I am doing my bit for the California water shortage by avoiding almond milk. I assume there are big numbers assigned to the requirements for dairy milk as well, but it does seem that almonds suck a lot of aquifer water in an area where it could be better used.
According to Capitalism is Freedom, it takes 1.1 gallons of water to produce a single almond, or about which would translate to about 460 gallons of water per pound of almonds. In turn, it takes about two pounds of almonds to make one gallon of Almond Milk, or 920 gallons of water.