Class 7 Science Notes for Wastewater Story (PDF) – Study Material

Class 7 Science Wastewater Story – Get here the Notes, Question & Practice Paper of Class 7 Science for topic Wastewater Story Notes. Wastewater Story Notes for Class 7 Science are here. You can download the Wastewater Story Notes PDF to study all the topics in this chapter. Moreover the Class 7 Science notes include chapter summary, definitions, examples, and key pointers for Wastewater Story. Thus if you are studying class Science (विज्ञान), then the Wastewater Story notes will help you easily understand the topic and ace it.

Class 7 Science Notes for Wastewater Story

Wastewater Story is a critical part in the study of Science. In India, it is taught in class. Therefore the Class 7 Notes for Science topic Wastewater Story have been compiled by teachers and field experts. They explain the complete chapter of Wastewater Story in one-shot.

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Wastewater Story Notes Download Link – Click Here to Download PDF

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Wastewater Story Notes for Class 7 Science

Wastewater Story Class 7 notes is as follows. You can view the document here and also download it use it anytime for future reference whenever you want to brush up your concepts of Science.

Chapter 13 – Wasterwater Story

1. Waste Water

• Water that has been drained out from the sink, showers, toilet, laundries etc. is called wastewater
• It is of black brownish colour which is rich in a lather, oil, suspended impurities etc.

2. Water Our Lifeline:

• Clean water is a basic need of a person for survival.
• Earth has 71%71% water still there is water scarcity and clean water is not available to everyone.
• Inability to access clean water leads to many water-related diseases.
• Cleaning of water is a process of removing pollutants before it enters a water body or is reused, pollutants are substances that cause contamination.
• This process of treating wastewater to remove pollutants is usually referred to as sewage treatment.

3. What is Sewage?

• Sewage is a liquid waste produced by the community of people.
• Sewage is essentially the wastewater that is released by houses, industries, hospitals, offices and rainwater that has run down the street during a storm or heavy rainfall.
• Sewage contains disease-causing bacteria and other microbes which can spread a lot of diseases.
• Discharging of sewage into the river body contaminates our source of freshwater and leads to water scarcity and other problems.
• It is also threatening the life of aquatic animals and plants.
• Therefore, sewage should be treated before discharging into water bodies.

4. Water Freshens Up-An Eventful Journey:

• The liquid waste i.e., sewage goes to the point of disposal from the point of being produced through the network of big and small pipes called sewers.
• These sewers form sewerage.
• Manholes are a small covered opening in a paved area allowing access beneath, especially one leading to a sewer and are located at every 50 m to 60 m within the sewerage.
• Manholes are found at the junction of two or more sewers and at points where there is a change in direction.
• Wastewater through the sewerage reaches the wastewater treatment plant where it has to go through a different method of treatment.
• After treatment and purification, it is discharged into water bodies and available for use.

5. Wastewater Treatment Plant:

• It is a facility where physical, chemical and biological processes are used to treat the wastewater.
• In the wastewater treatment plant, firstly wastewater is passed through bar screens which removes large objects like rags, sticks, cans, plastics etc.
• Water then goes to a grit and sand removal tank. The process of removing grit and sand is known as screening.
• The water is then allowed to settle in the large tank which is sloped towards the centre to separate sludge.
• After this, the sludge is transferred to an aeration tank where it is decomposed by the anaerobic bacteria and air is pumped to assist aerobic bacteria to grow.
• Bacteria consume unwanted matter still remaining in the water.
• The activated sludge contains 97% water this water is removed by sand drying beds or machines.
• It is necessary to disinfect water chemically with chlorine and ozone to kill unwanted bacteria and microbes.

6. Better Housekeeping Practices:

• Sewage formation should be decreased as it leads to the pollution of water.
• We must adopt some measures such as:
• Not throwing vegetable oil and fats down the drain
• Chemicals should not be discharged into the drain as they may kill the microbes that help purify water.
• Throwing used tea leaves, kitchen wastes, soft toys, sanitary towels, etc. in the dustbin.

7. Sanitation and disease:

• Poor sanitation and contaminated drinking water are the major cause of the spreading of various diseases like cholera, typhoid, polio, meningitis, hepatitis and dysentery.
• Excreting in open areas leads to water and soil pollution and these untreated human excreta are harmful to our health which indirectly goes into our body.

8. Alternative Arrangement for Sewage Disposal:

a. On-site sewage disposal system

• These toilets do not require scavenging
• Excreta from these toilets are directed into a biogas plant.
• The biogas produced is employed as a source of energy.

b. Sanitation at Public Places:

• The government has laid down certain standards of sanitation in public places.
• We all should contribute to maintaining sanitation in public places.
• We should not scatter litter anywhere as it will lead to pollution

Candidates who are ambitious to qualify the Class 7 with good score can check this article for Notes, Study Material, Practice Paper. Above we provided the link to access the Notes, Important Question and Practice Paper of Class 7 Science for Wastewater Story.

All Topics Class 7 Science Notes

Chapter wise notes for Science (विज्ञान) are given below.

• Nutrition in Plants
• Nutrition in Animals
• Heat
• Acids, Bases and Salt
• Physical and Chemical Changes
• Respiration in Organism
• Transportation in Animals and Plants
• Reproduction in Plants
• Motion and Time
• Electric Current and Its Effects
• Light
• Forest our Life Line
• Wastewater Story

Class 7 Notes for All Subjects

• Class 7 Maths Notes
• Class 7 Science Notes

NCERT Solutions for Class 7 Science Wastewater Story

The Wastewater Story notes here help you solve the questions and answers. Also, you can complete the Class 7 Wastewater Story worksheet using the same. In addition you will also tackle CBSE Class 7 Science Important Questions with these Class 7 notes.

However if you still need help, then you can use the NCERT Solutions for Class 7 Science Wastewater Story to get all the answers. Wastewater Story solutions contain questions, answers, and steps to solve all questions.

Notes for All Classes

• Class 6 Notes
• Class 7 Notes
• Class 8 Notes
• Class 9 Notes
• Class 10 Notes
• Class 11 Notes
• Class 12 Notes

Wastewater Story Notes for Class 7 Science – An Overview

Name of Topic	Wastewater Story
Class	6
Subject	Science
All Class 7 Science Notes	Class 7 Science Notes
All Class 7 Notes	Class 7 Notes

Class 7 Wastewater Story Notes for All Boards

You can use the Class 7 Science notes of Wastewater Story for all boards.

The education boards in India for which Wastewater Story notes are relevant are – CBSE, CISCE, AHSEC, CHSE Odisha, CGBSE, HBSE, HPBOSE, PUE Karnataka, MSBSHSE, PSEB, RBSE, TBSE, UPMSP, UBSE, BIEAP, BSEB, GBSHSE, GSEB, JAC, JKBOSE, KBPE, MBOSE, MBSE, MPBSE, NBSE, DGE TN, TSBIE, COHSEM, WBCHSE.

Therefore you can refer to these notes as CBSE, CISCE, AHSEC, CHSE Odisha, CGBSE, HBSE, HPBOSE, PUE Karnataka, MSBSHSE, PSEB, RBSE, TBSE, UPMSP, UBSE, BIEAP, BSEB, GBSHSE, GSEB, JAC, JKBOSE, KBPE, MBOSE, MBSE, MPBSE, NBSE, DGE TN, TSBIE, COHSEM, WBCHSE notes for class Class 7 / Class / Science for the topic Wastewater Story.