The GIS-based Regional Planning Of Rural Drinking Water Supply

The unsafe drinking water is one of the major problems in rural China. More than half of the people who drink unsafe water must drink safe water by 2015. And the problem of drinking unsafe water must be basically solved in rural areas by 2020. Therefore, it is very important for local governments to plan and construct rural drinking water projects. There are many problems, however, in traditional project planning of drinking water, such as long cycle and difficult optimization. This paper attempts to introduce GIS technology in order to study chief methods and key technologies of regional planning on rural drinking water projects.Based on some correlative theories and practices, we choose a case of Zhenping County, Henan Province, and assess safe status of drinking water, medium and long-term demand as well as distribution of water resources. At last, we put forward project scheme of rural drinking water in support of GIS. In detail, in order to plan projects of rural drinking water, in the first place, a database is established, and the spatial safe status is analyzed about rural drinking water. In the second place, the predictive model is synthetically introduced for rural water consumption, and the best types and best locations of wellheads are planned. In the end, pipe network design is optimized in order to identify the optimal project number, the best project location, the optimal project capacity and the optimal network path as well as the optimal pipe diameter. In this paper, anyway, data management, cartography and modeling are implemented in support of the software ArcGIS 9.0.It is found that there are many spatial differences in drinking water safety, water consumption and water supply gaps as well as wellhead status in rural Zhenping County. TPMGPC (totality of population machinery growth per capita) is highest in the plain region, higher in the hilly region, and lowest in the mountainous region. On the contrary, TSLPC (totality of standard livestock per capita) is highest in the mountainous region and lowest in the plain region. According to predictive water consumption and water gaps, 23 key villages are identified for regional drinking water planning. It is also found that optimum wellheads are better selected using the theory of MEMV (maximum-effect measuring value), that optimal pipe network is designed and its diagram is made automatically and efficiently using SPGA (Single Parent Genetic Algorithm).It is indicated that GIS technology has played an important role in regional planning of rural drinking water. GIS can not only meet the needs of safe evaluation and thematic mapping as well as spatial analysis on rural drinking water, but also dynamically query water consumption in different villages and different planning period. It is also showed that GIS can objectively reflect the spatial difference in both predictive water consumption and water gaps. GIS can plan no-facility regions, spring-quoted regions and wellhead-centralized regions as well as wellhead-decentralized regions according to local conditions. In particular, GIS has great potential in regional planning of rural drinking water if GIS is connected with network calculation theory and system optimization theory.