DOMESTIC WASTE-WATER TREATMENT THROUGH CONSTRUCTED WETLAND IN INDIA

The paper highlights the use of constructed wetlands for the removal o f BOD, nitrogen, phosphorus and pathogens from primary treated wastewa ter. The constructed wetland consists of emergent macrophytes Typha la tifolia and Phragmites carca grown in cement pipes having 0.1256 m(2) area and 0.8 meter deep filled with 30% soil and 70% sand. The hydraul ic loadings were maintained at the rate of 5 cm per day. The BOD remov al in wetlands was observed to be 78-91%. The nitrogen content reduced from 30.8 mgl(-1) to 9.5 mgl(-1) whereas phosphate in treated wetland effluent was 9.6 mgl(-1) as against the mean inflow total phosphate c ontent of 14.9 mgl(-1). The Country's first constructed wetland, of 90 m x 30m size, was installed at Sainik School, Bhubaneshwar in the Stat e of Orissa. Two types of macrophytes, viz. Typha latifolia and Phragm ites carca, were planted. At present 180-200 m(3) wastewater is being treated through wetland. BOD and nitrogen removal were 67-90% and 58-6 3% respectively. The constructed wetland treatment was found to be eff icient in removal of BOD and N, and economically viable, The system, b eing easy to operate and low cost can provide an economical viable sol ution for wastewater management.