Implementation Of Urban Drinking Water Quality Monitoring And Evaluation System Based On GIS

Drinking water is the most important condition for safeguarding people’s life. The acceleration of industrialization which is a serious threat to the safety of drinking water, then it is important to strengthen the monitoring and evaluation of water quality of drinking water for ensuring drinking water safety.Until the development of evaluation of water environment in our country, the evaluation of water environment quality has almost become an indispensable part in comprehensive environmental quality evaluation. With the rise of GIS, its related theories have also been applied to monitoring and evaluation of water quality. We can use GIS with its characteristic, such as spatial analysis, dynamic connections between the spatial data and attribute data, which is easy to transform a mount of attribute data into spatial data and to update. GIS makes date more intuitive and convenient, accurate, and timely. Establishing the monitoring and evaluation system of water quality based on GIS was a trend of informatization in water environmental science.Firstly, the paper introduces the study background and significance, as well as the domestic and international research dynamic status in combining GIS with water environment models. Secondly, describes the basic situation of water quality of urban drinking water source in China, the evaluation criteria of drinking water quality and three kinds of water quality assessment methods that are single-factor evaluation method, comprehensive index evaluation method, comprehensive nutrition state index. Thirdly, studies on key technologies, such as Web-GIS, Flex, Web Service, Oracle. Then starting with this work, we establish a monitoring and evaluation system based on GIS for urban drinking water quality that combines with the assessment model and orients to the professionals and the public. Since confirmed the objectives of the system, we do some designs of general structures, main functions, database and interface. Finally, accomplish the monitoring and evaluation system that relied on the development platforms which are ArcGIS, Server10.0, Flex4.6, Visual Studio2010and OraclelOg. A map service features is provided by the system, including map, basic geographic information query. System gives three query methods, includes monitor data queries, compare query, queries for time series. It presented the monitor data to users in diversify. Water quality assessment was carried out in three methods that are single-factor evaluation method, comprehensive index evaluation method, comprehensive nutrition state index. Then thematic maps which intuitively show the grade distribution were drawn up. In the end, statistical analysis features is provides for the evaluate results and factors of monitoring.System realizes dynamic monitoring of the water areas and related lands that supply drinking water to the city, reflects the changes of water chemical composition and resource in water areas at the level of space and time series systematically. It evaluates the quality of water bodies according to Water Quality Assessment Model scientifically, and uses the statistical functions completely present water quality within a period. The system is a tool for the information management of water source and the technical support which ensure safety of urban drinking water.