Testing for bacteria in water is done based on intended purposes, such as drinking, producing ice, utilizing it in the house, producing water taps, and processing water. Bacterial growth and survival in water are influenced by environmental factors, which may have consequences for human health. The purpose of this study was to identify factors influencing the failing standard of water quality for consumption. Water quality data from the annual report of Regional Medical Sciences Center and meteorological data from the National Statistical Office of Thailand were obtained for the fiscal years 2002-2021. A logistic regression model was used to identify factors associated with the failing standard of water quality for consumption. The findings revealed that 16.6% of the total sample did not meet the consumption standard, with Public Health Area (PHA) 11 and 12, failing at rates of 49.6% and 38.3%, respectively. Overall, water produced in PHA 11 was statistically (p-value < 0.05) substantially associated with bacterial contamination, which increased with production year, air temperature, and precipitation. In conclusion, environmental factors and other water quality were influential on biological water quality in Southern Thailand. Therefore, necessary measures must be taken to improve water quality standards in this area to safeguard the protection of consumers.