Analysis and Recommendation on Monitoring of Microbial Contamination for Drinking Water in Yantai Port from 2013 to 2016

Objectives To strengthen the sanitary supervision of drinking water and ensure the safety of drinking water for staffs and workers at Yantai port.

Methods Water samples of terminal tap water and from secondary water supplies were monitored for microbial contamination regularly by the Standard Examination Method for Drinking Water.

Results A total of 1 411 samples were examined in 2013-2016, 1 344 of which were qualified with a qualified rate of 95.3% (χ²=39.455, P=0.000 < 0.05). In three of these four years, the qualified rate of terminal tap water on microbiological test was higher than that of water from secondary water supplies, and the qualified rate showed a rising trend. The water quality from secondary water supplies was improved with a qualified rate of 98.5% after water tanks had been rectified and reformed in 2016, which was significantly different from that in 2015 (χ²=30.065, P=0.000 < 0.05).

Conclusions Drinking water was in a good situation in Yantai port on a whole, the maintenance of water tanks had an obvious influence on the microbial contamination of the secondary water supplies, so, targeted management should be carried out on terminal tap water and secondary water supplies to guarantee water quality basically.