Water Availability And Usage

India has around 4% of the world’s water resources, with a total water availability of about 4000 cubic km from precipitation annually.

From this, a sum of 1,869 cubic km is available from surface water and replenishable groundwater, but only 60% of this can be put to beneficial use, totalling 1,122 cubic km in utilisable water resources.

Surface Water Resources

Surface water is primarily sourced from rivers, lakes, ponds, and tanks. There are about 10,360 rivers and tributaries in India, each longer than 1.6 km.

The mean annual flow across all river basins is 1,869 cubic km, yet due to various constraints only 690 cubic km (or 32%) of this surface water can be utilised.

The rivers Ganga, Brahmaputra, and Indus have extensive catchment areas and, given the relatively high precipitation in these catchments, they contribute significantly to India’s surface water resources, despite covering only about a third of India’s area.