Solution:
Sewage is a water-carried waste matter that is discarded away in sewers and drains.
It is also known as domestic or municipal wastewater.
Sewage can be harmful due to several reasons are:
- It includes wastes containing organic matter and microbes which are pathogenic and can cause several water- borne diseases.
- Sewage provides a breeding place for disease causing harmful insects and microbes.
- Sewage is a major cause of polluting drinking water.
- When sewage enters a lake or stream, it destroys or pollutes the water body affecting the organisms present in the water bodies