City's Emergency Water Source Field in North China with the Example of Changchun City

Abstract

Abstract With the shortage of water resources and aggravation of water supply risk in cities, more and more attention has been paid to the problems of emergency water supply. Now, research on emergency water supply already becomes one of the tasks which should be timely resolved. And the way to resolve the problem, choice and demonstration of the water source field are important and profound to cities. As to the cities in north China, they are affected by monsoon climate. As a result, the distribution of precipitation is non-uniform according to time and space. Besides, surface water flows slowly during drought season which results in easy pollution and difficult to treat. Comparing to surface water, the quality of groundwater is better and it is difficult to be polluted. So as to northern cities where groundwater is sufficient, choosing groundwater source field is more significant. First, the concept of emergency water supply is discussed in the paper based on the existing research work. Then the paper divides emergency water supply into two types according to the causing characters. One is emergency water supply caused by sudden disaster and the other is emergency water supply caused by non-sudden event. Accordingly we have two types of emergency water source field. They are sudden emergency water source field and backup water source field. Then the paper analyzes the characteristic of water resources in northern cities when emergency water supply is required, and concludes that it is better to choose groundwater resources as emergency water source field. After that, ten factors which affect the source field are discussed. These factors include the quantity of water, the quality of water, the possibility of drawing, duration of emergency water supply, and safety of the water source field, demanding of water in the source area, environment damage, and economic cost of emergency water supply, artificial regulation and profit balance. Based on it, the paper puts forward both the demonstration objects and demonstration tactics of the cities’ emergency water source field. At last the paper takes a water source field in the middle reaches of Yinma River as an example to demonstrate emergency water source field. The demonstration aims at five affects, including the quantity and quality of water, water drawing methods, environmental influence and economic cost of emergency water supply.