I cannot emphasize how very important the issue of water is. This Truthout article does a good job of summarizing the situation in Bolivia. Here where I live you either have to buy bottled water or boil it--which is of course an expense. Areas of Mexico right now are oppressed by drought and grim pictures of dead and dying cattle are scattered through the news. There are many issues involved in water use. For instance, industrial agriculture (including at times organic vegetable agriculture) suck up the water in water tables depriving small farmers of having it available for their often subsistence crops. The water that industrial agriculture returns to the land is often polluted beyond usefulness. It seeps from larger pools into smaller streams and springs.
You should follow some of the links at the end of the article to learn more about this issue and seek to get involved.