• In a bid to save water Bernelle Verster skipped the toilet when building her house. 
  • Instead she keeps her own waste for compost. 
  • Dry sanitation holds promise as Cape Town's water crisis drags on.


Self-proclaimed water maverick Bernelle Verster lived in a shack for two years while building an eco-smart house. When it was done, her house still lacked anything resembling a traditional toilet. It does have a bright red, custom-made dry dumper, however.

This 36-year-old bio-process engineer has spent a decade in water, waste and sanitation learning the ins and outs of turning human waste into a valuable resource. It led her down the path of designing dry toilets for her masters and PhD degrees.  

 “When we think about dry toilets we generally think about long drops and pit latrines. It’s not about that. Mine is literally a 25 litre plastic bucket with some sawdust,” says Verster.

35.8% of the world’s population still lacks access to any proper sanitation facilities.

Dry toilets like Verster’s separate urine and faeces. If managed properly they produce no smell, but do produce plant food.

“I have a new house with a new garden, so any nutrients will do well in the soil. I don’t have the money to and buy tons and tons of compost, so it just makes sense to use my own compost. Urine for example is the best source of nutrients that I can throw straight into the garden.

For Bernelle Verster, when it came to Cape town’s drought, the business of brown and flushing it down was a real crappy problem. In her belief, toilets wasted too much water.

Among her other architectural eco-savers like double glazed glass, locally-sourced timber walls, and corrugated ceilings, Verster has also has incorporated rain harvesting ponds. 

“Look at how cities function. Look at how much money we spend treating our waste water. Our estuary down the road suffers from sewage overflows. A dry water system doesn’t have those negative impacts,” says Verster.

Read: This entrepreneur is making 1,000 litres of water a day from Cape Town's air

With Day Zero looming, alternative dry sanitation solutions are getting more attention. Using grey water is one solution – as long as the sewage systems are functional. The question is what happens when there is none. 

Pros and cons of dry sanitation solutions

Compared to flush toilets, dry toilets lack scale, and the convenience of everyone's waste being processed at one, central location. 

“When you think about sanitation and possibly health diseases. The convenience about flush toilets is that you just flush and forget,” says Verster.

“If we hit Day Zero and everyone can only flush their toilet once a day with your leftover 25 litres, we would need 23 million litres of water to flush everyone’s toilet once."

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