Let's see what you have understood

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Across
  1. 4. A pipe carrying sewage
  2. 6. Waste matter discharged from human body
  3. 7. Used water
Down
  1. 1. liquid waste products
  2. 2. Micro-organisms which causes cholera
  3. 3. A chemical to disinfect water
  4. 4. A word related to hygiene
  5. 5. Solid waste extracted in sewage treatment