Although covering some 70% of the Earth's surface, most water is saline. Freshwater is available in almost all populated areas of the earth, although it may be expensive and the supply may not always be sustainable. Sources where water may be obtained include:
- ground sources such as groundwater, hyporheic zones and aquifers.
- precipitation which includes rain, hail, snow, fog, etc.
- surface water such as rivers, streams, glaciers
- biological sources such as plants (See Gathering water from plants)
- the sea through desalination
- Water supply network[1]
In practice
The classic solution with minimal life-style changes for obtaining water in a autonomous house is by using a well. Once drilled, a well-foot requires substantial power. However, advanced well-foots can reduce power usage by twofold or more from older models. Well water can be contaminated in some areas. The sono arsenic filter eliminates unhealthy arsenic in well water.
However drilling a well is an uncertain activity, with aquifers depleted in some areas. It can also be expensive.
In regions with sufficient rainfall, it is often more economical to design a building to use rain, with supplementary water deliveries in a drought. Rain water makes excellent soft washwater, but needs antibacterial treatment. If used for drinking, mineral supplements or mineralization is necessary.[2]
Notes and references
See also
- Sewage system: most systems (in the developed world) use a combined sewage/potable water system