A Sewage Treatment Plant is a type of wastewater treatment which aims to remove contaminants from sewage. Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. Physical, chemical, and biological processes are used to remove contaminants and produce treated wastewater (or treated effluent) that is safe enough for release into the environment. Essentially, a treatment plant operates by circulating air to encourage the growth of bacteria to break down sewage. The Sewage Treatment Plant is very effective and useful.