Analysis of Water Quality Monitoring Data from Secondary Water Supply in Chaoyang District from 2006 to 2009

[Objective]To understand the status of water quality from secondary water supply in Chaoyang district of Shantou city,to provide data for carrying out effective health supervision and guarantee safe drinking water.[Methods]Water samples collected from 53 secondary ware supply units 2 times each year were tested for total amount of bacteria,coli group,turbidity,nitrite including 13 items based on 《Hygienic Specification for Facilities of Secondary Water Supply》(GB 17051-1997) and 《Standard Examination Methods for Drinking Water》(GB/T 5750-2006),and 《Standard of Drinking Water Quality》(GB 5749-2006)and evaluated.[Results]Of the 326 water samples tested from 2006 to 2009,215 of them were up to standard,accounting for 66.0%.The qualified rate was 86.25%,72.62%,57.79% and 41.51% respectively each year,there was a difference(P0.01).The qualified rate of residual chlorine(72.7%),colony counts(74.8%) and coli group(81.3%) was the lowest.There was no difference of the qualified rate of the water from secondary water supply collected in different time and units(P0.05).The qualified rate of water samples collected from municipal secondary water supply was higher(72.8%) than that from other secondary water supply(59.5%),there was a difference(P0.05).[Conclusion]The qualified rate of the water from secondary water supply was lower in Chaoyang district,health supervision must be strengthened,level of professional technological personnel must be improved,in order to improve the quality of secondary supply water.