20.5.2  Pour-flush toilets

A pour-flush toilet is like a cistern flush toilet except that instead of the water coming from the cistern above, it is poured in by the user. When the water supply is not continuous, any cistern flush toilet can become a pour-flush toilet. Water is simply poured into the bowl manually from a bucket or a jug to flush the excreta; approximately 2–3 litres of water is usually sufficient. Pour-flush toilets share all the advantages of cistern flush toilets but use a lot less water. The wastewater should be disposed of to a septic tank or seepage pit, also known as a leach pit (Figure 20.8).

The pit will contain excreta, cleansing water and flush water. As this leaches from the pit and migrates through the soil, faecal organisms are removed. In some geological conditions, there is a risk of groundwater pollution; therefore, this method is not always recommended.

Pour-flush latrine design
Figure 20.8  Pour-flush latrine design. (Source: as Figure 20.1)

20.5  Water carriage systems of human waste disposal

20.5.3  Aqua privy