Important water scarcity terms
This is the absence of (lack of) water, or inadequate safe water in any geographic area for human, animal and environmental use. In many places, there may be water not far off, but there is simple very little resources (money and ability) to bring it home, and makes it very expensive. This can be called economic water scarcity. On the other hand, there could be physical scarcity, which means there is no water at all (or just not enough).
This is usually confused with water scarcity. In a way, water stress is the result of scarcity, in the sense that the demand for water far exceeds the available amount. This causes deterioration of fresh water and results in drought.
This is water that is considered safe enough for human consumption with little risk of short and long term harm. It is usually known as ‘wholesome’ water. Water can be called wholesome only after experts test and confirm that the water complies with specific standards set by the authorities.
Irrigation is the application of water to crop farms to provide the plants with water to grow. Irrigation can increase yields of most crops by 100 to 400%. Farmers who switch from surface irrigation to localized irrigation can cut their water use by 30 to 60%. FAO
These are diseases which are transmitted by drinking contaminated water. Examples of such diseases include Typhoid fever, Malaria, Hepatitis A, Cholera, Bacillary Dysentery/Shigellosis.
This is water that has a higher salt content, but not as high as sea water. This kind of water is usually found where fresh water meets sea water (estuaries, deltas and mangrove swamps). Usually brackish water has less living organisms in it.
Beneath the earth's surface are rocks. some of these rocks are porous and permeable and allow water and gsses to flow through them freely. These water-bearing rocks are called aquifers. Water from aquifers tend to be very pure if not exposed to soil pollution.