ABSTRACT
In India, approximately 536 million livestock raised in dairy farms produce large volumes of wastewater every day. The composition of dairy wastewater includes contaminants such as organic material, solids, inorganic and organic nitrogen, phosphorus compounds, and pathogenic microorganisms. Since cattle may be a reservoir of microbial pathogens, there is a consistent concern over the contamination of soil, water, and crops when untreated wastewater is used for irrigation. Furthermore, wastewater pathogens cause infections in human beings due to use of untreated water. Regulatory frameworks for the qualitative assessment of dairy wastewater for irrigation purposes vary from country to country, and agreement with these frameworks calls for the analysis of the treated wastewater proceeding to its reuse. Constructed wetland (CW) technology has been proved as a convenient and eco-friendly tool for treatment of dairy wastewater over other treatment techniques owing to its inexpensive characteristics, less maintenance, simple design, and good efficiency of pollutants and pathogen removal. This chapter summarizes the role of the vertical CW system (vertical subsurface flow CW) in removal of pollutants and microbial load from dairy farm wastewater. Further case study of microbial removal efficiency of three different vertical subsurface flow CW systems operated for one year for dairy wastewater management has been discussed.
