Substitute for water purification plants and pipes, or trucked in water with:
- Solar water pasteurization.
Build a simple solar cooker into the side of each hut, using the same building materials as the rest of the unit (reflective insulation boards). Primary use of the cooker is heater water to 160+F for the full day to sterlize it (and the container). Remaining issues around reliable indicators that the water has been fully treated are being worked on by a variety of groups.
I do not suggest cooking on the solar cooker as a core technology. General field reports seem to indicate solar cooking doesn't go over terribly well in many areas.
- $10 or less per household for the solar cooker.