Objective In order to check the hygienic situation of fine drinking water supply in Minhang District and to provide scientific bases for relevent agencies to setting standards for regulation and inspection, this survey was conducted.
Methods Survey on the 23 communities set fine drinking water supply with uniformed form were conducted. Raw water, product water, circulating water and in-house terminal water samples were collected from these communities.
Results Reverse osmosis, nano-filtration and ultra-filtration equipments used to treat water accounted for 4.3%, 65.2% and 30.4%, respectively. All of the communities used ozone to disinfect the fine drinking water, and 69.6% of them used ozone to disinfect pipe systems. The communities all conducted self water quality monitoring, one to four times per month. The value of the COD of the product water was significantly decreased than that of the raw water. The TBC of the in-house terminal water was significantly increased than that of the product water. The design defect in circulating pipe system could lead to the bacteria growth in fine drinking water supply.
Conclusion The quality of the fine drinking water produced is better than that of the general tap water, but it goes worse during transportation. The design defect of the circulating pipe system significantly influences the bacteria growth in the fine drinking water supply.
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