However, with Johannesburg, Tshwane, and Cape Town all having less than ten years of useful landfill life left, the pressure is on to find alternative waste-treatment technologies (AWTT), argues Nicola Liversage, AECOM's Business Unit Director - Environment, Africa.

South Africa's eight Category 'A' metropolitan municipalities have the highest population numbers, and therefore generate the largest waste volumes, at about 20 million and 10 million tons of waste a year respectively, of which the bulk is landfilled.

Landfilling at an average density of 1 t/m3 means that municipalities need an annual landfill space of about 10 million m3. While some municipalities like eThekwini boast a useful landfill life of 120 years, others such as Johannesburg, Cape Town and Tshwane have a limited useful landfill life of less than ten years.
"Therefore the need to investigate AWTT is crucial for diverting waste from landfill," highlights Liversage. Johannesburg, the eThekwini Metropolitan Municipality, Cape Town, and the Sedibeng District Municipality have all completed AWTT feasibility studies, while the Drakenstein Local Municipality in the Western Cape has finalised a waste-to-energy feasibility study. AWTT feasibility studies are also under way in Tshwane and Ekurhuleni.

Material recovery facilities (MRFs) have been established in some municipalities in order to recover recyclables. However, these are hampered by the low rate of recovery of recyclables. The absence of separating waste at source means facilities are operated as 'dirty' MRFs with high contamination rates and lower recovery rates, compared to 'clean' facilities with low contamination rates.

In addition, some South African municipalities are piloting separation at source, but with a minimal response. In the European Union (EU), on the other hand, separation at source has been key in enabling the diversion of waste from landfill by means of recycling, composting, and incineration. In South Africa, waste incineration is still small-scale, used mainly for the thermal treatment of healthcare and some hazardous waste.

With regard to the challenges facing waste management in South Africa, Liversage points to environmental authorisations, permitting, licencing and social issues as the main stumbling blocks. "In fact, it can take up to ten years between identifying a suitable site and actually commissioning a landfill," she adds.

Although the capex and maintenance costs of technologies for treating waste are substantial, landfilling remains less expensive than AWTT. However, the cost of landfilling may be even higher at the end of the day, given the cost of managing a landfill upon its closure. The life of a landfill may stretch to about 50 years after it closes. In addition, the absence of carbon taxes means that landfilling continues to dominate waste management in South Africa compared to AWTT, which is increasingly the norm in the EU.