The World Health Organization says that it's World Water Day so how about reading:

10 facts about water scarcity

A lack of water to meet daily needs is a reality for many people around the world and has serious health consequences. Globally, water scarcity already affects four out of every 10 people. The situation is getting worse due to population growth, urbanization and increased domestic and industrial water use.

The fact is that providing access to safe drinking water and proper sanitation are among the highest impact and most achievable projects we could take on if we're serious about alleviating the suffering of the world's poorest. To get you started here are links to Changing Lives Through Water and Sanitation at World Vision and Blood:Water Mission, an organization founded by the members of Jars of Clay that exists to promote clean blood and clean water efforts in Africa. How about some more suggestions in the comments block?