Need for Treatment of Sewage

Nearly 75% of the water supplied returns back in the form of wastewater. As there is a need for water supply system, there is an equal necessity to dispose the wastewater. The night-soil and urinary content of domestic sewage (originating from residential areas) consists of potentially most dangerous organisms. Such organisms are responsible for the occurrence and spread of water-borne diseases.

Sewage treatment is meant the various steps undertaken in the process of transferring sewage into a harmless liquid. That is to render sewage inoffensive without causing nuisance or odour and to reduce or eliminate any possible contaminations of water supplies, bathing areas, etc., by the untreated or un-disposed sewage.