Water Balance Model And Its Calculation In Urban Water System

Urban water system is an important infrastructure that built for water resource exploitation, water utility, water and waste water treatment, water distribution, water conservation and flood protection. The challenges are recognized as high population density, economic surge against resource shortage, there is a critical subject of studying about urban water system.By far, economic development, urbanization and climate change have led to an increase imbalance between water requirement and supply, environmental degradation, flooding disaster, etc. Therefore, analyzing the surplus amount within the gap in urban water system is necessary.The thesis aims at building an integrated urban water system model to analysis the alternative methods to solve the imbalance problem, methods refer to explore water resources, reduce consumption, improve the efficiency of distribution, etc. the study is developed as follows,Studies on urban water system model reviewed. Though advanced model had been built and applied largely abroad, even models of mass flow, asset analysis and sustainable assessment is built, integrated water model is still rare in domestic study.With a full understanding of urban water system and water balance theory, models of water system in different levels are developed, which includes indoor, outdoor and networks system. The main study consists of the following aspects,(1) Water balance method and theory are analyzed. Since the components of urban water activities are complex to meet a new water resource requirement, systematic analysis method is presented here.(2) Objectives and their corresponding boundaries of urban water balance are set in model study, where there are three sub-systems named as indoor, outdoor and pipe networks respectively. Within each model, several potential structure projects are suggested for eliminating the imbalance lays in different levels. Then, system units are quantified by employing water balance theory and an integrated system has been built, which would express the system water flow and usage situation in urban area. Additionally, in order to quantify system units, corresponding equations and alternatives are analyzed in sub-system.(3) To release calculation burden of urban water balance model, Excel software is employed as the platform of system model.With a case study, it proved that the model and software developed in this research is useful, and finally, the water problem tackled indicates assessment procedure and some suggestion for improvement is given.The model presented in the paper can be used for integrated urban water system management. Therefore it is worth for urban water system sustainable development.