Abstract:The current water scarcity situation in South Africa is a threat to sustainable development. The present paper has assessed the water footprint of milk produced and processed in South Africa using the procedures outlined in the water footprint assessment manual. The results show that 1352 m 3 of water is required to produce one tonne of milk with 4% fat and 3.3% protein in South Africa. The water used in producing feed for lactating cows alone accounts for 86.35% of the total water footprint of milk. The water footprint of feed ration for lactating cows is about 85% higher than that of non-lactating cows. Green water footprint accounts for more than 86% of the total water footprint of feed ration for lactating cows. Green and blue water footprints are the highest contributors to the total water footprint milk production in South Africa. Water used for feed production for both lactating and non-lactating cows accounts for about 99% of the total water footprint of milk production in South Africa. Particular attention should be given to feed crops with low water footprints and high contribution to dry matter to provide balanced ration with low water footprint. Water users, managers and livestock producers should pay attention to green and blue water consumption activities along the milk value chain and design strategies to minimize them. Corn, sorghum and lucerne production under irrigation in the greater Orange River basin is sustainable, whereas oats production for silage in the same catchment area is not sustainable. Our findings provide the rationale for dairy producers and water users in the dairy industry to get an understanding of the degree of sustainability of their input and output combinations, production choices, and policy interventions, in terms of water use.

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The Global Water Footprint Standard approach was used to calculate the volumetric blue and green water footprint indicator for lucerne production as important feed for dairy cows in a major lucerne production region in South Africa. The degree of sustainability of water use then was assessed by comparing water use to water availability for the region. The results show a volumetric water footprint indicator of 378 m 3 /tonne of lucerne. Of the total blue and green water footprint, 55% is green water footprint and 45% is blue water footprint. Thus, albeit in a major irrigation area of South Africa, the largest component of the total water requirement is met by effective rainfall. The assessment of sustainability of water use showed that the period when lucerne requires irrigation water furthermore corresponds to the period where the water scarcity index is smaller than 100%. The water footprint thus is considered sustainable from an environmental perspective. This research proves the benefit of using context specific data to assess the water footprint of a crop, and the importance of a sustainability assessment in a water footprint assessment to generate information useful for informing water users and managers towards sustainable freshwater use.