Spatial decision support system for integrated river basin flood control

Abstract

Flood has caused the most prevalent and costly natural disasters in the world. Flood also causes impacts to society that go beyond cost and facilities; including impacts such as family and community disruptions, dislocation, injuries and unemployment. During the real-time flood events, the operation of water surface system is very important and crucial to minimize the impacts of flood. This research presents a comprehensive methodology focused on improving current approaches of flood forecasting and control systems using the enhanced technologies, neural network algorithm and multidimensional dynamic programming. The developed methodology has been embedded in a PC based Spatial Decision Support System (SDSS) for integrated river basin flood control. For implementing the prototype of SDSS, several submodules and subsystems have been developed. The SDSS 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 Multireservoir System, and Dialog Module with Graphical User Interface and Graphic Display Systems. The prototype system is intended to demonstrate the potential value of a SDSS to the water resources manager and engineer for operational flood management. The developed SDSS 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 he could manage the flood events more effectively by fully grasping the hydrologic situation throughout the basin. The detailed contribution of each module is as follows: 1. The relational database management system serves center of the spatial decision support system and generating the necessary data files for various modules in the system. 2. The GIS module contributes by minimizing the time required for spatial analysis to generate the isohyet of each time period, as well as new information of the spatial characteristics in the basin. 3. The rainfall-runoff models can be easily constructed beforehand without a lot of knowledge of the underlying process using a neural network algorithm. The developed rainfall-runoff models can better forecast the discharges in accuracy for the proposed points throughout the basin. 4. The power of using dynamic programming for real-time operation of multireservoir should give the more assurance to the operational decision-maker providing quantitative information rather than qualitative information. 5. The graphical user interface should serve the great advantages of time saving, error checking and control, understanding the overall procedures for water resources management problems through driving the user to the task. 6. The case study provides motivation, ease use, understanding the overall operational flood management works to the system developers as well as terminal users. The results of case study for '1995 flood event in the Han River Basin have provided that the developed methodology and computer based SDSS can operate water surface system to minimize flood impacts at the downstream while maintaining water for next hydrologic period water use during the real-time flood events.