Process Analysis Of The Response Time In The Second Protection Zone Of Headwater Area

Drinking water safety is the major issues affecting the national economy and people’s livelihood and human health, in recent years, as the threaten of drinking water security is increasing, the quality of drinking water descend year by year, the master reason is water quality deterioration. The water quality of drinking water source affects people’s life and health, even survival. Though there is a lot of element which result in water quality deterioration, the prime culprit of water quality deterioration is the water sources without protection and supervision. The effluent and domestic sewage in the upstream discharge into the rivers without reaching the emission standard, the pollution which is transported by the rainfall runoff also can make the drinking water sources losing their value. According to this situation, national environment protection department demand to research the protection of water source, classify the different drinking water source, control the risk of pollution, and protect the quality of drinking water, ensure the safety of drinking water.In order to protect the water source safely and scientifically, the research of the risk water area, the process analysis of pollution transportation and the response time of water is the key link. In this article, the author summarizes the research of home and aboard, aim to research the upper basin of water source and land area in the second protection zone. About the transmission of land area, the author use the water environment kinetic theorv to analysis the structure of water system and the character of water, classify the catchment area, research the path of surface runoff, calculate the catchment time of the runoff, realize the response time of the rainwater runoff. With regard to the water area, the author use a2D finite volume calculate model to analysis the consistency diffusion and conversion process of the pollution, at the end the author research the influence of the pollution which is in the Water quality response area on the water quality of the downstream second protection zone, and also can provide a safe and reliable technical support for the second protection zone.In this article, the author investigates the diffusion and conversion of the pollution in the rainwater runoff of the second headwater protection zone and in the riverway. The research results are as follows:First, Based on the landform. the path of rainfall runoff in the second headwater protection zone is analyzed, the generalized model of the rainwater’s transmission in the second headwater protection zone can be established. Secondly, based on the hydraulic parameters, the author analysis process of the flow concentration in the ditch, and the accumulative time and flow of each tributary which is afflux into the total basin of the different time is calculated. At the end, the process of the pollution’s diffusion and conversion is analyzed by using the water environment kinetic theory, and also the influence of the ditch’s risk input on the quality of the second headwater protection zone is analyzed, and the author provide a method to predict the risk of water quality.