In Nicaragua, we are experiencing a drought year. The same is true in many other countries. Even where there is no drought, pumping down the water table is the norm. Unfortunately, we tend to not think about our domestic water use as long as water comes out of the pipe.
If you happen to want to get an idea what your use looks like, I found a handy calculator. Just fill in your usage pattern and it shows the totals. You may be suprised.
The calculator is at http://www.csgnetwork.com/waterusagecalc.html