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Class 7
Science
Wastewater Story
what is sewage explain why it is harmful to disch...

Question:
What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas.

Answer:

Sewage: The waste water and faeces (human excretion) from homes and other buildings which is carried into the sewers is called sewage. Sewage includes household wastewater from kitchen sink, washing machine, washbasin, bathroom shower, bath tub and faeces from the toilet. Sewage is also produced and released by shops, offices, schools, hospitals, factories, industries and all other places where humans work or live. Sewage also includes rainwater that has run down the streets and roads during rains carrying harmful substances with it which also spreads various diseases along it, and flows into sewer pipes. Sometimes, sewage contains harmful and poisonous chemicals that are being discharged by factories and industries. Most of the dirty water contains dissolved and suspended impurities in it which are known as contaminants or pollutants.

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Question:
What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas.

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Question: What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas.

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Question:
What is sewage? Explain why it is harmful to discharge untreated sewage into rivers or seas.