In the Murray Darling Basin the CSIRO has estimated that the dairy industry uses about 9 times more water than the combined use of the fruit and vegetable industries, and far more than either cotton or rice.
The overallocation of Murray Darling water goes back over a decade.
How do you irrigate a high energy alfalfa paddock for dairy fodder? Can you use a drip system? No, the method of irrigation is commonly called flood or pivot irrigation. It is not only water intensive, but prone to high evaporation losses.
The 2004 CSIRO report mentioned earlier, used sophisticated satellite image processing to estimate pasture irrigation levels. It estimated that the dairy industry increased its water take from 2,400 billion litres in 1995 to 4,200 billion litres in 2000. This is a staggering increase for Murray water.
To put this 4,200 billion litre figure in perspective, compare it with the 2,300 billion litres used by all the towns and cities in Australia.
The amount of water used to make a litre of milk is between 320 and 1000 litres. The low number just counts water pulled out of rivers and lakes. This water is called extracted water. The high figure includes all the water embodied in dairy cattle feed. This embodied water figure is not the total rainfall in the area, but only the part of the rain embodied in the plant. Yes, scientists really can work out such numbers.
Soymilk requires about half the embodied water of dairy milk. Fullfat soymilk has a similar amount of fat to normal milk, but 60% of dairy milk fat is saturated, compared with just 12% of the fat in soymilk. Unlike dairy milk, brands of soymilk vary significantly in taste and texture. It’s easy to find the ones you like the most.