Analysis on Thermotoletant Coliform Bacteria in Source Water of Guangzhou during 2013-2015

Objective To analyze the thermotolerant coliform bacteria index in the source water of municipal and self-built waterworks during 2013-2015 in Guangzhou, and to know the microbial contamination in source water.

Method The data obtained from GZ municipal and self-built waterworks were analyzed by SPSS 18.0 statistically.

Results The average thermotolerant coliform bacteria counts detected from the source water in XJ, BJ, DJ and LXH districts were 1.2×10⁴, 1.7×10⁴, 3.55×10⁴ and 1.4×10⁵/L, respectively, which were all exceeding 1.0×10⁴/L, the standard limit for the grade III of water qualify in the Surface Water Environmental Quality (GB 3838-2002), and the qualified rates were 37.5%, 16.7%, 25% and 0 respectively. The detection rate of thermotolerant coliform bacteria in LXH was higher than that in XJ and BJ districts, and the qualified rate in LXH district was obviously lower than that in XJ district. The detection rate of thermotolerant coliform bacteria in XJ in the third quarter was higher than other quarters of a year. The qualified rate was higher in the first and the fourth quarter of a year.

Conclusions Comparing to other districts, the contamination of thermotolerant coliform bacteria in source water in LHX district was more serious. The detection rate of thermotolerant coliform bacteria in XJ district in the third quarter was higher than that in other quarters of a year. Therefore, we should focus on strengthening water protection and adjusting water disinfection process in accordance with the needs.