Goedjn wrote:


at annual rainfall, because if you use more water than
falls, then eventually you're likely to run out.

In the west, aquifers are rarely (if ever) ground replenished fed from
local precipitation...local surface replenishment is probably only a
small fraction of the total replenishment.

All the more reason not to be depending on it.

That's precisely the point--in most of the west the underground aquifers
are not dependent on surface precipitation. That doesn't _necessarily_
mean it is an unreliable source, just that it isn't surface replenished.