Flooding due to climate change is expected to affect sanitation because it damages drainage infrastructure and wastewater treatment facilities. During flooding, the flood water can burst sewer lines, where they exist, and overwhelm waste treatment plants. In other areas, pit latrines and septic tanks are liable to overflow. Sanitation facilities in urban and slum areas are highly vulnerable to flooding because they are often poorly designed and constructed.
In rural areas where the latrine coverage is low and open defecation is still a widespread practice, the impact of flooding on sanitation is huge. Even where latrines exist, they often have slabs made of wood and mud, which are much more vulnerable than concrete slabs if there is a flood. Most latrines do not have a proper roof, substantial walls or a diversion ditch to divert flood water and stop it entering the latrine. If the latrine overflows, this leads to contamination of water sources and outbreaks of diarrhoeal diseases, as we described in Section 11.1. The health problems caused by flooding are aggravated when people are displaced by the flood into overcrowded refugee camps with poor sanitation facilities and water supplies. When they return to their homes after the flood ends, their traditional sources of water have been contaminated by pollutants and disease-causing organisms (International Federation of Red Cross and Red Crescent Societies, 2005).
Drought and water shortages also have considerable impact on sanitation and hygiene. Nowadays, an increasing number of households in better-off urban areas use water-flush toilets, which require several litres of water to flush human excreta into a septic tank or sewer. Water shortages mean that the excreta cannot be flushed away, so bad odour builds up which attracts flies. This increases the risk of transmitting faecal organisms on the hands. Water shortages also mean that people cannot maintain their personal hygiene by washing their hands and face or bathing their body.
To conclude this study session, consider the following question before moving on to the next which describes the importance of developing resilience to climate change and coping strategies for the future.