Summary of Study Session 19

In Study Session 19, you have learned that:

1. Sanitation can be defined as the means by which human excreta, as well as community wastewaters, are collected and disposed of so that they do not cause any harm to the community. It involves protection both of human health and the environment.
2. Liquid waste can be classified as human waste, sullage, industrial waste or runoff. Different methods of waste management apply to these different categories.
3. Human waste can be contained using wet or dry sanitation systems. Wet or water-carriage methods require easy access to a water supply and are not usually appropriate in rural areas. Sanitation systems can also be classified as improved or unimproved.
4. Septic tanks offer partial, anaerobic treatment of liquid waste. The sludge has to be removed periodically and the effluent has to be disposed of via a soak pit.
5. Anaerobic biogas reactors convert liquid wastes into a sludge and biogas through anaerobic processes. The sludge can be used as a fertiliser and the biogas as a source of energy.
6. In urban areas, wastewater may be conveyed via sewers to centralised wastewater treatment plants.
7. Choosing appropriate sanitation technologies requires consideration of many factors including the needs and wishes of the local community, local environmental conditions, costs and the availability of resources.