7. What is sewage? In which way can sewage be harmful to us?
The municipal wastewater that is drained into sewers and drains is known as sewage. It contains a large amount of organic matter, microbes, human excreta etc. When sewage is not treated properly, it degrades the quality of water and acts as a breeding site for the mosquitoes. This may lead to diseases like dengue, malaria etc in nearby communities. Thus sewage can be harmful to us.