Microbial indexes of drinking water in areas under rural drinking water safety project in Quanzhou municipality of Fujian province

Objective To examine microbial indexes of drinking water from rural water works covered by drinking water safety project in Quanzhou municipality of Fujian province.Methods A total of 2 484 samples of finished and tap water supplied by 621 rural drinking water works in 5 counties of Quanzhou municipality were collected with stratified random sampling during wet and dry seasons from 2010 to 2014 and detected for microbial indexes.Results The overall qualified rate of the microbial indexes for the samples was 60.14% and the annual qualified rates ranged between 54.58% and 64.86%.The microbial index qualified rate for finished water samples from the centralized water works was significantly higher than that from the small-scale centralized water works (70.83% vs.59.26%,χ²=11.3;P=0.000 8);for the samples from the small-scale centralized water works,the microbial index qualified rate of finished water was significantly higher than that of the tap water (61.20% vs.57.05%,χ²=4.03;P=0.045).There was a significant difference in the microbial index qualified rate between the finished water samples from water works using unfully treated surface water and underground water (43.10% vs.60.23%,χ²=12.87;P=0.0003).The overall microbial index qualified rate was significantly different among the water samples from the water works using chlorinated lime (54.62%),liquid chlorine (86.27%),and chlorine dioxide (81.82%) (χ²=65.09,P<0.05);no significant difference in the qualified rate was observed for the water samples from the water works using fully treated,precipitated and filtrated,and unfully treated underground water (P>0.05).Conclusion The qualified rate of the microbial indexes of drinking water from rural water works in Quanzhou municipality of Fujian province is relatively low.