This study was conducted to evaluate the removal behaviors of DOM(dissolved organic matter) and
phosphorus in eutrophic lake water by coagulation process with PAC(powdered activated carbon). It was observed
that the removal characteristic of soluble matter was different from that of dissolved one, and the removal of DOM
was effected by both pH and coagulant dosage. It was founded that PAC could increase the removal efficiency by
an adsorption of DOM in coagulation process. A formation of soluble and colloidal matters resulted in the
degradation of phosphorus removal efficiency in a chemical precipitation process. The phosphorus removal efficiency
could be enhanced by an absorption of colloidal matter and dissolved complex with PAC addition. In addition, the
PAC addition caused the increase of floc density in coagulation process, that led to the rise of sedimentation rate,
and resulted in a significant improvement of solid-liquid separation efficiency.