If the health risks are not as high as some fear, graywater might gain more acceptance as a water source, and regulations could be eased. Figure 3-14 Cistern installed as part of a graywater reuse system. The intent of the study is to raise public awareness, provide information not available elsewhere regarding graywater quality and its effect on soil, collect data on actual, feasible residential graywater system design and determine the potential graywater has to increase water use efficiency. Rainwater harvesting is collecting rainfall to meet water needs. A rainwater harvesting system concentrates and collects rain falling on house roofs and grounds for direct use and storage.
Water is collected or harvested from concrete patios, driveways and other paved areas.
Also harvested is the flow from the roof and from catchments such as gutters. Houses can be designed to maximize the amount of catchment area, thereby increasing rainwater harvesting possibilities. This additional surface increased the amount of collected annual rainfall by more than 3,700 gallons. Downspouts are located about every 20 feet along the gutter, instead of the more common 40 feet. This ensured that heavy rains were not likely to overflow the gutter and instead would flow to catchments.