Environmental Issues – Solutions

1. What are the various constituents of domestic sewage? Discuss the effects of sewage discharge on a river?

Solution:

The wastes resulting from our household activities are called domestic sewage. It includes food wastes (organic), paper, plastics, cloth etc.

There are three constituents of domestic sewage.

1. Suspended solids like slit, clay and sand.
2. Colloidal materials like fecal matter, paper and cloth fibers, microbes.
3. Dissolved materials eg. Phosphates, nitrates, sodium, calcium, ammonia etc.

The organic content of the sewage, when discharged into a river, is responsible for the microbial growth that utilizes the dissolved oxygen resulting into higher BOD (Biological Oxygen Demand).