2. Water usage and management
2.1. Water in agriculture and food
It is predicted that population growth will necessitate 60%
more food by 2050 and thus a 19% increase in agricultural
water use (UNFAO, 2012). Allied to this, the foods eaten by the
people have a significant impact on water consumption. The
increasing population in the middle class worldwide leads to
more people choosing western-style diets, which are high in
protein, sugar and fat, all of which are expensive in terms of
water for food production.
The water consumed in the production of an agricultural
or industrial product is termed ‘virtual water’ (Renault, 2002).
Every day a person drinks 2–4 litres of water, but they will also
consume 2000–5000 litres of virtual water embedded in their
daily food. There is a hidden cost of water in the food we eat.
Beyond agriculture, the biggest water use in the food
industry is the cleaning of processing equipment/plants and food products. This can account for up to 70% of a factory’s
water usage (WRAP UK, 2013). A study examining the use
of recycled water in Australia (Martin-Nagel et al., 2011)
indicates that recycling water during food production is
acceptable to the public if the water has been collected,
treated and processed to drinking water quality.