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How to calculate leach pit and soak pit size of twin pit toilet for school ?


I am designing a twin pit latrine for a school of strength 200. how much leach pit and soak pit size is required for a 8 hr school? I need to know the standard calculation for the same. The school is located in plane (agricultural land) , ground water level is also around 10 m below ground.Kindly suggest: 1.leach pit size 2. Soak pit size 3. water requirement for handwash,flushing toilet, cleaning toilet. anal cleansing.

1 Answer


I think the best discussion of the design of leach pits is to be found in The design of pour flush latrines published by the World Bank. It is a bit dated but still sound in my opinion.