Showing posts with label Drinking water. Show all posts
Showing posts with label Drinking water. Show all posts

Thursday, December 9, 2010

Water Resources in India

India is endowed with a rich and vast diversity of natural resources, water being one of them. Its development and management plays a vital role in agriculture production. Integrated water management is vital for poverty reduction, environmental sustenance and sustainable economic development. National Water Policy (2002) envisages that the water resources of the country should be developed and managed in an integrated manner.

Water is food and fire is the eater of the food.
Fire is established in water and
Water is established in fire


-Taittiriya Upanishad 3.8






icon  General Facts


World oceans cover about three fourth of earth’s surface. According to the UN estimates, the total amount of water on earth is about 1400 million cubic kilometre  which is enough to cover the earth with a layer of 3000 metres depth. 

http://www.unep.org/dewa/vitalwater/jpg/0241-daming-capacity-EN.jpg However the fresh water constitutes a very small proportion of this enormous quantity. About 2.7 per cent of the total water available on the earth is fresh water of which about 75.2 per cent lies frozen in polar regions and another 22.6 per cent is present as ground water. The rest is available in lakes, rivers, atmosphere, moisture, soil and vegetation. What is effectively available for consumption and other uses is a small proportion of the quantity available in rivers, lakes and ground water. The crisis about water resources development and management thus arises because most of the water is not available for use and secondly it is characterized by its highly uneven spatial distribution. Accordingly, the importance of water has been recognised and greater emphasis is being laid on its economic use and better management.

Water on the earth is in motion through the hydrological cycle. The utilisation of water for most of the users i.e. human, animal or plant involve movement of water. The dynamic and renewable nature of the water resources and the recurrent need for its utilisation requires that water resources are measured in terms of its flow rates. Thus water resources have two facets. The dynamic resource, measured as flow is more relevant for most of developmental needs. The static or fixed nature of the reserve, involving the quantity of water, the length of area of the water bodies is also relevant for some activities like pisciculture, navigation etc. Both these aspects are discussed below.



Irrigation World

Analysing the country-wise geographical area, arable land and irrigated area in the World, it is found that among the continents largest geographical area lies in the Africa which is about 23 per cent of the world geographic area. However, Asia (excluding erstwhile countries of USSR) with only 21 per cent of world geographical area has about 32 per cent of world’s arable land followed by North Central America having about 20 per cent of World’s arable land. Africa has only 12 per cent of world’s arable land. It has been seen that irrigated area in the World as about 18.5 per cent of the arable land in 1994. In 1989, 63 per cent of world’s irrigated area was in Asia, whereas in 1994 this percentage has gone upto 64 per cent. Also 37 per cent of arable land of Asia was irrigated in 1994. 


Among Asian countries, India has the largest arable land, which is close to 39 per cent of Asia’s arable land. Only United States of America has more arable land than India.


icon  Ground Water Exploration



Ground water exploration aided by drilling is one of the major activities of the Board with an objective to discover aquifers in different hydrogeological conditions and determination of hydraulic parameters. Large-scale sub-surface exploration programme for ground water was initiated during 1954. In the initial years, exploratory drilling activities were confined to alluvial tracts in major river basins and sub mountainous bouldary tracts of Himalayan foothills. In mid eighties, CGWB added 26 new DTH drilling rigs in its fleet with which the exploratory drilling in hard rock regions gained momentum. The major thrust of exploratory drilling programme in nineties was in areas underlain by hard rock. Another important development in first half of nineties was introduction of open hole drilling technology in India. CGWB acquired seven percussion drilling rigs for exploratory drilling in bouldary/ semi-consolidated formations in Himalyan foothills from Jammu & Kashmir in  north west to Arunachal Pradesh in north east. These exploration programmes formed the background of scientific evaluation of the water bearing properties of various rock formations. 

More than 27,500 wells have been drilled by Central Ground Water Board throughout the country. High yielding wells were drilled under ground water exploration programme in water deficient areas in the country, including  tribal and drought prone areas. Most of these high yielding wells have been handed over to the respective State Governments for public water supply. Board had also come forward in disaster mitigation activities during Latur earthquake during 1993, Bhuj earthquake during 2001, Super cyclone in Orissa during 2000 and Tsunami hit coastal belt of Tamil Nadu & Kerala and Andaman & Nicobar Islands during 2004 by way of construction of tube wells for water supply. 

icon  Water Bodies


Inland Water resources of the country are classified as rivers and canals; reservoirs; tanks & ponds; beels, oxbow lakes, derelict water; and brackish water. Other than rivers and canals, total water bodies cover all area of about 7 M.Ha. Of the fivers and canals, Uttar Pradesh occupies the First place with the total length of rivers and canals as 31.2 thousand km, which is about 17 percent of the total length of rivers and canals in the country. Other states following Uttar Pradesh are Jammu & Kashmir and Madhya Pradesh. Among the remaining forms of the inland water resources, tanks and ponds have maximum area (2.9 M.Ha.) followed by reservoirs (2.1 M.Ha.).

Most of the area under tanks and ponds lies in Southern States of Andhra Pradesh, Karnataka and Tamil Nadu. These states along with West Bengal, Rajasthan and Uttar Pradesh, account for 62 percent of total area under tanks and ponds in the country. As far as reservoirs are concerned, major states like Andhra Pradesh, Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Orissa, Rajasman and Uttar Pradesh account for larger portion of area under reservoirs. More than 77 percent of area under beels, oxbow, lakes and derelict water lies in the states of Orissa, Uttar Pradesh and Assam. Orissa ranks first as regards the total area of brackish water and is followed by Gujarat, Kerala and West Bengal. The total area of inland water resources is, thus, unevenly distributed over the country with five states namely Orissa, Andhra Pradesh, Gujarat, Karnataka and West Bengal accounting for more than half of the country's inland water bodies.

icon  Water in Indian Constitution


India is union of States. The constitutional provisions in respect of allocation of responsibilities between the State and Centre fall into three categories: The Union List (List-I), the State List (List-II) and the Concurrent List (List-III). Article 246 of the Constitution deals with subject matter of laws to be made by the Parliament and by Legislature of the States. As most of the rivers in the country are inter-State, the regulation and development of waters of these rivers, is a source of inter-State differences and disputes. In the Constitution, water is a matter included in Entry 17 of List-II i.e. State List. This entry is subject to the provision of Entry 56 of List-I i.e. Union List.