改建深井为主的小型集中供水对淮北农村饮水水质改善效果研究

Assessment of Improvement in Drinking Water Quality since Introduction of Deepwell Tap Water in Huaibei Rural Area

对 3个县共 10个改水村和 12个非改水对照村的分散式给水和以深井为主的小型自来水末梢水定点进行理化指标、微生物的检验和Ames试验 ,结果表明 ,改水前分散式给水细菌总数和总大肠菌群符合“农村实施‘生活饮用水卫生标准’准则”(以下称“准则”)一级标准的合格率只有 10 %和 11 4% ;而改水后提高到 45 %和 70 % ,但微生物超标率仍然偏高。水质卫生指数评价结果分散式给水主要分布在 4～ 6级水 (共占81 6 % ) ;改水后主要分布在 1～ 3级水 (共占 6 0 0 % )。去除微生物的理化水质卫生指数分析结果 ,深井集中供水末梢水5、6级仍占 18 8% ,说明深井集中供水的非微生物的安全性值得重视。Ames试验结果分散式给水均为阳性 ,其强弱顺序为淮河水、朝阳河水 >沟塘水 >浅井水 ,有一深井自来水末梢水亦为阳性 。

During 1996～1998,drinking water quality of noncentralized water supply(NCWS)and tap water from deep well(TWDW)was assessed in terms of physical,chemical,microbiological and toxicological parameters in 10 villages with TWDW and 12 control villages.The results showed that before the improvement,only 10% and 11.4% in total number of bacterial colony and coliform were in keeping with the first grade standard of the “Guideline for Implementation the `Sanitary Standard for Drinking Water'in Rural area” respectively.After introduction of TWDW,this rate rose to 45% and 70% respectively,but the non-qualifying rate still remained too high.The assessment results of the sanitary index of water quality(SIWQ) indicated that altogether 81.6% of water samples met 4～6 grade water quality requirement for NCWS and 60.0% of TWDW samples met 1～3 grade water quality requirement.Judging by physical and chemical indices of the SIWQ(except microbial indices),there were still 18.8% classified as 5～6 grade water,which indicated that the non microbial properties of deep well tap water still merits further much attention.Ames tests for all NCWS were all positive,their decreasing intensity:Huai river water and Caoyang river>pond water>shallow well water.One of the deep weel tap water sample was also positive.In general,the pollution of deep well water through water pipe is of primary sanitation concern.