The objective of this study was to establish a comprehensive water monitoring strategy to obtain convincing data on the microbial quality of Honolulu Board of Water Supply (HBWS) groundwater sources and water in the potable distribution sytem for the purpose of determining whether the groundwater sources are contaminated with fecal matter. A comprehensive monitoring program 7 was devised based on analyzing larger water samples (up to 1,000 ml) and analyzing for multiple fecal bacterial indicators (total coliform, fecal coliform, E. coli, fecal streptococci, C. perfringens), other bacteria (total heterotrophic bacteria, hydrogen sulfide producing bacteria), as well as coliphages. The results of this study show that the potable water sources had very low levels of fecal indicator bacteria. Most of this low level of contamination was due to total coliform bacteria, a bacteria which has many non-fecal sources. Based on all the available data, it was concluded that HBWS groundwater sources are not vulnerable to contamination with fecal matter. Includes 24 references, tables.