Study On Water Quality And Safety Protection Of Drinking Water Source Moertan Reservoir Based On GIS

Water is one of the factors that people depend on for existence. Drinking water source pollution is one of the most serious and universal drinking water problems in our country in recent years. It directly affects all aspects of people's life and social production. Chengdu has proposed the establishment of Moertan Reservoir as a reserve water source for drinking water,so as to avoid the danger of drinking water safety and water shortage. Moertan Reservoir drinking water source water has more complex structure, the basin boundary is difficult to define, pollutants are discrete and the historical hydrological information and monitoring data are lacking, the weak foundation of research problems for water security presents a major challenge. At the same time, "13th Five-Year-plan" environmental protection plan to implement grid,differentiation, fine management requirements, to ensure quality and safety. Therefore,how to realize the accurate definition and fine prevention and control of the water quality response area, and the identification and effective prevention and control of pollutant output, so as to ensure the water quality safety in the reservoir area, become a realistic problem that needs to be studied. But the current grinding hydrogeological data and historical data, reservoir research foundation is weak, and lack of research on drinking water quality and safety control of the fine lack of support of theory and methods, scientific research system and effective prevention and control program is not formed.Based on GIS and remote sensing technology, combined with field investigation and research,this paper makes a precise study on the composition of water quality response area and pollutant output in this area, and makes a quantitative analysis. The main tasks are as follows: ?The multi scale research, prevention and control and decision making technical system of "basin--water quality response area--water quality response unit" was constructed by using GIS. ?A generalized model of pollutant transport in the water quality response area is established. And the use of IWHR rational formula analytical models of different frequency(P). Quantitative analysis of water quality response unit and pollutant transport path is carried out, and pollutant transport time response unit diagram and equal flow time map are obtained.?Based on the remote sensing images and field exploration of reservoir water quality response to land types in the region are classified, and corresponding types of pollutants, output coefficient, calculate the single quality response to the pollutant output unit and the total area of the water quality response contribution rate, and targeted reduction potential research, so that water quality and safety risk control unit classification and visualization. ?Conclusion the study time, traffic and pollution contribution rate and reduction potential, the pollutant transport path and water quality response unit grading comprehensive prevention and control system, and visualization for grinding beach reservoir comprehensive prevention and control of water quality and safety unit plan, to guide the practical work. ?Based on multi-scale water quality control, prevention and control plan is formulated.Besides, the paper came to conclusion as below:(1) Based on the response time factor, the water quality response unit A27(beach slope of right bank of Moertan Reservoir dam) belongs to the water quality express area, It is necessary to focus on prevention and control and take necessary engineering measures to control it. The water quality response units A21, A22 and A23(The three response unit areas are close to the right bank of the reservoir, And the A21 and A22 are the last two response units of the 2# gully into the storage area, A23 is the last response unit for the 1# gully to enter the reservoir area.) belong to the rapid response area of water quality, and the key monitoring should be carried out, and proper engineering measures should be taken to control them.(2) Based on the flow control research, the important nodes of the pollutant transport path are d, g, i, j, k, R1 and R2, which need to be monitored with emphasis,and appropriate measures should be taken to control if necessary.(3) Based on the contribution rate of pollutant output and the reduction potential,the key prevention and control units are A27 and A22. A27 water quality response unit for water quality response area pollutant output contribution rate all in the top 10, and the average is 39.65%, the highest contribution rate project TP reached 78.2%, need to be regarded as the key, prevention and control area priority to project control. When the reduction of 50% is made, the effect of unit reduction and total reduction is obvious, so the A27 unit, especially the pig farm, the community and the cultivated land, should respond to the engineering protection. The 7 indicators of A22 water quality response unit are ranked 10 before the contribution rate, and the reduction potential is higher than the other unit areas,and the main pollution source is the community, so it is also listed as the key prevention and control area.(4) The conclusion of the study of visual frequency value under the different flow response Mo Er reservoir water quality and safety prevention and control plan comprehensive classification unit map, contour map and time, flow rate and contribution rate and reduction potential and other factors, the comprehensive classification focus on prevention and control unit for A27, A22, A21, A23.