A compact portable modular wastewater treatment system which integrates several processing technologies to provide a substantially purified water source. A wastewater stream is sent through an initial filtration step. The filtered wastewater is then subjected to electrocoagulation and then further filtered. The resulting stream containing substantially only organics is then treated in an advanced oxidation process which can include passing an electrical current through the water during the oxidation process. The partially treated water is then passed through ion-exchange columns to polish ammonium and other contaminants. The ion-exchange columns are cycled through regeneration cycles to provide continuous ion-exchange medium. The ammonium rich brine solution used in regeneration is subjected to an ammonium destruct process and then reused in regenerating ion-exchange columns. The water can then be sent through a final disinfection oxidation process to destroy or inactivate pathogens and/or remove any remaining colorants or odor to provide a water source suitable for almost any use.