Sewage or effluent is waste water that is produced by humans or industry. But today, through some methods, these waters are treated and returned to the cycle of use. In general, there are two types of wastewater or effluent that can be treated. Although the collection of surface water and drainage began in ancient times, the effects of wastewater collection date back to the early nineteenth century, followed by the untreated wastewater treatment in the late century. It took place in the nineteenth and early twentieth centuries. Unlike urban water supply and wastewater collection techniques, which have a relatively long history of several thousand years, wastewater treatment and treatment today has a short history and only in historical writings full of commands and sayings about water, Especially river water is mentioned. First, about a hundred years ago, when the relationship between the effects of pathogenic bacteria and germs on the prevalence and spread of diseases became apparent, humans began to think about purifying contaminated water. Cognition (the emergence of theory and pastor in the second half of the nineteenth century in the field of public health) has emerged.