Karnataka’s angst and anger over a Supreme Court (SC) order to release water of the Cauvery river to neighbour Tamil Nadu is rooted in the failure of the monsoon in the state, a hidden variation of India’s statistically normal monsoon.
Reservoirs in the Cauvery catchment are half as full as they should be, 42 per cent of minor irrigation tanks are dry statewide and 90 per cent of Karnataka’s taluks — subdivisions of districts — recorded deficit rainfall in August. The water in Karnataka’s reservoirs must now be shared between farmers in Karnataka and Tamil Nadu and meet Karnataka’s own drinking water needs.
Overall, the state was 16 per cent short of normal rainfall between June 1, 2016, and September 5, 2016, according to data from the Karnataka State Natural Disaster Monitoring Centre (KSNDMC).
The Meteorological Department classifies this as a “normal” deficit, but rainfall was intermittent and uncertain through the monsoons.
After two consecutive droughts, India received normal rainfall — 2 per cent less than the 100-year average — by the end of August 2016, but within that normality, more than a third of the country is short of rain, according to India Meteorological Department (IMD) data.
Protests erupted in parts of Mysore-Mandya region on September 6 following the SC order and the government’s decision to release water to Tamil Nadu. The government has sought a modification of the order.
In August, Karnataka’s four zones — south and north interior, the southern Malnad region and the coast — recorded a 39 per cent deficit in rainfall.
The Malnad region, which is critical for the Cauvery’s catchment area, received 977 mm in August, against the normal 1,369 mm, a 29 per cent deficit.
The situation worsened over the monsoon: 101 of 176 talukas in Karnataka recorded deficit rainfall (-20 to -59 per cent), while 55 talukas recorded scanty rainfall (-60 to -99 per cent) in August 2016.
The August rains are critical to the sowing of important crops, such as paddy, ragi, maize and sugarcane. With no more than four weeks left for the end of southwest monsoon, farmers are struggling.
Water levels of reservoirs in the Cauvery catchment area, including the Krishna Raja Sagara (KRS) dam in Mandya district, Kabini in Mysore, Harangi in Kodagu and Hemavathi in Hassan were less than normal (based on a 15-year average) and less than the levels in 2015, according to KSNDMC data on September 3.
Of 3,598 minor irrigation tanks in the state, 42 per cent are dry and no more than 12 per cent of tanks are more than half full, according to KSNDMC data.
The water level at KRS on September 3 was 17.96 tmcft (thousand million cubic feet), against its capacity of 49.45 tmcft, lower than last year’s level over the same period (25.30 tmcft). KRS is normally full by this time.
The SC’s order to release 15,000 cusecs to Tamil Nadu over 10 days would mean the state has to release 13.6 tmcft of water, 24 per cent of the water now available in the Cauvery basin reservoirs.
The situation in nine other reservoirs statewide was no better, except for Krishna Basin reservoir’s Almatti dam, in northern Karnataka, which is full; Ghataprabha dam, which is at 87 per cent of its capacity; and Narayanapuram dam which is at 96 per cent of its capacity.
This could worsen Karnataka’s drinking water situation in the coming days. Farmers’ representatives argued that their livelihoods are at stake if Karnataka releases more water.