Water is a
precious natural resource vital, for sustaining all life on
the earth. It is in a continuous circulatory movement between
land, ocean and atmosphere - the hydrological cycle. It is not
uniformly distributed in time and space. Due to its multiple
benefits and the problems created by its excesses, shortages
and quality deterioration, water as a resource requires
Fig: Hydrological Cycle
Source : Irrigation Theory and Practices: Michael
Sustainable development demands that we should use our
precious water resources efficiently and effectively. This
will have to include forward planning and action, which can
specifically address; both, the existing and emerging human
and environment problems. On a global scale, total quantity of
water available is about 1600 million cubic km. The
hydrological cycle moves enormous quantities of water about
the globe. However, much of the world's water has little
potential for human use.
The distribution of water on earth in percentage is estimated as
Ground water 0.62
Fresh Water lakes 0.009
Inland sea and salt lakes 0.008
Hence, the fresh
water resources of an area comprise mainly of:
The Water Budget:
India has sizable resources of water and a large cultivable land
but also a large and growing population to feed. Erratic
distribution of rainfall in time and space leads to conditions of
floods and droughts which may sometimes occur in the same region
in the same year. India has about 16% of the world population as
compared to only 4% of average annual runoff in the rivers.
LAND AND WATER RESOURCES OF
Flood Prone Area
Ultimate Irrigation Potential
Total Cultivable Land Area
Net Irrigated Area
Natural Runoff (Surface Water and Ground
Utilizable Surface Water Potential
Available Groundwater resource for Irrigation
Net Utilizable Groundwater resource for
329 million ha.
40 million ha.
140 million ha.
184 million ha.
50 million ha.
1869 Cubic km
690 Cubic km.
432 Cubic km.
361 Cubic km.
325 Cubic km.
Water Resources, Government of India