Development Of Green Drinking-water Source (Reservoir Type) Assessment Method

Nowadays, the safety of drinking-water has become one of the most concerned issues all over the world. According to many studies, the quality of drinking water is directly related to public health and sustainable development of society. Due to pollution of drinking water sources, China is facing serious issues of drinking water security, and protection of drinking water sources has become a priority of the government and the public interest. Scientific and reasonable assessment of the water sources is prerequisite for the protection. Now, assessments of drinking-water source in China are based on water quality and quantity. Because of many reasons, deficiency and hysteresis are unavoidable in the update of water quality standard. Therefore, the existing assessment methods need to be improved.Current environmental situation, there is an urgent requirement to systematically establish assessment methods and standards of drinking water sources, which are based on source and process control. This study takes "green" water source assessment as the proposition, aims to build "green" water source assessment method, and provides theoretical support to the "green" certification of water source assessments in Zhejiang Province. Reservoir drinking-water source which has simpler hydrological characteristic and less influence of human activities than rivers and lakes is selected as the object of this exploratory work.Based on the analysis and summary of previous theoretical researches and practical experiences, the assessment method of water sources which consists of eco-environmental status assessment and environmental risk assessment has been established as following:1. A comprehensive and systematic assessment framework has been built. Vertically, the environmental conditions for status and environmental risk assessments for future trends are selected and put to use; horizontally, the risk to the safety of water quality is identified in each process of water cycle including precipitation and accumulation, every pollution source to each risk and eco-environmental factors of water source are analyzed to guide the building of indicators. The vertical and horizontal integration makes sure the indicators of assessment method are comprehensive and systematic. 2. A hazardous rating list of pollution sources which is suitable for survey of pollution sources in China is compiled, based on the hazard classification of pollution sources from California, USA, combined with our widely used industry classification for survey of pollution sources, considering the characteristics of pollution sources and referring to the National List of Hazardous Wastes and Hazardous Waste Identification Standard. This list is clear and practical to use in hazardous rating of pollution sources.This thesis selected three reservoir-type water sources in Zhejiang Province (hill-stream valley, hill-river and plain-stream valley) as the objects of case applications, took the year of 2008 as the assessment period and accomplished "green" water source assessments. Based on actual situations of three reservoirs and contrast of assessment values between the reservoirs, we can infer that, this "green" water source assessment method is practical, comprehensive and reasonable. Meanwhile, the assessment results also provide important information to water source protection and management.