What about water? It is easy to take this basic building block of life for granted. However, water is a surprisingly limited commodity. Over the next 30 years, the global water supply is in danger of drying up. The world population is projected to reach nine billion by 2050. Not only will these people need water to drink and bathe with also a massive amount of water must be used to grow additional food. The most rapid growth will be in developing nations, whose water supplies are already under stress.