• Dr. Manoranjan Rajak

Ground water is a precious and the most widely distributed resource of the earth and unlike any other mineral resource, it gets its annual replenishment from the meteoric precipitation. The world’s total water resources are estimated at 1.37 × 108 million ha-m. Of these global water resources about 97.2% is salt water mainly in oceans, and only 2.8% is available as fresh water at any time on the planet earth. Out of this 2.8%, about 2.2% is available as surface water and 0.6% as ground water. Even out of this 2.2% of surface water, 2.15% is fresh water in glaciers and icecaps and only of the order of 0.01% (1.36 × 104 M ha-m) is available in lakes and reservoirs, and 0.0001% in streams; the remaining being in other forms -0.001% as water vapour in atmosphere, and 0.002% as soil moisture in the top 0.6 m. Out of 0.6% of stored ground water, only about 0.3% (41.1 × 104 M ha-m) can be economically extracted with the present drilling technology, the remaining being unavailable as it is situated below a depth of 800 m. Thus, ground water is the largest source of fresh water on the planet excluding the polar icecaps and glaciers. The amount of ground water within 800 m from the ground surface is over 30 times the amount in all fresh water lakes and reservoirs, and about 3000 times the amount in stream channels, at any one time. At present nearly one fifth of all the water used in the world is obtained from ground water resources. Agriculture is the greatest user of water accounting for 80% of all consumption. It takes, roughly speaking, 1000 tons of water to grow one ton of grain and 2000 tons to grow one ton of rice. Animal husbandry and fisheries all require abundant water. Some 15% of world’s crop land is irrigated. The present irrigated area in India is 60 million hectares (M ha) of which about 40% is from ground water.

Ground Water, Resource, Precipitation, Surface Water, Agriculture, Irrigation

"Ground Water Resource its appraisal, Conservation and Planning : A case study of East Champaran District", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.985-997, June-2019, Available :http://www.jetir.org/papers/JETIR1906575.pdf

"Ground Water Resource its appraisal, Conservation and Planning : A case study of East Champaran District", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp985-997, June-2019, Available at : http://www.jetir.org/papers/JETIR1906575.pdf