Abstract: In the present study, earthworm species Eisenia fatida has been used for treating and reclaiming the domestic wastewater (sewage). For this purpose, a field scale vermifilter was designed and constructed, from which the domestic wastewater was allowed to pass through. The performance of the vermifilter was assessed by evaluating the physico-chemical and microbiological characteristics of the effluent. The study revealed that presence of earthworms in the vermifilter bed can efficiently remove pollutional parameters like biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total dissolved solids (TDS) from the wastewater and at the same time, concentration of dissolved oxygen is increased / improved. More significantly, the pathogenicity is reduced in terms of total coliforms and faecal coliforms. The combination of earthworms with microorganisms proves to be very supportive in fighting against the organic matter and pathogens present in wastewater, as the earthworms are best known for their waste management capacity. They assist in maintaining the aerobic conditions in wastewater with their famous burrowing action.
Keywords: Domestic wastewater, vermifilter, BOD, COD, total coliforms, faecal coliforms.