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Flushing the biggest water hog in the building

Non-sewered sanitation (NSS) technologies are not only a feasible solution for poor areas of the country that lack basic services. It is illogical that South African homes in the urban areas use up to 12l of potable water just to flush their toilets. This is considering South Africa’s severe water crisis, with many areas of the country already experiencing shortages due to severe droughts. The challenge is being compounded by dilapidated infrastructure, mismanagement and load-shedding.

Conventional toilets are extremely water intensive contributing to about 30% of a household’s total water consumption. Certainly, water-saving toilets play an important role in reducing the water footprint of homes and buildings. Some of these technologies consume up to 20% less water than traditional flush toilets. However, with about 63% of the population using flushing toilets, Sello Mokawane, President of the Institute of Plumbing South Africa (IOPSA), says that these technologies are insufficient intervention.

“More will need to be done considering the sheer extent of the water and sanitation challenges with which we grapple. While water shortages are becoming a common occurrence in the urban nodes, many South African citizens who live in the rural areas and informal settlements have had to do without this basic human right for many years. It has long been their norm, while quality drinking water is being flushed down the toilet in the middle- and high-income areas. At the same time, our existing sanitation infrastructure is buckling under the strain of rapid urbanisation and development, compounded by mismanagement of this infrastructure. It is a concern that more than 330 of our 852 wastewater-treatment works (WWTWs) are in a critical state. This is happening while many of the rural areas and informal settlements have never had access to sanitation infrastructure that distances people from harmful pathogens and bacteria. Both situations also compromise the quality of our clean water resources. Only 54% of the population can access clean drinking water and about 33% of South Africans do not have sanitation services for the safe handling and management of waste. Considering this growing backlog, it is questionable whether we will meet Sustainable Development Goal 6, which aims to provide access to quality water and sanitation to all South Africans by 2030. SDG 6 is also in line with

Vision 2030 of the National Development Plan and Medium-Term Strategic Framework Outcome Targets, as well as a driver of the National Water & Sanitation Master Plan. NSS technologies can be implemented quicker and more cost-effectively than large, centralised systems and are, therefore, a way of achieving our water and sanitation goals,” Mokawane says.

IOPSA members are increasingly expanding their skills to service the growing “green” plumbing market. A case in point is the role that they are playing in helping property owners to safely use greywater for applications such as flushing toilets. They are also equipped with the skills that are needed to install, maintain and repair rainwater harvesting systems. These significantly reduce water footprints of houses and buildings, especially when rainwater is used for water-intensive toilet flushing purposes.

Certainly, IOPSA members are also knowledgeable in the installation, repair and maintenance of non-waterborne sanitation systems. Their skills and experience encompass all the technologies that are currently being used in the country, such as pit latrines, as well as Ventilated Improved Pit and Ventilated Improved Double Pit Toilets. This is in addition to short-cycle alternating double-pit toilets; pour flush latrines; and urine diverting dry toilets. If properly installed, these technologies provide an affordable and practical solution for rural and peri-rural areas where conventional water-borne sanitation systems are not feasible. Certainly, there has also been a growing interest in the technology in urban areas where municipal services are deteriorating at an alarming rate. Property owners are, thus, increasingly exploring ways of reducing their reliance on municipal supplies.

IOPSA members are trained to install, maintain and repair these technologies according to SANS 10400-Part Q. This national standard ensures the healthy handling and treatment of effluent for non-waterborne sewage systems.

However, new and more efficient NSS systems are being introduced to the country that bridge the huge divide that currently exists between conventional pit latrines and waterborne sewage solutions. They are also more socially acceptable alternatives to existing non-waterborne sewage systems. This should help to drive their uptake in the urban areas.

Enterprising plumbers have, therefore, already familiarised themselves with the new SANS 30500 standard which enables the testing and validation of these next-generation NSS technologies.

Notably, IOPSA recently participated in two field studies involving NSS systems. Plumbing students were also invited to participate to expose them to these exciting new “green” plumbing technologies.

The stellar work in mainstreaming these technologies is being driven by the Water Research Commission’s Sanitation Transformational Initiative.

It is being supported by government through impressive legal and policy frameworks. A case in point is the national sanitation policy which focuses on the entire sanitation value chain. In doing so, it recognises the economic value of sanitation and emphasis is given to both urban and rural sanitation, as well as on- and off-site systems.

The previous Minister of Water and Sanitation, Nomvula Mokonyane, was very outspoken about the applicability of this technology in the urban areas. She said that government needed to “begin challenging the property development sector through regulation and licensing to invest in developing properties less reliant on water for sanitation”. This would “ensure that we introduce alternative solutions to low-, middle- and high-income areas”.

These NSS systems are prefabricated integrated treatment units. They comprise a toilet at the front end and a treatment facility at the backend. They collect, convey and fully treat the waste that is introduced to the system. Therefore, they are not connected to any sewer or drainage network that sends sewerage to a wastewater-treatment works.

An example of such technology is a toilet that uses a full water cycling process to treat sewage. A rainwater collecting system can also replenish the water to the processor for treatment before it is recycled to the storage tank for flushing. Blackwater from the toilet is pumped up to the sewage processor for treatment and then recycled to the storage tank for flushing. The core of the technology is a sophisticated biofilm membrane reactor treatment process. It produces a stable and clean effluent that is further disinfected to ensure that it is safe for reuse.

“I do believe that these systems will gradually become the norm as opposed to the alternative. This is considering the ease at which they can be implemented and their cost-efficiency versus large, centralised sanitation infrastructure. Between 2015 and 2030, it is estimated that 18,3-million South Africans will require basic sanitation services to end open defecation. This calls for a US$370-million annual investment into sanitation infrastructure. Add to this the need to safely manage faecal sludge from all sources, including WWTWs, which requires a further annual US$970-million investment. In 2019/2020, South Africa only invested R17,5-billion into sanitation, which was nowhere near enough to address existing backlogs and new services. It is a significant challenge that requires ‘out of box’ thinking with the diverse skills and experience of the plumbing fraternity harnessed as part of the solution,” Mokawane concludes.