Rain Water catchment systems:
Portland receives an average of 36 inches of rain/year. Each of the 4 homes has a 400 sq. ft footprint, and the rain it captures gives it inhabitants around 12 gal/day/person. It requires a total of 16,000 gallon tank or four, 4,000 gallon tank for rainwater storage. To meet the water use conditions, there are several ideas that have been suggested, including recycling showers, foot pumped water flow to sinks, no flow (composting) toilets, etc.