Research On Rainwater Utilization In Handan

Water is an irreplaceable resource for the survival and development of human. With the rapid development of urbanization and industrialization, problems such as conflict of water supply and demand, prevention and cure of water environment pollution and flood control and drainage in city, were increasingly standing out. Many cities around the world are encountering shortage of water resources and water pollution. Rainwater is a precious water resource, which plays a crucial role in replenishing surface water resources and protecting the ecological environment. So the utilization of rainwater is a main approach to achieve sustainable use of water resources.The primary purpose of this paper is to study the utilization of urban rainwater and the improvement of urban water environmental system. On the base of the present research introduction of urban rainwater utilization, it was analyzed that the influence of urbanization on water source, water environmental system and water circulation, and the necessity and feasibility of utilization of urban rainwater were studied. After the ways of utilization were classified, the approaches to rainwater utilization were discussed. The utilization theory of urban rainwater was analyzed. The basic mode and procedure of the utilization of urban rainwater were established and discussed. At last, the measures of the utilization of urban rainwater were suggusted.On the specific application study, the paper makes a systematic analysis of utilization of rainwater in a campus and surrounding areas. It was monitored the runoff quality on the diverse roof and different road surfaces. The main study results obtained are as follows:(1) By analyzing rainfall of Handan city, it could be known that the average annual rainfall of Handan city during the past 45 years was 558.8 mm, in which the maximum rainfall was 1034.99 mm in 1963 and the minimum rainfall was 313.93 mm in 1986, showing that the maximum rainfall was more than three times of the minimum rainfall. The major rainfall was focused between June and September, during which the rainfall was 74.26% of the whole year rainfall,revealing that the annual variation of rainfall was big.(2) It was analyzed that the quality of rainwater runoff and the rules changing from 2007 to 2008 in Handan, and summarized the rules of rainwater runoff quality varying with the factors such as rainfall intensity, duration time of rainfall, the season, climate and so on. It was found that pollutants concentration was higher at the beginning of rainfall, and the concentration of pollutants tended to a constant value with the increase of rainfall strength and rainfall duration.(3) Base on the analysis of rainwater quality, it was studied that the relationship between pollutants of rainwater runoff using the method of linear regression, and provided the process of rainwater treatment for roof, roadway and lawn.(4) The measures were suggested for the control of campus rainwater pollution, and utilization of campus rainwater was analyzed.(5) The benefit of rainwater utilization in Handan was evaluated by the fuzzy comprehensive appraisal method.The result of evaluation of the benefit of rainwater utilization showed that, it is feasible on technology and economy, which will bring considerable benefits to economy, society and environment, alleviating the shortage of water resources and improving urban environment in Handan.