Study On Water Quality Evaluation,Current Situation And Sustainable Development Of Rural Water Supply In A District Of North China

Safe and reliable drinking water is closely related to the health and living standards of rural people,and is an important part of the strategic plan for rural revitalization.The evaluation of rural drinking water quality and the construction of water supply projects in a certain district of North China are of great significance to the stability of the local society,the improvement of people’s living standards,and the integrated development of urban and rural areas.This paper investigates a rural water supply project in a district of North China plain.Compared with the evaluation methods of drinking water quality,the pollution indicators obtained that shows the drinking water need to be dealt with urgently.According to an analysis of the problems existing in the area’s drinking water safety,water supply management and service processes.The sustainable development of water supply projects was discussed in three perspectives,water supply safety,management and service.And the corresponding reasonable suggestions for existing problems were put forward.In the evaluation of drinking water quality,both the national standard and the water quality index（WQI）of drinking water quality are based on the"Standards for Drinking Water Quality"（GB5749-2006）to evaluate the drinking water quality qualitatively and quantitatively.Health risk assessment is a water quality assessment method,which links pollutant exposure with human health and assesses the impact of pollutants to human health.Through the application of three methods,the rural drinking water quality in a district of North China plain was evaluated and the water quality was compared from different dimensions to improve the feasible water quality assessment method.The national standard and WQI assessment results show that the qualified rates of water samples are 51.4%and 89.2%,respectively.Compared with the national standard method,WQI has greater advantages in explaining the risk value of regional drinking water and judging whether the water quality is suitable for drinking.Comparing the first two methods,the health risk assessment is not affected by the national standard limit,and can point out the potential health risks of the indicators below the limit.The evaluation results show that As and hexavalent chromium are the main pollutants,of which the concentration of Cr⁶⁺is lower than the standard limit,and the non-carcinogenic risk and carcinogenic risk of both exceed 10^-6.The total non-carcinogenic and carcinogenic risks of pollutants to children are 10 times and 2 times that of adults,respectively.Compared with the national standard method and WQI,the health risk assessment is not affected by the limit of national standard value,and the potential health risks of the indexes can be obtained.The joint applications of WQI and health risk assessment in drinking water quality assessment not only covers the important indicators of the"Sanitary Standards for Drinking Water"（GB5749-2006）,but also conducts the exposure assessment of drinking water intake for the non-carcinogenic and carcinogenic indicators with greater hazards,and could show the pros and cons of water quality quantitatively,comprehensively and objectively.And it is clear that the main pollutants in drinking water in this area are total coliforms,As and Cr⁶⁺.In terms of the operation and maintenance of rural water supply,the main problems are as follows.Firstly,6%of the water supply stations lack water source protection measures,14%of the station areas have poor environment and hidden safety trouble in drinking water.Secondly,8%of the water supply facilities of the water supply stations failed to operate and maintain in time,resulting in partial water quality unqualified.Thirdly,general implementation of the water supply project management system,and lack of professional management personnel,and up to85%of the water supply stations that fail to publicize as required.Fourthly,production safety inspection supervision is weak,about 10%of the water supply station inspection records and files are incomplete.Fifthly,only 30%of have home meter installed,and difficulty in collecting water charges.There are two main reasons for the above-mentioned problems.On the one hand,villagers lack awareness of drinking water safety protection,and the implementation of policies by relevant departments is not in place.On the other hand,the management mode of water supply projects and water supply services are backward.Based on the investigation and analysis of the quality,operation and maintenance of rural water supply,the following suggestions are made for the sustainable development of rural water supply projects.（1）In terms of water supply safety,the villagers’awareness of drinking water safety protection should be raised.The government and relevant departments should take the overall management role to form a water supply safety management model with“government guidance and supervision first,and public participation and supervision supplemented”to strengthen the protection and management of drinking water sources and the water supply environment as well.Increase the water supply facilities such as nan filtration membrane treatment equipment to improve the water quality of exceeding heavy metals standard and ensure the safety of water supply.（2）In terms of water supply management,water supply projects with tens of thousands of tons and tens of thousands of people should implement corporate operation and professional management,and water supply projects with less than thousands of people should take the small-scale project commission management model as the prototype and entrust professional organizations to assist in management.Regularly carry out professional training for management personnel,and organize functional assessment and exchange activities.Strengthen the fire management and water quality monitoring of water supply stations,build a sanitation supervision system,conduct safety production inspections,and flexibly partition.（3）In terms of water supply services,such measures should be made:government and managers should clarify the role and function allocation of the water supply service process,and realize the transition from hardware delivery of water supply engineering to service delivery.Increase the villagers’awareness of water fee collection,optimize the metering facilities,use modern means to pay fees,and implement guarantee mechanisms such as water price subsidies and operating management costs.Make full use of the Internet of Things,big data and cloud computing to build an informative,intelligent and automated control and management system,promote water data integration and sharing,and create a rural smart water service system.