Study on Domestic Wastewater Treatment of the Horizontal Subsurface Flow Wetlands (HSSF-CWs) Using Brachiaria mutica

This study aimed to evaluate the effect of domestic wastewater treatment on the horizontal subsurface flow-constructed wetlands (HSSF-CWs) using Brachiaria mutica vegetation. We used two wetland models: one with plants and the other without plants. These models were built according to the following dimensions (L × W × H = 1.2 × 0.4 × 0.8 m) and operated at four organic loads (30, 60, 90, 120 kg COD/ha.day) for 3 months. Parameters including pH, COD, BOD5, TSS, total nitrogen (TN), total phosphorus (TP), total coliforms were analyzed. The levels of pollutants in domestic wastewater after treatment were significantly reduced. The values of percentage removal (%) were as follows: COD 81.58%, BOD5 93.3%, TSS 67.2%, TN 58.6%, TP 85.5%, and total coliforms 90.4%. Our results also indicate that the organic loading rate (OLR) ranging between 60 and 120 kg COD/ha.day is suitable to be implemented in the actual domestic wastewater treatment.