimum, maximum annual precipitation were 905.1mm, 1,977.3mm, 1,554.3mm during study period, respectively. The average annual irrigation amount was 554.5mm, irrigation amount of drought years of '92 and '94 was 604.6mm, 679.2mm, respectively. However, irrigation amount of extended drought year '95 was 384.9mm. It showed that supplying capacity of Jangsung reservoir was limited when consecutive 2 year drought occurred. The main water resources usage of Jangsung reservoir was irrigation, but flood control discharge exceed irrigation amount exceptionally when high precipitation occurred. The reservoir operation record revealed that discharge for river maintenance was delivered even drought years.

• Water for future
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• v.28 no.6
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• pp.217-228
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• 1995

For optimal reservoir operation during flood period, a general and systematic policy is suggested to make balance of the conflicting purposes between water conservation and flood control. The purpose of this study is to decide the restricted water level of the reservoir during flood period specially to meet water demand in non-flood period. The optimal policy is derived by reallocation of storage capacity through the application of variable restricted water level(VRWL) and minimum required water level(MRWL) for shorter intervals. This study also suggests water level dconditions to secure conservation storage capacity at the end of the flood period estimated by reservoir operation study. This paper illustrates an application of the Daecheong Dam and Chungju Dam respectively during flood and the results are reviewed.

• Water Engineering Research
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• v.5 no.4
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• pp.157-176
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• 2004

This research presents a prototype development and implementation of Decision Support System (DSS) for integrated river basin water management for the flood control. The DSS consists of Relational Database Management System, Hydrologic Data Monitoring System, Spatial Analysis Module, Spatial and Temporal Analysis for Rainfall Event Tool, Flood Forecasting Module, Real-Time Operation of Multi Reservoir System, and Dialog Module with Graphical User Interface and Graphic Display Systems. The developed DSS provides an automated process of alternative evaluation and selection within a flexible, fully integrated, interactive, centered relational database management system in a user-friendly computer environment. The river basin decision-maker for the flood control should expect that she or he could manage the flood events more effectively by fully grasping the hydrologic situation throughout the basin.

• Water for future
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• v.18 no.3
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• pp.225-233
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• 1985

To develop a simulation strategy of multi-reservoir operation in flood season, the single dam operations methed for the Chungju dam are investigated in the Han river basin. Thus, spillway rule curve, rigid ROM, and linear decision rules are applied for control operations, subject to the restrictions imposed by the river and the reservoir characteristics. The storage and release and control/utility efficiencies for several floods are calculated. The variation of control coefficients with respect to the return period are also examined. As the results of this comparative study, the optimal operation method can be selected in terms of the magnitude of flood. With inflow forecasting, the flood control operation can be greatly improved by variable coefficients rigid ROM and linear decision rules.

• Water for future
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• v.25 no.2
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• pp.47-60
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• 1992

An optimal operation model for flood control of multi-reservoirs, Hwacheon and Soyanggang, located in the north Han River basin is developed by using the Incremental DP. The objective function is to minimize the peak flow at the confluence point, of Euam dam, and the hydraulic and hydrologic constraints are established by considering the related laws as to the operation of dam in flood season, each reservoir and channel characteristics. In particular, the final elevations of each reservoir are induced to the conservation pool level in order to prepare for the secondary flood. In addition, the results of this model, simulation results and the single reservoir operation by DP are compared in terms of control and utility efficiencies, and also the peak flows at the confluence point for floods with various return periods are compared with the results of simulation suing feedback control. as the results, the control and utility effciencies are more or less low in contrast with the results of simulation and the single reservoir operation by DP, and the peak flows at confluence point are high because of terminal condition of reservoir storage.

• Journal of Environmental Science International
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• v.17 no.6
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• pp.601-609
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• 2008

In this study for the development of area due to the increasing of industry, population and spreading of urbanization is rapidly increasing but about seventy percent of our nation's areas consists of the mountainous districts. In such case, when those areas have the heavy rains break, they are washed away by a fast-flowing stream of a valley and overflowed. Thus it could result on human life and property damage and also the widespread of flood damage in the downstream area. To decrease those damage, the construction of flood control reservoir is necessary. This research was aim to construct the flood runoff models of a mountainous small district and to determine the probability rainfall by analyzing precipitation. The study also examined the effects of location and size of flood control reservoir on flood reduction. The result showed that the construction of detention basin was an effective way to ensure the safety of flood control and multiple detention basin had superior result for reducing amount of runoff in the down stream area than the single detention basin.