Water Footprints of Vegetable Crop Wastage along the Supply Chain in Gauteng, South Africa

Abstract

Food production in water-scarce countries like South Africa will become more challenging in the future because of the growing population and intensifying water shortages. Reducing food wastage is one way of addressing this challenge. The wastage of carrots, cabbage, beetroot, broccoli and lettuce, produced on the Steenkoppies Aquifer in Gauteng, South Africa, was estimated for each step along the supply chain from the farm to the consumer. Water footprints for these vegetables were used to determine the volume of water lost indirectly as a result of this wastage. Highest percentage wastage occurs at the packhouse level, which is consistent with published literature. Some crops like lettuce have higher average wastage percentages (38%) compared to other crops like broccoli (13%) and cabbage (14%), and wastage varied between seasons. Care should therefore be taken when applying general wastage values reported for vegetables. The classification of "waste" presented a challenge, because "wasted" vegetables are often used for other beneficial purposes, including livestock feed and composting. It was estimated that blue water lost on the Steenkoppies Aquifer due to vegetable crop wastage (4 Mm 3 year −1) represented 25% of the estimated blue water volume that exceeded sustainable limits (17 Mm 3 year −1).

Progress in Water Footprint Assessment: Towards Collective Action in Water Governance

“…Three papers in this volume approach the water footprint from a supply-chain rather than from a geographic perspective. One paper considers water consumption along the supply chain of wheat bread [21], while another paper considers the water footprint of food waste along the chain [22]. A third paper studies the relation between the demand for biofuels and green water resources use and scarcity [23].…”

“…Roux et al [22] assess the blue water footprint of vegetable crop wastage along the supply chain in a case for South Africa. They focus on food waste in the value chain rather than the food finally consumed at the end of the value chain.…”

Food Waste Within South Africa and Saudi Arabia

“…The results found that 70% of the food wastage occurred on-farm at the packhouse. The results was obtained "from a large commercial farm that uses advanced technologies" (Le Roux et al, 2017). The average calculated wastage of the mentioned five vegetables along the supply chain is lower than previous estimates by Oelofse and Nahman (2013).…”

“…Lettuce has higher average wastage percentages (38%) as compared to cabbage (14%) and broccoli (13%). The wastage varies depending on the season and it is noted that some of the waste is used for beneficial purposes including animal feed and composting (Le Roux et al, 2017). A summary of their findings by commodity group along the supply chain by is provided in Table 1.…”

“…The reasons for the high wastage at the pack house include damage as a result of pests and disease and unmarketable properties. The amount of wastage is highly variable between different vegetables types, with the highest wastage occurring in perishable crops (lettuce) and lower wastage in less perishable crops (cabbage) (Le Roux et al, 2017).…”