The availability of high-quality potable water is essential in crewed space missions. Closed loop water recycling systems as well as potable water holding tanks and waterlines provide environments for biofilm formation that can facilitate the growth of human pathogens, as well as organisms that can cause deterioration of distribution lines. Prevention requires the maintenance of a chemically stable and biologically effective residual concentration of biocide in water and wetted surfaces of the system. Current disinfection technologies in potable water systems for space applications utilize either iodine or silver biocide. Limitations exist in terms of incompatibility with some disinfection chemistries and surfaces, long-term health risk, rapid biocide depletion, and need for consumable supply and waste disposal. Lynntech proposes to develop an advanced disinfection system for water disinfection and biofilm prevention based on an on-demand biocide generator which does not require consumable chemicals. Excess disinfectant is decomposed on-demand into water and oxygen, representing zero toxicity for crew consumption of potable water. During the Phase I project, the effectiveness of the proposed system for potable water production will be demonstrated. During the Phase II project, an automated system will be developed and delivered to NASA.