Water resources in the country: As per the assessment done by CWC in the year 1993, the river basinwise average annual water availability in the country is 1869 billion cubic meters (BCM). It is estimated that owing to topographic, hydrological and other constraints, the utilizable water with conventional approach is 1137 BCM which comprises of 690 BCM of surface water and 447 BCM of replenishable ground water resources. Further, it has been estimated in the year 2009 by CWC that about 450 BCM of surface water is being utilized for various purposes.

Reassessment Brief Note, 1993 

Draft Reassessment Water Availability Main Report, 2018