Sanitary Analysis on Urban Drinking Water Quality in Lanzhou in 2017

Objectives To understand the sanitary situation of urban drinking water quality in Lanzhou.

Methods 84 drinking water monitoring sites were selected randomly and 168 water samples were collected and analyzed in Lanzhou in 2017.

Results The qualified rate of 168 water samples was 78.0%. The qualified rate of groundwater (56.3%) was lower than that of surface water (83.1%), (χ²=10.865, P < 0.05). There was no significant difference between the qualified rate of wet season and dry season, and there was also no significant difference among the qualified rate of source water, finished water, and terminal piped water. The range of qualified rate of 33 detection indexes were from 91.7% to 100.0%, of which turbidity was the lowest. The qualified rate of nitrate nitrogen, chloride, sulfate, total dissolved solids, and total hardness of groundwater were 87.5%, 93.8%, 87.5%, 81.3%, and 65.6%, respectively; which were lower than that of surface water (100.0%), (χ²=12.452, 4.110, 12.452, 21.280, 44.565, P < 0.05).

Conclusions The quality of urban drinking water in Lanzhou is generally good. Sensory properties and general chemical indexes are important factors affecting the water quality.