[Chris2048]

What does that mean though: "water used"? The only actual use of "water" is an E = mC^2 conversion to raw energy, or a chemical/location change such that it's locked-up/removed from availability permanently.

The water normally continues to exist, so presumably it's some other resource we are using. This may seem pedantic but it's not - raw groundwater, or unprocessed grey water is not potable as in "water a person uses" for drinking, which is a subset of the water a person uses overall (directly in showers etc, or by proxy in bought products, building materials etc).

In each case, water is more of a "carrier" for some other resource or property. If in CA the almonds go through a lot of water (is this due to perspiration? i.e. their cooling mechanism?), the water will still create clouds that I presume increases rainfall elsewhere? In fact, the water now holds more energy (from solar) that might be useful somehow.

Similar comments around "land usage", entirely depends on opportunity loss otherwise.