An investigation was undertaken to develop a robust solar water purification system for remote areas that have neither suitable potable water nor energy supplies. A study of the challenges of global water supply and existing treatment methods was made to aid the development of the design. Current world water resources are examined regarding climate change, population growth and irrigation and the likely effects are assessed for human health and mortality, potential for conflict, economics and effect on ecosystems. Solutions are posed in the form of development goals, wastewater reuse and desalination. Objectives for the design of effective desalination systems are given. Predictions are also made for various scenarios of response to the looming crisis. The most disturbing is that if there is no response, five billion people are predicted to die rapidly from 2040 on. Action is required now, a global crisis is already happening, and, if not dealt with, water pollution may dramatically decrease the global population in the 21st century with people in less developed regions paying the heaviest prices.