四川省某县农村分散式供水水质监测结果分析

Analysis of water quality monitoring results of decentralized water supply in rural areas in a county of Sichuan province

目的掌握四川省某县分散式供水水质状况,为制定该县农村饮水安全策略提供依据。方法2015~2019年,以某县47个社区和185个行政自然村为抽样框,对水务部门提供的810个农村水质检测点进行监测。结果共检测水样1049件,总合格率为14.4%。5年水样合格率以及为农户用水的分散式供水水样合格率差异有统计学意义(Р<0.05);2015~2016年,学校分散式供水合格率(69.0%)高于农户分散式供水合格率(13.2%);不同水期合格率差异无统计学意义(Р>0.05);由于微生物指标不合格导致的不合格水样在总体不合格水样中占96.1%(863/898);硝酸盐、肉眼可见物、总硬度、浊度、耗氧量、锰、铁、臭和味等指标存在超标情况。结论目前该县分散式供水水质较差,微生物污染是首要因素,毒理学指标、感官性状和一般化学指标超标并存,存在健康隐患,急需进行针对性治理。

Objective To master the water quality condition of decentralized water supply in a county of Sichuan province,and provide a basis for the development of strategies for drinking-water safety in rural areas of this county.Methods From 2015 to 2019,a total of 47 communities and 185 administrative and natural villages in the county were selected as the sampling frame,and 810 water quality monitoring points in rural areas provided by the water utilities department were monitored.Results A total of 1049 water samples were tested,and the total pass rate was 14.4%.From 2015 to 2019,the difference between the pass rate of the water sample and that of the water sample of the decentralized water supply used for peasant households was statistically significant(P<0.05).From 2015 to 2016,the pass rate of the decentralized water supply used for schools(69.0%)was higher than that used for peasant households(13.2%).There was no statistically significant difference in the pass rate between different water phases(P>0.05).The unqualified water samples due to unqualified microbial indicators accounted for 96.1%(863/898)of the overall unqualified water samples.Indicators such as nitrate,visible matters,total hardness,turbidity,oxygen consumption,manganese,iron,odor and taste exceeded the acceptable levels.Conclusion At present,the county has a poor water quality in the decentralized water supply,and microbial pollution constitutes the primary factor.Targeted governance is in urgent need as health risks exist due to the toxicological indices,sensory properties,and general chemical indices exceeding the acceptable levels.