Context: The Central Water Commission (CWC) in its study titled 'Assessment of Water Resources of India 2024' estimated that India's average annual water availability, between 1985 and 2023, stood at 2,115.95 billion cubic meters (BCM).

Key points from the CWC Study

• Basis of the Water Availability Figure: The estimate is based on annual net-runoff, which incorporates precipitation, evapotranspiration, land use, land cover, and soil datasets.

• The water availability was calculated for all river basins in India, excluding the Indus basin's three western tributaries (Indus, Jhelum, and Chenab).

Water Availability Across Regions

• The top three basins with the highest water availability are:

• Brahmaputra Basin: 592.32 BCM

• Ganga Basin: 581.75 BCM

• Godavari Basin: 129.17 BCM

• The bottom three basins with the least water availability are:

• Sabarmati Basin: 9.87 BCM

• Pennar Basin: 10.42 BCM

• Mahi Basin: 13.03 BCM

• Comparison with Previous Assessments: The 2024 figure of 2,115.95 BCM is higher than the 2019 estimate of 1,999.2 BCM, which was based on data from 1985 to 2015.

• Earlier assessments (since 1901) consistently found India's water availability to be below 2,000 BCM.

• Reasons for the Higher Figure in 2024: The updated assessment includes water contributions from Bhutan to the Brahmaputra basin, which were not accounted for in previous studies.

• The full contribution of Nepal to the Ganga basin is also considered in this assessment, whereas only partial inclusion was made in 2019.

Usability of Water

• The CWC's water availability figures do not refer to utilizable water.

• For example, in 2019, out of the estimated 1,999.2 BCM of water, only about 690 BCM was considered utilizable.

• Smaller river basins tend to have a higher proportion of utilizable water, except in basins like West Flowing Rivers and Sabarmati.

• The Brahmaputra basin has a relatively low proportion of utilisable water.

Water Stress and Scarcity:

• According to the Falkenmark Indicator:

• Water Stress: If per capita water availability is below 1,700 cubic meters.

• Water Scarcity: If it is below 1,000 cubic meters.

• Absolute Water Scarcity: If it is below 500 cubic meters.

About Central Water Commission

• Established in: 1945

• Central Water Commission is a premier Technical Organisation in the country in the field of water resources.

• It is charged with the general responsibilities of initiating, coordinating and furthering, in consultation with the State Governments concerned, schemes for control, conservation and utilization of water resources throughout the country, for purpose of Flood Control, Irrigation, Navigation, Drinking Water Supply and Water Power Development.