A method and apparatus for using a combination of sonication and ozone to decontaminate pressurized water. The process includes pumping water from a source, such as a creek, river, pond or the like. The water is strained and filtered, and then transferred to a treatment container where it is pressurized for treatment with ozone and ultrasound. The treated water is then piped to a storage tank for subsequent use. The uninterrupted sequential transfer of water from the source, through a treatment container and to the storage tank is accomplished automatically by way of electronic sensors, valves and pumps that are made to communicate with a central processor control unit.