Sanitary monitoring of drinking water in rural areas of Dalian city 2011

Objective To investigate the health situation of village concentrated water supply,provide scientific basis for improving rural drinking water hygiene and protection of drinking water safety in rural areas.Methods From March to August in 2011,two hundred and fifty concentrated water supply sites were selected randomly in villages,and their basic situation was investigated.The source and peripheral water of each site was detected.Results The decentralized water supply was major source of the water supply in Dalian,and ground water was major source of countryside concentrated supply water,the proportion of complete treated engineering water was 2.09%.In the 1 000 detected water samples,in the case of no sterilization,the total qualification rate was 73.80%,the total qualified rates of drought period and wet season were 80.80% and 66.80%;The qualification rates of source and peripheral water were 75.00% and 72.60%.The microbes and nitrate exceeded national standard obviously,and coli group,the total number of colony,nitrogen and heat proof coli group also exceeded standards obviously,which qualified rates were 93.20%,91.40%,83.70% and 75.00%,respectively.Conclusion The water disinfection facilities of rural central water supply project is not perfect in Dalian,low qualified rate of water,microbial indicators and nitrate exceeding the national standard is high so that safety of drinking water has some hidden troubles.