Implementation of Geographical Information System for Bacteriological Contamination Analysis on Refill Drinking Water Depot (Study in Tembalang District)

People used refilled-drinking-water for household and food stall because its efficient and low cost. Based on Indonesian Health Ministry regulation, it should not have any coliform bacteria. This study aimed to describe the bacteriological contamination of refilled drinking water using geographical information system (GIS). In this research, it was used an analytic observational method. The samples were from all available (37) depots in Tembalang district, one form each depot took used a sterile bottle. Contamination of bacteria was identified by Most Probable Number (MPN) method lactose broth media, Mac Conkey media, and IMVIC media. The depot samples were then plotted on (GIS). This study showed 95% samples were not feasible to consume since they contamined coliform. All sub-district had one that contaminated by coliform, 75% sub-districts had depots that contaminated Escherichia coli, while 55% sub-districts had depots that contaminated with other bacteria. The internal risk factors of the contamination were the absence of hygiene-sanitation worthy certificate (95%), depots location near to pollution sources (5%), and the misused of UV light. The external risk factor was lack of quality control that was not as the sterilization from office health Semarang city. Policy reinforcement should be done to all of the depots