Quick Water Question

[bigpaul]

I think its just a general rule of thumb.
In arid areas you would need twice that at least.

To be honest 2 liters is a very small amount of water when you take into account the water you need for cooking things like rice and pasta.
Then you need to wash plates and a weekly wash of yourself.

2 litres is JUST for drinking per person per day, it does NOT included washing or cooking.