Research On Rainfall Characteristics And Rainwater Resources In Dalian City

Water is necessary for life, and the foundation for city. Dalian is one of the cities being short of fresh water.With the development of urbanization, the problem of the water is outstanding.On the basis of large sum of articles about relative literatures, a systemically study of annually rainfall data in Dalian from 1905 to 2001, monthly rainfall data from 1951 to 2001 and short duration rainfall data from 2003 to 2005 is put forwards. Surveying several processes of rainfall, using the automatic hydrocone type ombrometer, analyzing the rainfall character in Dalian, drawing the frequency curve, especially, analyzing the time character of the storm, finding the time character of the storm, moreover, and the rainfall pattern is concerned. Advising the relative theory and methods in the mode of rainwater resources, lastly, taking the DUT campus as the example area, putting forward rainwater resources planning for DUT and computing the amount of rainwater and design the reservoir, refined the theory of rainwater resources.According to the analyses of rainfall data, experiments, examples, the main results and conclusions are as follows:(1) The average rainfall in Dalian of multi-year is 607mm, 72.5 percent is from June to September, it is so asymmetric in the year, that the maximum one is 5.4 times as the minimum, so we can conclude the rainfall changes greatly among the year and month.(2) The amount and time of the storm are random in Dalian, the amount of storm is increasing while the rainfall of average year is decreasing. It is usually happened from June to September to a storm, and shows seasonal characteristics. The rainfall pattern of the storm is few symmetrical, most are asymmetric, additionally single peak value one is the main, and others are few. The rainfall pattern whose the peak value is earlier seems more than the later. Storm brings strong rainfall intensity in short duration, moreover, the shorter duration the average rainfall intensity is stronger.(3) The program of rainwater resources is done for DUT campus, calculating rainwater of different kinds of areas, accordingly estimating the demanding storage for flushing in WC, plant, sprinkling and so on, designing the reservoir at last.