Water shortages are a real concern in certain parts of the world, particularly in developing areas. About 20 percent of the world’s population lives in places where water is physically scare but a further 25 percent lives in areas that lack the infrastructure to get water from its source -- rivers, aquifers -- to the people whose lives depend on it. And in these and other places, poor water quality, resulting in the spread of diseases like cholera, malaria and typhoid fever, can be as dangerous as no water at all. [source: World Health Organization].
But the total volume of water on planet Earth has not declined and, overall, we are not at risk of running dry. The old yarn about 97 percent of the planet's H2O being the unusable salt variety is just that. Casual observers often don't understand that oceans actually serve as fresh water springs as the sun, sea and evaporation work together to produce about 45,000 gallons (170,344 liters) of rainwater for each of the Earth's inhabitants. The problem is that, in many cases, living communities, farms and reservoirs simply are not developed in areas where that water is easy to access [source: Fishman].