Context: A recent study by the Water, Environment, Land and Livelihoods (WELL) Labs highlights a growing groundwater crisis in Karnataka’s Deccan Plateau region.
Relevance of the Topic: Prelims: State of Groundwater crisis in India. Mains: Reasons behind groundwater crisis in India.
Key Findings of the Study
- The researchers examined the gram panchayats in the Upper Arkavathy watershed near Bengaluru, revealing a sharp decline in groundwater levels driven by intensive agricultural practices.
- Average borewell depth increased from 183m (2001-11) to 321m (2011-21).
- 55% of all wells drilled in the Aralumallige sub-watershed have failed.
- 70% of drinking water borewells fail within a decade of construction.
- Water bypasses shallow aquifers due to borewells, reducing groundwater retention.
- Nitrate levels in drinking water frequently cross the safe limit of 50 mg/l.
Reasons behind the Crisis:
- Geographical Limitation: Karnataka’s geography is dominated by basalt and granite formations of the Deccan Plateau. These hard rock aquifers have low porosity, storing water only in narrow fractures and weathered zones. As a result, they offer limited groundwater recharge capacity, especially during dry months. Nearly 99% of the state’s water demand is dependent on these geologically constrained aquifers, making them highly vulnerable to over extraction and long-term depletion.
- Water-intensive Cropping: Vegetable, exotic crops and flower farming demand high water usage. Monsoon relief is temporary; reliance on borewells dominates the rest of the year. While Karnataka banned eucalyptus farming due to the species’ high-water use, its long-term impact on groundwater persists.
- Unregulated Borewell Drilling: While monsoon rains offer seasonal relief, farmers depend on deep borewells for the rest of the year. Borewells drilled into granite bedrock alter the subsurface geology, creating microfractures that fast-track rainwater deep underground. As a result, instead of recharging shallow aquifers, water bypasses them entirely, disrupting the local hydrology and weakening long-term water retention.
- Free Electricity: Electricity is free for farmers leading to over-extraction of groundwater.
- Neglect of Traditional Water Bodies: Lakes and tanks once played a role in recharging groundwater. Encroachment and loss of green cover have made these bodies ineffective.
- Governance and Policy Gaps:
- Poor groundwater data hampers planning and prediction of borewell failures.
- Local governance structures are financially stressed.
- Despite widespread awareness of water scarcity, there have been few efforts to educate farmers on the consequences of water-intensive cropping
- Initiatives like the Jal Jeevan Mission (JJM) focus on infrastructure but not resource sustainability.
Recommendations by Researchers:
- Change cropping patterns: Incentivise less water-intensive farming.
- Compensate farmers for reduced electricity and water use.
- Revive tanks, lakes, and recharge structures.
- Improve local hydrological data and decision-making capacity.
- Integrate resource management with flagship programmes like JJM.
State of Groundwater Crisis in India
- India is the largest extractor of groundwater accounting for 25% of global extraction.
- 61% decline in water levels between 2007 to 2017.
- 60% of irrigated agriculture and 85% of drinking water supplies are dependent on agriculture.
- By 2030, 21 Indian cities are expected to reach ground zero.
Reasons behind Groundwater Crisis in India:
- Introduction of pump sets on a large scale during the Green Revolution.
- Subsidised Electricity
- Flood irrigation method
- Cultivation of Water Intensive crops like rice
- Irregular monsoons and lack of water conservation reduce natural groundwater replenishment.
- Urbanisation and Concretisation
- Non participatory aquifers management
- Unregulated Borewell Drilling
- Lack of focus on groundwater water recharge
- Contamination of surface water bodies
Government Initiatives:
- Atal Bhujal Yojana
- Jal Shakti Abhiyan
- Pradhan Mantri Krishi Sinchai Yojana (PMKSY)- Per Drop More Crop
- Rejuvenation of Ponds, Lakes & Urban Recharge
Strategies Needed:
- Demand Side: Micro irrigation, Crop diversification, separation of feeder lines, use of recycled water.
- Supply side: Construction of check dams, percolation ponds through convergence with MGNREGA.
