Research On Theory And Technical Program Of Rainwater Utilization

The global water crisis is becoming more and more serious. Rainwater is a kind of renewable water resources and has a great potential for utilization. As the most effective way to solve the problem of water shortage、flood disaster and ecological environment, Rainwater utilization has become a hot topic in the whole world in recent years. The utilization of rainwater in China has a long history, which is initially applied in agricultural development and domestic water. The process of urban rainwater utilization in China has lagged behind. But with the accelerated process of urbanization, urban rainwater utilization has been gradually paid attention. The present of “Sponge City” conception in recent years has provided a national support for urban rainwater utilization.This paper investigated theoretical methods in order to guide the practice. Some counter measures and technical methods of urban rainwater utilization are proposed. Taking Xi’an city as an example, based on analysis of the necessity and feasibility of rainwater utilization, the subject put forward some integrated programs of rainwater utilization. The main contents of this subject including:(1)This paper concluded the current status of urban rainwater utilization, then analyzed the impact urbanization on water resources, water environment and water cycles in city and expounds the relationship between urbanization and urban rainwater utilization.(2)Theory and technical programs of urban rainwater utilization system, including rainwater collection and interception, rainwater storage, rainwater infiltration, are studied in detail.(3)Taking Xi’an city as an example, we analyzed the utilization status of water resources and rainfall characteristics in Xi’an, there are many favorable conditions for rainwater utilization, the quantity of the total rainfall in Xi’an is abundant, by calculating, the available rainwater resources can reach 0.588?10 m3~0.82 ?108 m3. Rainwater utilization would alleviate the pressure of water supply in Xi’an City in a large extent.(4)Chang’an University is researched as a model district, rainwater runoff samples are collected to study the runoff quality on different grade road, roof and lawn. On this basis, the quantity of the early abandoned storm water on roof is determined.(5)Three different comprehensive modes of urban rainwater utilization is proposed. Taking Yanta Campus as an example, combining with the building distribution and function, we design a new system of roof rainwater utilization in Yanta Campus.