Lehtola Markku J, Nissinen Tarja K, Miettinen Ilkka T, Martikainen Pertti J, Vartiainen Terttu
Laboratory of Environmental Microbiology, National Public Health Institute, P.O. Box 95, Kuopio 70701, Finland.
Water Res. 2004 Feb;38(3):601-10. doi: 10.1016/j.watres.2003.10.054.
Deterioration in drinking water quality in distribution networks represents a problem in drinking water distribution. These can be an increase in microbial numbers, an elevated concentration of iron or increased turbidity, all of which affect taste, odor and color in the drinking water. We studied if pipe cleaning would improve the drinking water quality in pipelines. Cleaning was arranged by flushing the pipes with compressed air and water. The numbers of bacteria and the concentrations of iron and turbidity in drinking water were highest at 9 p.m., when the water consumption was highest. Soft deposits inside the pipeline were occasionally released to bulk water, increasing the concentrations of iron, bacteria, microbially available organic carbon and phosphorus in drinking water. The cleaning of the pipeline decreased the diurnal variation in drinking water quality. With respect to iron, only short-term positive effects were obtained. However, removing of the nutrient-rich soft deposits did decrease the microbial growth in the distribution system during summer when there were favorable warm temperatures for microbial growth. No Norwalk-like viruses or coliform bacteria were detected in the soft deposits, in contrast to the high numbers of heterotrophic bacteria.
配水管网中饮用水水质的恶化是饮用水配送中的一个问题。这些问题可能包括微生物数量增加、铁浓度升高或浊度增加，所有这些都会影响饮用水的味道、气味和颜色。我们研究了管道清洗是否会改善管道中的饮用水水质。清洗是通过用压缩空气和水冲洗管道来安排的。晚上9点，当用水量最高时，饮用水中的细菌数量、铁浓度和浊度最高。管道内的软沉积物偶尔会释放到大量水中，增加饮用水中铁、细菌、微生物可利用有机碳和磷的浓度。管道清洗减少了饮用水水质的日变化。就铁而言，只获得了短期的积极效果。然而，在夏季，当有有利于微生物生长的温暖温度时，去除富含营养的软沉积物确实减少了配送系统中的微生物生长。与大量的异养细菌相比，在软沉积物中未检测到诺如病毒或大肠菌群。
