What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas
Sewage is the wastewater containing both liquid and solid wastes produced by human activities from homes, industries, hospitals, offices, etc.
Sewage contains various contaminants including disease-causing bacteria and other microbes. If untreated sewage is discharged into rivers or seas, then the water in the rivers or seas would also get contaminated. If this contaminated water is used for drinking, then it can cause diseases such as cholera, typhoid, dysentery, etc. which may lead to death. That is why it is harmful to discharge untreated sewage into rivers or seas.
Sewage is a liquid containing wastes which is disposed by households, industrial and agricultural activities in water. It is harmful to discharge untreated sewage into rivers or seas because it can pollute the whole sources of water. Sewage contains harmful substances and disease causing organisms. It is therefore dangerous to release untreated sewage in water.