Disease transmission via the aquatic route, including recreational water, drinking water, and seafood from polluted water, has been and continues to be a problem. The primary objective of the research study reported herein is to evaluate the feasibility of ozone for disinfection under stringent bacteriological standards that may be required for wastewater discharges in or near shellfish waters. The factors influencing ozone disinfection to high levels along with high level disinfection data obtained from full-scale pilot facilities are discussed.