Hong Kong's average daily domestic fresh water consumption per capita is 130 litres. Around 40% of that is used for bathing, 10% for laundry and the remaining 50% for cooking and other purposes.
130 litres is just a visible part of our water consumption, merely constituting a small fraction of the total amount of water each of us actually uses everyday. There is greatly more fresh water invisibly embedded in commodities and particularly in food that we consume in daily life.
Virtual Water refers to the amount of water embedded in the production and transportation of products.
For example, to produce one kilogram of wheat, we need about 1,000 litres of water, i.e. the amount of this kilogram of wheat is 1,000 litres.
Below is a brief illustration on the amount of fresh water consumed for the production of 1 kilogram of beef:
|Resources embedded in the production of 1 kilogram of beef||Water embedded in the production of 1 kilogram of beef|
|(1)||Water for grains - about 6.5kg of grains (e.g. oats)||Producing this volume of feed requires about 15,300 litres of water on average|
|(2)||Water for roughages - about 36kg of roughages (e.g. pasture, dry hay)|
|(3)||Water for drinking||Drinking and servicing require about 155 litres of water on average|
|(4)||Water for servicing|
|Total:||The virtual-water cost for producing 1 kilogram of beef requires about 15,455 litres of water|
|Food||Fresh Water Consumed|
|Chocolate||24,000 Litres / Kilogram|
|Coffee Bean||18,900 Litres / Kilogram|
|Beef||15,455 Litres / Kilogram|
|Chicken||3,900 Litres / Kilogram|
|Rice||3,400 Litres / Kilogram|
|Bread from wheat||1,300 Litres / Kilogram|
|Coffee||1,120 Litres / Kilogram|
|Milk||1,000 Litres / Kilogram|
|Banana||860 Litres / Kilogram|
|Apple||700 Litres / Kilogram|
|Lettuce||130 Litres / Kilogram|
If you wish to learn more about your dietary virtual water, please visit http://www.jcwise.hk/calculator/?lang=e.
Below is a brief illustration on the amount of fresh water consumed to make the products:
|Products||Fresh Water Consumed|
|A car||151,416 Litres|
|A cotton shirt||2,900 Litres|
|A pair of leather shoes||8,000 Litres|
|A pair of jeans||10,000 Litres|
|A smartphone||12,760 Litres|
As responsible citizens of the world living in the global village, we should do what we can to ensure sustainable use of water resources. We can reduce water consumption by making smart choices in purchase and transportation and wisely consuming food/products that require less water for production without wastage.