A Domestic Sewage Treatment system (sewage treatment plant) is a facility which treats municipal wastewater, also known as sewage, before it is discharged into the surrounding environment or reused as wastewater. By treating wastewater in a sewage treatment plant and discharging the resulting effluent to the receiving water body, human influence on the receiving environment is kept to a minimum. As well, any groundwater or drinking water aquifers in the vicinity of the discharge point are protected from contamination.