Turning off the tap hardly matters

I came across some interesting figures on water use for food production today. I'd already known that most water use goes to agriculture. The numbers for water use are roughly 70% agriculture, 20% industry, and 10% for domestic use.

Some agricultural uses take much more water than others. A pound of beef, for example, takes about 4000 litres of water (I couldn't find any universally accepted figures. Click on the image below for a rough idea of water required for different foods).

This is because not only do you have to give the cow water to drink for years, but you also have to water the feed that the cow eats. I'm sure there are other water needs as well.

As humans, we tend to focus on the things we do personally with effects directly visible in our lives. So, if people decide they ought to do something to reduce water usage, they may decide to focus on something immediately present, like turning off the tap.

Eating beans instead of beef would be infinitely more effective; a vegetarian could leave a tap running for hours, and still use less water than your typical meat eater. But since we don't directly see it, people often focus on the much smaller amounts of water usage that they directly control in their houses.

Another under-appreciated fact is that the 70% of water used by agriculture and the 20% used by industry are ultimately used to make things used by us. So, in an indirect sense, it's really our water usage. This applies to pollution and resource usage more generally.

Which is why it's nonsensical when some people assume that the solution to our environmental problems lies with greedy industries*, and if they cleaned up their act, everything would be fine. Ultimately, the problem lies with all of us who consume the products of industrial society.

This is a chart of estimated household usage, for comparison. Note how slight the amounts are compared to those used to produce our foods:

* This is not to say that greedy industries aren't part of the problem. Industry lobbying to mislead the public and preserve the status quo has been quite harmful. The industry financed propaganda campaign against climate change in the US is a prime example.