Deficit rainfall in Karnataka

What is the issue?

Deficit rainfall in the Cauvery catchment areas is likely to cause drought in Karnataka and Tamil Nadu.

What is the status quo of water deficiency in Karnataka?

The areas encompassing the Cauvery catchment, is currently witnessing the worst monsoon in the country.
Earlier this week, four major reservoirs in the Karnataka side of the Cauvery basin had a storage of just 43.18 tmc.
This is barely 40% of total capacity, and is even lesser than the 51 tmc recorded last year (a drought year).
Karnataka has already stated that water will not be released for Kharif crop sowing, this year.
Instead, preference has been given to drinking water needs, estimated to be 30 tmc till the next monsoon.

What is the reason for this water deficit?

Monsoon: Off-shore troughs or depressions (areas of low pressure) in the southern Arabian Sea or the southern Bay of Bengal allow for accumulation of south- west monsoon clouds in south India.
The depressions were off the coast of Maharashtra and Gujarat, and rain-bearing monsoon too migrated there.
Anthropogenic: Large-scale deforestation in the Western Ghats, continued sand mining.
The inability to revive tributaries have led to declining health of the catchment area and river capacity.
Cropping pattern: water-intensive crops such as sugarcane and paddy, which dominate the agrarian landscape.
The proliferation of bore wells, which have had an impact on surface run-off.

What is the status of water sharing with Tamilnadu?

Supreme Court which is hearing appeals by Karnataka, Tamil Nadu and Kerala challenging the 2007 Cauvery Water Disputes Tribunal award.
The share of Cauvery had been determined as 270 tmc to Karnataka and 419 tmc to Tamil Nadu, among others.
In June and July, Karnataka was to release 44 tmc to abide by the award.
Only 7 tmc has been released so far, conflict over water-sharing is bound to rise again.
With lower water release from Karnataka, the main samba crop in Tamil Nadu will be under threat.

Source: The Hindu