Water Supply and Demand
Demand for water has been increasing at the global level due to population increases and climate change. Although the world is known as the 'water planet', the water that the humankind could use is limited. The scarcity that grew over thousands of years has now turned into a crisis. It appears that the primary cause for the scarcity of water is not only the population growth but also the distribution of water bodies.
Water Distribution and its Demand
Human activities, and in fact life, depend on the availability of freshwater. Like other natural resources, water is unevenly distributed on the earth, leading to scarcities. Its availability in a given region and the need for water do not coincide with each other. Hence, in some areas, people fight floods all their lives while in others they suffer drought throughout.
In the urban areas, when the water from the tap dries up, the day-to-day life comes to a standstill. There is a definite decline in the health. In industries, the production comes to a stop. Agriculture faces crisis, too, specially in the tailend (downstream) areas.
In some sectors of our economy, water is an input. Irrigation leads the sectors in its demand for water. There are great possibilities for increases in water demand in the domestic and industrial sectors due to population increases. Particularly, in the industrially developed countries, the per capita demand for domestic water is 100 litres per day. When combined with the industrial needs, this per capita increases to 500 litres. In reality, however, 5 to 15 litres of water per day should suffice for an average human being. The modern living is thus based on freshwater and at higher levels of demand.
The largest supply is found in the United States of America. In this country, a large part of the water supplied gets used in the industries. In comparison, the water supply in India is just a quarter of what is being supplied in the United States. Of this water supply in India, a large part is used in agriculture.
Drinking Water Scarcity
Scarcity in drinking water indicates not only to the per capita water availability but also to the difficulties in obtaining the water.
In the developed and industrialised countries, water is supplied largely
through taps. But in most developing countries people have to walk to a source
for a minimum of 2 km. The water needs of three different states/countries of
varying economic development are shown. It seems that the drinking water
scarcity is seen as a consequence of increasing population numbers. This is
however true only to a certain extent. There are indeed several reasons for the
drinking water scarcity. Most important of these are urbanisation and