1. All the waste water released by homes, industries, hospitals, offices and other users are collectively called Sewage.
2. Sewage is a liquid waste.
3. Most of it is water, which has dissolved and suspended impurities, disease-causing bacteria and other microbes. These impurities are called contaminants.
4. If this is discharged into canals, it causes a lot of harm to animals, human beings, aquatic animals and plants if this water used.
