Informed consumers can make better purchasing decisions, informed producers can manage water use better. Virtual water is a representation of the ‘water footprint’ embedded into the production process. Simply put it is the litre value of a consumable item and can aid in both producer and consumer decision making.

In South Africa agriculture accounts for 60% of total water usage.

With such high volumes of water being used, farmers and consumers who wish to be ‘water-wise’ can make use of virtual water to keep track of their usage and see how much water they are ‘using’ per purchase.

Rainbow Reservoirs, a manufacturer of sectional steel, bolted-panel tanks used throughout Africa, put together a virtual water list that may surprise you.

Freshwater in litres per item

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

Freshwater per KG

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

Common goods

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)

Keeping score

While such lists may inspire behaviour changes in the consumer, these values can aid the agricultural sector which can use them to benchmark their water usage.

This can track high water use and can be used to plan ahead. Rainbow Reservoirs manufacture tanks for water storage that are used in the agricultural space, and when farmers use virtual water to plan they have to rely on properly manufactured tanks that can store and manage the water they need for production.

One piece of equipment that aids the agriculture sector is the Levitell Water Level from Rainbow Reservoirs,  which aims to take the guesswork out of tracking a tank’s water reserve. By actively tracking and ensuring correct water use farmers can ensure the water they use is going to where they need it to go.

Another measure of sustainable water usage is rainwater harvesting, and storage which can used to augment water supply for stressed periods. Part of Rainbow Reservoir’s offering is the installation of these rainwater harvesting reservoirs which are used throughout South Africa in the commercial, industrial, and agricultural sectors.

Using virtual water to benchmark practices while relying on purposeful technology can ensure sustainable farming practices using the planet’s most valuable resource.