Paul over at Daily Coffee News emailed me asking what I have to say about water and coffee, i.e., "do we have to worry about the water necessary to grow our coffee?" (my words)
The short answer is No. Coffee is no different from any source of demand on water sources. The real question is how large those demands are compared to available (sustainable) supplies.
The long answer is that water needs to be managed into two buckets: water for all of us ("social/environmental water") and water for some of us ("private/economic water").
This starting point means that "we" need to decide how much water to leave in the environment first. That quantity will be lower in poorer places where people want to turn water into money. In richer places, people are willing to pay more for food, landscaping, etc. because they value a healthy environment more than people in poorer places who would rather eat.
Once you decide how much to set aside for social uses, then the rest of the water is devoted to producing private value via drinking, washing, producing goods, growing crops, etc.
Coffee is higher in that priority list in the places where coffee is grown because water for coffee produces more value (income) than, say, water for potatoes or corn. That means that water use in coffee growing regions may remain high in times of water scarcity because farmers prefer to use water for coffee (after drinking and washing) while leaving less for the environment or for growing food crops. That's because they can sell the coffee for money to buy food, rather than growing the food directly. Is this a dumb idea when they can grow food? No. It's better to grow coffee for money in some places and food for money in others.
What's this have to do with footprinting? Not much. As Paul points out, footprinting is not useful in many dimensions.
Bottom Line The footprint is irrelevant compared to social priorities and getting the most value out of the water you have.