Application Research Of Water Quality Risk Index System And Evaluation Models Of Rural Centralized Water Supply

Due to restricting factors such as design, construction, operation management and technical advancement, the health management of rural centralized water supply facilities in China is not high, resulting in low level of qualified drinking water supply and potential risks of water safety at different degree. Since the construction of the rural centralized water supply projects in China, there is neither a working concerning risk assessment of rural centralized water supply water quality, nor a perfect risk index system and evaluation model as well. Thus it is of great significance to build a water quality risk index system and evaluation models responding to the characteristics of the rural centralized water supply to protect of rural drinking water safety.ObjectivesTo develop a risk index system for rural centralized water supply and determine the weight coefficient of each water quality risk indicators, to analysis application effectiveness of commonly-used evaluation methods in rural centralized water supply water quality risk.Methods(1) To develop a risk index system and the corresponding weights of rural centralized water supply water quality by Delphi method and fuzzy analytic hierarchy process; (2) To evaluate and sort water quality risk of13rural centralized water supply projects by use of AHP, AHP-TOPSIS and WRSR methods, and to checkout the results consistency of the three methods by Kendall concordance coefficient.Results(1) Having established risk index system of water quality for rural centralized water supply and the weight of each indicator, including source water sanitation, design and operation of water treatment facilities, water plant internal management, design and operation of water distribution network and regulating structure, totaling19indicators.(2) Using risk index system in the pilot plants water quality for risk assessment, the evaluation results of AHP, AHP-TOPSIS and WRSR methods for13waterworks have the same sorting order, and their consistency check result was0.98839, P<0.05.(3) The Kendall concordance coefficient of risk assessment sorting results for the three kinds of evaluation methods and risk index system of the rural centralized water supply water quality in pilot plant evaluation are in consistent with index system of literature whose consistency check result is0.91331, P<0.05, water quality risk results of rural centralized water supply have higher reliability.Conclusions(1) The risk index system of the rural centralized water supply established through the Delphi methods reflect important elements of China’s rural centralized water supply water quality risk more accurately.(2) Using FAHP to calculate rural centralized water supply water quality risk weights of various indicators are accurate and credible, and they have same link degree of influence of China’s rural centralized water supply water quality risks.(3) AHP,AHP-TOPSIS and WRSR can be applied to the rural centralized water supply water quality risk assessment work, the sorting result should support each other, and combining the actual situation in specific judgments.