The terms sewage, sewers and sewerage are interlinked with each other. Can you explain, how?

Sewage is wastewater that flows down the drains of houses, industries, hospitals, offices, fields, etc. Rainwater that runs down the streets during storm or heavy rain also adds to the sewage. This is because rainwater falls on rooftops and roads and carries harmful substances with it. The dissolved and suspended solid impurities present in sewage are called contaminants. They include organic and inorganic impurities, nutrients and disease-causing bacteria and other microbes. Sewage goes through a system of pipes, called sewers.

Sewer is an underground pipe for carrying off drainage water and waste matter. Sewers are linked to each other to form a network called a sewerage system.