Rainfall isn’t enough: scientists call for smarter groundwater management in Telangana
Scientists advocate better annual assessment of groundwater recharge rates to ensure long-term management of groundwater resources in hard rocky terrains such as those found in Telangana.
Although the state receives an average annual rainfall of 960 mm, it contributes only about 10-15% to groundwater recharge due to geological formations, land use and land cover patterns, and irregular rainfall; All of this results in a non-uniform and heterogeneous nutritional scenario.
Scientists from CSIR-Northeast Institute of Science and Technology (NEIST), Jorhat (Assam) and National Geophysical Research Institute (NGRI), Hyderabad, in a joint study, found that the average annual groundwater recharge in Telangana is about 14.3 billion cubic meters (bcm).
Of this, about 11.36 billion cubic meters is attributed to primary recharge from rainfall, while the remaining 3 billion cubic meters comes from secondary sources such as seepage from surface water bodies and return flow from irrigated areas.
The study, led by NEIST Director VM Tiwari, a former NGRI Director, noted that higher recharge rates were observed in northern Telangana due to porous sedimentary formations and north-south rainfall gradient. Mr. Tiwari explained that changes in recharge rates are influenced by anthropogenic implications for irrigation, climate change and fluctuating rainfall patterns.
Interestingly, the study found that despite abundant rainfall for two consecutive years, recharge levels were significantly lower in the second year. Conversely, a dry year followed by favorable rainfall tends to lead to increased recharge.
About 60% of Telangana’s land is used for agriculture, and 90% of this land is devoted to water-intensive crops such as maize, rice and cotton. Between 1997 and 2019, Telangana experienced 10 years of rainfall deficit and nine years of surplus, with deviations exceeding 10% from the long-term annual average. These dry years had a negative impact on groundwater recharge.
The study suggests that despite limited and unchanging storage capacity, such changes significantly impact groundwater availability and agricultural productivity, especially rice cultivation.
In western and southern Telangana, agricultural practices involving deep boreholes have led to overexploitation of groundwater resources. The decline in groundwater levels is due to factors such as subsidized or free electricity to farmers, affordable pump technology and the expansion of cash crop cultivation.
Rice, the dominant crop, consumes disproportionately high amounts of water. The study stated that although farmers are aware of groundwater scarcity, rice cultivation has increased, causing the area irrigated with groundwater to increase 2.5 times in the last three decades.
To ensure sustainability and water security, scientists recommend switching to less water-intensive crops such as millets (ragi, pearl millet, sorghum), grain legumes (lentils, black gram, cowpeas) and rain-fed crops such as oilseeds, pulses and cotton. Crop rotation according to annual water availability is also recommended.
While initiatives such as Mission Kakatiya and improvements in surface water irrigation contribute to better water management, the study highlights the need for a comprehensive groundwater management plan, development regulations and electricity policies to discourage excessive groundwater use.
Scientists Abhilash Kumar Paswan, Ayushi Agarwal, Akarsh Asoka, Ramaswamy Rangarajan and Shakeel Ahmed also participated in the research.
It was published – 24 October 2025 18:01 IST
