Plunging reservoir levels
The deficit of pre-monsoon rainfall led to a severe water crisis in April-May. According to the Central Water Commission’s May 9 bulletin, in Karnataka’s Krishnaraja Sagara (KR Sagar) and Kabini reservoirs, the live storage fell to a 30-year average low. KR Sagar had 10 TMC last year, which plunged to 7.2 TMC now.
Similarly, Kabini had 4.6 TMC average live storage last year. It’s down to 3.7 TMC this year. The available live storage of Tamil Nadu’s reservoirs, Mettur and Bhavanisagar, is also lower than their 30-year average.
“If pre-monsoon showers don’t get activated in the coming days, water level in KR Sagar will fall to its lowest since its inception,” said Venkatesh R L, Chief Engineer, Irrigation (South) Zone at the Cauvery Neeravari Nigama.
The KR Sagar Dam reached its lowest level on June 13, 2013, at 62.80 feet. Its level as on May 9 was around 79 feet, compared to last year’s 85 feet. Both Karnataka and Tamil Nadu are left with water only for drinking and domestic use till the southwest monsoon sets in.
“Even if the Southwest monsoon is normal in June-July, because of acute moisture deficit in the soil due to the severe drought, there may not be enough runoff to the catchment of the Cauvery basin,” said K E S Mahesha, managing director of the Cauvery Neeravari Nigama.
Climate change
Experts attribute several climatic factors to the excessive heating of peninsular India, which include weakening of the land-ocean temperature gradient due to global warming. Globally as well, each month is setting a new all-time record. The last 10 months since June 2023 have been the hottest on record because of El Nino. The Indian Ocean has one of the world’s fastest-rising sea surface temperatures.
“There are several factors involved in the current peninsular drought, including the strengthening of El Nino, which contributed to the above normal temperatures coupled with a long spell of marine heat wave in the Indian Ocean,” said Dr Vimal Mishra, Professor, Civil Engineering and Earth Sciences, at Indian Institute of Technology, Gandhinagar.
“Climate change induced the late onset of a strong Southwest monsoon and the change of cropping pattern towards water-intensive paddy and cash crops like cotton,” said Ramanjaneyulu.
