Recently, constructed wetlands are consistently applied to the dam or artificial lake for the purpose of pollutants removal. Constructed wetlands is one of the good measures to treat non-point pollutants of dam inflow. In this study, the characteristics and design considerations of constructed wetlands are discussed. Actual constructed wetlands in domestics and overseas are also introduced and discussed in this study. Most constructed wetlands in domestic are consist of reservoir, settling area, planting area and final sedimentation basin. In spite of the main objective of constructed wetlands is to treat non-point pollutants. Pollutants removal is not significant at the most domestic constructed wetlands, whereas restoring of natural ecosystem is more active. Otherwise, wetlands of other countries were constructed for the direction of natural wetland restoring. Sand and clay from the flood is settled and rural wastewater is treated by passing through this restored wetlands.
Pollutants removal rate is not a good evaluation factor of constructed wetlands and a new evaluation factors like biodiversity should be developed. Long term monitoring and maintenance is also essential to success the constructed wetlands.