Discuss the availability of water resources in the country and factors that determine its spatial distribution?
India accounts for about 2.45 per cent of the world's surface area and 4 per cent of the world's water resources, while supporting more than 17 per cent of the world's population. This creates a situation of water scarcity relative to the population size.
The total water available from precipitation in a year is about 4,000 cubic km. The availability from surface water and replenishable groundwater is 1,869 cubic km. Out of this, only 60 per cent can be put to beneficial uses, making the total utilisable water resource only 1,122 cubic km.
Surface water resources include rivers, lakes, ponds, and tanks. There are about 10,360 rivers and their tributaries longer than 1.6 km each in the country.
The total replenishable groundwater resources are about 432 cubic km. The level of groundwater utilisation is relatively high in river basins lying in the north-western region and parts of south India. States like Punjab, Haryana, Rajasthan, and Tamil Nadu have very high groundwater utilisation, while states like Chhattisgarh, Odisha, and Kerala utilise only a small proportion of their groundwater potential.
The spatial distribution of water resources is determined by factors such as precipitation patterns, geographical location of river basins, and varying levels of groundwater utilisation across different states.
Explanation
This answer covers both aspects of the question: (1) availability of water resources with specific data from the textbook, and (2) factors determining spatial distribution. Key statistics include India's share of world water resources (4%), total precipitation (4,000 cubic km), utilisable water (1,122 cubic km), and replenishable groundwater (432 cubic km). The spatial distribution is explained through regional variations in groundwater utilisation across states.