The high capital, operational and maintenance costs of municipal wastewater treatment plants in Iran are a concern for the government. Wastewater treatments in natural systems have shown suitable methods for their low cost. The performance of a pilot-scale subsurface constructed wetland with Phragmites australis to treat municipal wastewater has been investigated. The purpose of this study was to determine the surface area requirement per person in an arid region to achieve an acceptable quality in terms of discharge standards.
Experiments were carried out in two cells (15 × 10 mxm) with media size ranging from 4-8 mm. One cell was used as blank (unplanted) and the other one was planted. Different hydraulic loading rates ranging from 5 to 20 L/min were used. Minimum land requirement was determined to be 1-2 m2/P.E. to reduce COD (86±4%), BOD5 (90±3%), TSS (89±4%), TN (34±6%), TP (56±5%) and fecal coliform (>99%).