Virtual water refers to the amount of water ‘embedded’ in the production of food, goods and services that we use or consume. Often invisible to the consumer, virtual water represents the hidden water footprint “behind” everyday products. Understanding this concept is essential for promoting sustainable water use, particularly in water-scarce regions.

Virtual Water in Agriculture and Food Production

The agricultural sector accounts for the majority of global water consumption, and food production is a major contributor to virtual water use. Here are some examples of the quantities of ‘virtual’ fresh water used to produce certain foodstuffs:

1 hamburger:                                      2,500 litres of water

1 litre of milk:                                     1,000 litres

1 slice of bread:                                  40 litres

1 packet of crisps:                              185 litres

1 litre of apple juice:                           950 litres

1 glass of orange juice (200ml):         190 litres

1 glass of wine (125ml):                     120 litres

1 glass of beer (125ml):                      75 litres

1 cup of tea (250ml):                         30 litres (to produce a tea-bag)

1 cup of coffee (125ml, 7gm coffee): 150 litres

1kg of roasted coffee:                        21,000 litres

1 apple:                                               70 litres

How much water do you need for 1kg of…

1kg pulses:                                         3,000 litres

1kg rice:                                              2,500 litres

1 kg citrus:                                          2,000 litres

1kg maize:                                          1,700 litres

1kg barley:                                          1,200 litres

1kg wheat:                                          800 litres

1kg potatoes:                                     500 litres

And here are some more…

1kg bread:                                           1,500 litres

1kg pork:                                             4,800 litres (estimate for a pig of 10 months)

1kg chicken:                                        3,700 litres (estimate for a chicken of 10 weeks)

1kg beef:                                             15,000 litres (3-year-old animal/200kg of meat)

Understanding the concept of virtual water is essential for addressing global water challenges. It provides a framework for understanding the hidden water costs of our consumption, the impact on water resources, and the environmental consequences of our choices.

By embracing virtual water as a tool for informed decision-making, we can work towards a more sustainable and equitable future for water resources.