According to the US Geological Survey (USGS, 2012) water hardness varies widely in the USA and is classified into different categories: soft water (0–60 mg/L CaCO3), moderately hard (60–120 mg/L CaCO3), hard (120–180 mg/L CaCO3) and very hard (more than 180 mg/L CaCO3). A similar high variety has been reported in Korea by the Korea Water Resources Corporation (Water, 2011). These two samples clearly show that there is a high chance of having different properties of the starting water regarding water hardness for the production of SAEW. Authors found only one report on the effects of water hardness on the efficacy of EW (Pangloli and Hung, 2013) while there was no report found on the effects of water hardness on the production of SAEW, its properties and efficacy in inactivating foodborne pathogens.Thus, the objective of this study was to investigate the effects of water hardness on the production of SAEW, its properties and efficacy in inactivating foodborne pathogens. Also, methods for the optimization of SAEW production from inappropriate water sources by the addition of electrolytes were investigated.