Welcome to Downstream. Water issues affect us all, from the women who spend hours daily fetching water to political battles over international rivers to melting icepack and rising sea levels. We are all downstream.

Worldwide, just under 900 million people lack reliable access to safe water that is free from disease and industrial waste. And forty percent do not have access to adequate sanitation facilities. The result is one of the world's greatest public health crises: 4,500 children die every day from waterborne diseases, more than from HIV-AIDS, malaria, and tuberculosis combined.

A robust economy depends on water. So does a thriving ecosystem. Enter politics, fulcrum of the water issue, weighing the fate of economies against the health of individuals and of the environment as a whole. Balance has been elusive. One fifth of the world's population lives in areas where water is physically scarce, and a quarter of the population faces shortages due to lack of infrastructure.

As you learn about the water issue, consider how you affect those downstream and how those upstream affect you. We hope you'll join the conversation – through comments and questions and by uploading your own perspective on the "Your Stories" feature. Pulitzer Center journalists are in the field now covering the water issue as it unfolds, so check back often for new reports.

The Downstream Gateway was produced by the Pulitzer Center on Crisis Reporting in partnership with National Geographic, PBS NewsHour, the Common Language Project, and the Under-Told Stories Project. Support provided by the Laird Norton Family Foundation and individual donors.

Correction: The original post incorrectly stated that the total deaths from water and sanitation related disease is "more than the toll from HIV/AIDS, malaria, and tuberculosis combined." The statement is true only for children under 14, not adults (see Safer Water, Better Health (WHO) and The Global Fund to Fight AIDS, Tuberculosis and Malaria). Corrections were made August 27, 2010.

Clean Water for All, National Geographic News Series on World<br />
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