NEXT time you throw back a beer or sit down to a cup of coffee consider this: you've just consumed up to 140 litres of water — enough to fill a bath. Most people view personal water consumption in terms of running taps or toilet flushing.

But these are trifling compared to the surface, ground, soil water and rainfall it takes to produce everything we consume. For instance, it takes an estimated 8000 litres of water to produce a single pair of leather shoes.

Eat a kilogram of steak and you are responsible for using up to 16,000 litres of water. A bag of potato chips: 185 litres. An apple: about 70 litres.

A global study of the "water footprints of nations", by international water experts Arjen Hoekstra and A. K. Chapagain, found that Australian households held the world's worst record for water consumption, despite our industry and farmers being relatively efficient.

Published in January in the journal Water Resources Management, the study found that Australian households had a "water footprint" equivalent to 341,000 litres per person per year.