Analysis of water quality improvement efficiency using constructed wetland in a coastal reservoir

Analysis of water quality improvement efficiency using constructed wetland in a coastal reservoir

Diverse and comprehensive countermeasures were established to prevent water pollution in coastal areas such as constructed wetlands(CW).This study was conducted to assess the water quality improvement through CW constructed along the shoreline of Hwaseong coastal reservoir. The CW is located in Hwaseong-si, Gyeonggi-do and consisted of a forebay and a wetland. The CW was monitored twice during rainy days and 10 times during dry days. The monitoring results indicated that in and out flowrates were highly correlated with COD and TN loads. COD, TN and TP concentrations in the forebay was lower during dry days than rainy days. However, concentration and mass removal efficiencies of COD, TN and TP were greater during rainy days. In addition, the volume flowing into the CW was less compared to the outflow during rainy days indicating that the CW efficiently reduced the runoff volume. The overall pollutant removal efficiency of the CW were at least 50% for TSS, 20 to 35% for TP, and 26 to 94% for TN. The data gathered may be used to improve the pollutant removal efficiency of the system in the future.