What is the Availability of Water
Water is a basic need for human society being required for drinking, bathing, washing, irrigation, industry, cooling, construction work, disposal of sewage and industrial effeuents. Agriculture consumes the maximum amount of water, some 70% of total. Industry requires 26% of water. Domestic and municipal consumption of water accounts for only 1.1%. Because of rising population, increasing urbanization, growing industrialization, rising standards of living, the demand for water is increasing day by day.
Water Availabilty :
The basic source of water availability is rainfall. It occurs in India mostly during monsoon period which lasts for 3-5 months. For the rest of the year, there is no rain. The source of water availability shifts to ground and surface waters.
Dams :
- Dams are barriers constricted across stream to hold back water, raise its level and form reservoirs
- Dams prevent flooding because they store water during rainy season. They are used for generation of electricity (hydroelectric power). Canal system leading from these dams carry large amounts of water year round to great distances of irrigation and navigation.
- Indira Gandhi Canal, for example, has taken water arid areas of Rajasthan (e.g., Jaisalmer, Barmer) bringing greenery all along the way, providing drinking water to thousands of people and irrigation facilities for growing crops like wheat, cotton and mustard.
There are three major problems associated with building of large dams.
- Social Problems :
A large number tribals, peasants and other villagers are displaced. Provision of adequate compensation and rehabilitation measures are not made. - Economic Problem :
A huge amount running into thousands of crores is spent on building large sized dams. They do not generate proportionate benefits. - Environmental Problem :
There is enormous deforestation and loss of biodiversity.
Water Harvesting :
Water harvesting is capturing, collection and storage of rain water and surface run off for filling either small water bodies or recharging ground water so that water continuous to available in nonrainy seasons. Water harvesting has been an age old concept in India. The techniques used are highly region specific.