About 65% of the South African population has access to water-based sanitation, such as flushing toilets connected to a sewer network, septic tank or holding tank. Another 19% have improved ventilated pit latrines, while 13% of people have ductless pit toilets.
The rest of the population have flush toilets, chemical toilets or composting toilets, or people use buckets. Unfortunately, around 1% of South Africans still practice open defecation because they don’t have access to any kind of toilet.
South Africa is a water-scarce country that has faced extreme weather events in recent years. For example, in 2018, Cape Town faced a severe drought and the possibility of running out of water. More recently, the east coast city of Durban was affected by flooding that damaged water and sanitation infrastructure. With the country’s challenges around water availability and management, it is simply not feasible or feasible to continue with water-based sanitation.
Conventional flush toilets use around nine to 12 liters of water per flush. And that is drinking water.
Furthermore, according to the latest South African Green Drop report, the performance of current conventional wastewater treatment works is alarming. Only 23 of the 995 wastewater treatment works evaluated reached the Green Drop status with a score higher than 90%.
We find it practical to transition to adopting non-sewer sanitation technologies.
What are sewerless sanitation systems?
Sewerless sanitation technologies collect, transport and fully treat the acceptable input into the site.
Instead of your waste going from your toilet through a sewer to an off-site treatment plant, this technology treats your waste on-site and allows treated products to be safely reused or disposed of.
These technologies can be installed in the home and larger systems can be implemented for schools or communities. They consist of a front part, which is the sanitary facility, and a rear part, which is the treatment facility.
The HTClean, one of the reimagined toilets funded by the Gates Foundation, developed for a single household, uses a vacuum flushing mechanism. This reduces the water needed to 0.2-0.9 liters per flush. Urine and fecal matter are mechanically separated at the rear and treated by high-temperature, high-pressure processing. The treated liquid outlet is reused for washing.
What are the benefits of this toilet technology?
Sewerless sanitation is less dependent on water and its treated production can be reused.
Sewerless sanitation fully treats feces and urine. The treated solid output can be used as a fertilizer, while the treated liquid output can be used for washing or irrigating crops. Our fecal matter and urine is a valuable resource.
How close is this to being a reality in South Africa?
I am involved in training and awareness of a global standard called ISO 30500, which has been adopted in South Africa as SANS 30500. This standard provides guidance for the design, performance and safety requirements of non-sewered sanitation systems. It also considers the sustainability of these systems over a functional lifetime.
At the University of KwaZulu-Natal, on behalf of the Water Research Commission, we are coordinating the development of a certification scheme that will allow these technologies to be certified to the standard and enter the market.
Two South African companies have licensed two technologies that were developed through the Bill & Melinda Gates Foundation-funded Reinvented Toilet Challenge for manufacture in South Africa. These technologies are being tested in the field through the South African Sanitation Technology Enterprise Program. The program provides a platform for sanitation innovators and commercial partners to take their technologies from the prototype development phase to commercialization.
The water and sanitation department has already identified the benefits of sewerless sanitation and recently launched the technical coordination committee for sanitation technology. The committee’s role is to help develop a process for evaluating and validating appropriate sanitation technologies, certifying and accrediting them, and guiding their adoption and commercialization. However, while the regulator can make recommendations, it is really the municipalities that make the decisions.
I believe that quality assurance through certification will provide users and authorities of water services and municipalities the peace of mind of knowing that these technologies are safe and reliable.
While the cost of developing, testing and certifying sewerless sanitation technologies may seem high now, it all comes down to economies of scale. Over time, increased demand will make these systems cheaper to manufacture and more affordable for homes.
Ina Skosana interviewed Dr. Preyan Arumugam-Nanoolal for this article, which was first published by The Conversation (Africa) and is republished here in edited form under the Creative Commons license. You can read the original article here.
