Africa is developing at a fast pace in the 21st century and this is accompanied by continuing urbanization. The economic growth rate, measured in terms of growth in gross domestic product (GDP), has been of the order of 4-5% p.a. for much of the past decade, well above the global average. With these increases in economic wealth and urbanization, people are becoming more affluent and demanding more consumer goods. This implies not just growth in the volumes of materials entering and leaving cities, but also a qualitative shift in what is increasingly called ‘the metabolism’ of the cities where this consumption is taking place, a trend expressing itself by a shift in provisioning from the traditional market to the supermarket. It stands to reason that with these changes in consumption comes an increase in the quantity and variety of waste generated. Past studies already show under-capacity waste management infrastructure and insufficient investment in urban waste management in Africa. The objectives of this dissertation are to 1) Develop and present models of the food material flow profile for a traditional market and supermarket consumer from production to disposal and develop waste flow profiles for both the traditional market and supermarket consumer; 2) Analyse the effect of change in food provisioning on the waste generated ; and 3) Describe the impact of this effect given the current waste management capacity and structure in African cities. To better inform waste management planning in African cities undergoing such a metabolic transition, metabolic flow models have been developed to describe the acquisition of food from a traditional market vs. a supermarket. Consumer food flows are formulated based on cultural profiling and quantified via the daily nutritional and energy requirements of a healthy person. The associated waste profiles of these food items are then obtained by reading from packaging and processing data sets. Results from the model confirm that there is a change in the waste profile associated with a shift in consumption from the market to the supermarket. The model is first applied to three diets: student, working class and vegetarian. The model shows 1) a shift of 14 to 58% of the organic content from the post-consumer waste to the supply chain where this food is processed and 2) a 3-10 fold increase in the inorganics in the post-consumer waste associated with food packaging used in supermarkets. These results are then interpreted for three case study cities: Kisumu in Kenya, Kitwe in Zambia and Harare in Zimbabwe, showing that this shift is being seen in all these cities. The shift in the organic waste is within the same range across all three cities within each income group. The increase in the inorganics however differs, being higher in Kitwe and Harare compared to Kisumu. This shows that the magnitude of changes in food-related waste generation is affected by the type of food consumed. Results from waste management surveys for the same case study cities show that there is a lack of sufficient capacity to provide adequate service to the people in all three cities. The city councils do not have the resources to collect and dispose of all waste generated in the cities and the private sector only provides services where it makes business sense. There is some effort in all three cities devoted to recycling and to management of organic wastes, but this is also inadequate and likely to be overwhelmed by the continuing metabolic shift. The findings point to the need for waste management becoming more commercially viable, adaptive and inclusive. There is also need for a sociocultural attitude change among the residents at household level who still look down upon waste management.

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