A dissolved air flotation system and method for purifying fresh water. The system is self-contained within a standard shipping container, with all components disposed in-line within the shipping container. Float is removed from the flotation tank with a skimmer that drives float downstream onto a conveyor belt, and the conveyor belt conveys float away from the flotation tank, in the downstream direction, and deposits the float in a collection tank. Clean water may be drawn from the flotation tank continuously, while float may be removed periodically.