There are further limits on utilizable quantities of water owing to uneven distribution overtime and space. Water is vital for realising the full potential of the agriculture sector and the country’s development. In some areas, it is abundantly found while in other areas like Thar Desert it is scarcely available. Similarly, it is available in plenty in rainy season, while in dry season it becomes scarce.
One of the important uses of water in our country is for irrigation. Besides, water is required in large amounts for industrial and domestic consumption. The average annual water availability of the country is assessed as 1869 billion cubic metre (Bom) of this total utilizable water resource is assessed as 1123 Bern and 433 Bern replenishable ground water resources. The Ministry of Water Resources lays down policies and programmes for development and regulation of the country’s water resources.
The National Water Policy adopted in September 1987 and updated in 1998 stresses that water is a prime natural resource, a basic human need and a precious national asset. Average run-off in the river system of the country has been assessed as 1869 km.
Of this, the utilisable portion is estimated as about 690 km3. There is substantial replenishable ground water potential in India estimated at 432 km3. The per capita availability of water has reduced from about 5277 m3 in the year 1951 to the present level of 1869 m3. There is all probability that in future situation may aggravate due to the growing water scarcity in the river basins.
I. Annual rainfall (2005) – 1208 mm
II. Major river basin – 12 (catchment area > 20, 000 sq. km) – 253 M. ha
III. Medium River Basins –46 (catchment area < 20, 000 sq. km) – 24.6 M. ha
IV. Average annual Precipitation – 4000BCM
V. Average Precipitation during Monsoon (Jun-Sept – 3000 BCM
VI. Natural Runoff – 1986.5 BCM
VII. Estimated utilizable surface water resources – 690 BCM
VIII. Total utilizable ground water resources – 433 BCM
IX. Total annual utilizable water resources – 1123 BCM
Note: BCM means billion cubic metres