South Africans flush toilets with drinkable water: study in Cape Town looked at using seawater instead

By Teboho Mofokeng

As the planet gets hotter and freshwater sources dry up, cities and towns will not be able to continue the global norm of using millions of litres of clean, drinkable water to flush toilets. South Africa’s Water Research Commission recently commissioned a study into using seawater to flush toilets in Cape Town. Water engineering lecturer Teboho Mofokeng researches water management and reuse in South Africa and she co-authored the study. She spoke to The Conversation Africa about Capetonians’ willingness to pay up to 10% more on their water bills to use seawater to flush their toilets, as long as it doesn’t smell or stain their toilets.

What are the problems with how toilets are flushed in Cape Town?

The first problem is that the city uses clean, treated drinking water for toilet flushing. Generally, 20%-30% of the city’s drinkable water supply to households is used to flush toilets.

The