Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions.

Match the following words to their correct definitions.

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Ato Aschalew, a resident in the outskirts of your town, consults you about building a latrine in the compound of his house. He is an open-minded man who is keen to improve life for his family. He has a wife and three young children, and his elderly mother also lives with them. He doesn’t have a tap in his house and gets water from a nearby well. The area has heavy soil and the rock below is impermeable.

  1. Which types of latrine are possible choices for him?
  2. Which types of latrine would you recommend, and why?
  3. What other advice would you give him about the location, design and construction of the latrine?

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Galawdeyos and his family comprise a total of seven people. They plan to build a new VIP latrine with a pit with a diameter of 1 m in their back yard. Calculate the depth of pit required if they intend that it should last them three years. Take the sludge accumulation rate to be 40 litres per person per year.

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Depth of pit \=\frac{P \times S \times N}{A}\+0.5 m

P = 7

S = 40 litres per person per year = 0.04 m3 per person per year

N = 3 years

A is \frac{\pi \times d^2}{4} or \frac{3.142 \times 1^2}{4}\ = 0.79 m^2

depth = \frac{7 \times 0.04 \times 3}{0.79} + 0.5 = 1.6 m

Which of the following statements are false? In each case explain why it is incorrect.

  1. For sustainability, it is best to use locally-available materials and skills when constructing latrines.
  2. The aim should always be to have water-borne toilets such as the WC.
  3. Constructing a pit latrine with a mound ensures that any water drains away.
  4. The raised footrests in a latrine help in the proper use of the facility in darkness.
  5. The cost of the latrine to the user is immaterial, since good health from proper sanitation is priceless.

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B is false. Water-flushed toilet systems should only be considered if a continuous supply of water is available.

E is false. Latrines need to be affordable for people to adopt them.