Waste Water Story Class 7 Notes

Wastewater Story Class 7 Science Notes – Chapter 18

Wastewater is defined as used water. Used water is either rich in lather, mixed with oil, black– brown water that passes through the drains from sinks, toilets, laundries, showers, is dirty. We can reuse the wastewater by removing the pollutants.

• Sewage – The used water or the water that is generated in industries, homes, agricultural fields, etc. is called sewage. It is a waste in the form of liquid. It causes soil and water pollution. The wastewater can be treated in a sewage treatment plant which reduces the pollutants present in used water.
• Sludge – In the Wastewater treatment plant, during the process of settling of water in a large tank for solids to settle at the bottom. The solids settle at the bottom such as feaces are removed with a scraper. Please refer Waste Water Story Class 7 Notes for more revision notes.