Water Resources

Sources of Freshwater in India: • India receives about 4,000 billion cubic metres (BCM) of precipitation annually — but only about 1,869 BCM is the average annual flow in rivers and groundwater; of this, only about 1,123 BCM is usable. • India is a 'water-stressed' country — there is substantial regional and seasonal variation in water availability. 1. Precipitation (Rainfall and Snow): • India's rainfall varies enormously — from over 1,000 cm in Cherrapunji (Meghalaya) to under 10 cm in the Thar Desert (Jaisalmer). • The south-west monsoon (June–September) brings about 75% of India's annual rainfall. • North-east monsoon: Brings winter rainfall to Tamil Nadu and southeastern coasts. 2. Rivers: • Himalayan Rivers (perennial): Ganga, Brahmaputra, Indus — fed by both monsoon rainfall and glacial meltwater. Flow throughout the year. • Peninsular Rivers (non-perennial/seasonal): Godavari, Krishna, Mahanadi, Cauvery, Narmada, Tapti — depend primarily on monsoon rainfall; some dry up in summer. 3. Groundwater: • Groundwater is recharged by rainfall percolating through soil. • India has the world's largest groundwater extraction — about 250 BCM per year. • The Indo-Gangetic Plain has the largest aquifer in Asia. • Over-extraction is causing rapid groundwater depletion — especially in Punjab, Haryana, UP, Rajasthan. 4. Lakes: • Natural lakes — Dal Lake (Kashmir), Chilika (Odisha — largest brackish water lake), Wular Lake (Kashmir). • Man-made reservoirs behind dams — Gobind Sagar (Bhakra dam), Nagarjuna Sagar, Sardar Sarovar. Distribution — Uneven: • Water-abundant regions: Northeast India (Brahmaputra basin), Western Ghats coast, Ganga delta. • Water-scarce regions: Rajasthan, Gujarat, Deccan plateau, south Tamil Nadu, Bundelkhand. • Seasonal scarcity: Most of India has monsoon rainfall — so water is abundant July–October and scarce March–June.

Major Uses of Water in India: 1. Agriculture (Largest user — ~90% of water use): • Irrigation is the dominant water use — paddy, wheat, sugarcane, and cotton require large amounts of water. • Flood irrigation (traditional method) is highly inefficient — much water evaporates or runs off. 2. Domestic/Municipal use (~6%): • Drinking water, cooking, bathing, sanitation. • Urban demand is growing rapidly. • Many Indian cities face daily water shortages. 3. Industrial use (~4%): • Cooling (thermal power plants), processing (paper, steel, textiles), steam generation. • Industrial water demand is growing. The Water Crisis in India: 1. Groundwater depletion: • Punjab, Haryana, and parts of UP are 'over-exploited' — extraction exceeds natural recharge. • Green Revolution's intensification of paddy cultivation in Punjab (not naturally suited for it) has drained aquifers. • Millions of borewells — pumping groundwater faster than it can recharge. 2. Deteriorating water quality: • Groundwater contaminated by: Fluoride (Rajasthan), Arsenic (West Bengal, Bihar), nitrates (from fertilisers), industrial effluents. • River pollution: Most of India's rivers are severely polluted by sewage and industrial effluent — Yamuna, Ganga (despite the Namami Gange programme). 3. Unequal access: • Rural populations often lack safe drinking water access. • Jal Jeevan Mission: Government target to provide piped water to every rural household by 2024. Water Management Strategies: 1. Rainwater harvesting: • Collecting and storing rainwater — rooftop harvesting, ponds, johads (traditional Rajasthan tanks), check dams. • Traditional water conservation systems: Kul (Himachal Pradesh), Baoli (stepwells), Taanka (Rajasthan), Ahar-Pyne (Bihar). 2. Drip and sprinkler irrigation: • Much more efficient than flood irrigation — reduces water use by 30–50%. 3. Watershed development: • Integrated management of a drainage basin — reducing runoff, increasing groundwater recharge. 4. Interlinking of rivers: • Controversial mega-project to link water-surplus rivers to water-deficit basins. • Challenges: Environmental, displacement, inter-state disputes. 5. Regulation of groundwater extraction: • Pricing, licensing, awareness. 6. Treated wastewater reuse: • Using treated sewage for irrigation.

Inter-State River Water Disputes: • Rivers in India cross state boundaries — the distribution of their waters between states is a major source of political conflict. • Article 262 of the Constitution allows Parliament to adjudicate inter-state water disputes. • The Inter-State River Water Disputes Act (1956) provides for tribunals to adjudicate disputes. Major River Water Disputes: 1. Cauvery dispute: Tamil Nadu, Karnataka, Kerala, Puducherry. 2. Krishna dispute: Maharashtra, Karnataka, Andhra Pradesh, Telangana. 3. Narmada dispute: Gujarat, Madhya Pradesh, Maharashtra, Rajasthan. 4. Sutlej-Yamuna Link (SYL): Punjab and Haryana. 5. Mahanadi dispute: Odisha and Chhattisgarh. Cauvery Water Dispute (Detailed): River: The Cauvery (Kaveri) originates in Coorg (Karnataka) and flows through Tamil Nadu before emptying into the Bay of Bengal. Parties: Karnataka (wants more water for Bengaluru, Mysuru, and agriculture) vs. Tamil Nadu (claims historical right, needs water for Cauvery delta paddy farming). History: • An agreement was reached in 1892 and 1924 between Madras Presidency and Mysore — allocating water between them. • After independence, Karnataka argued the old agreement was unfair and wanted more water for development. • Tamil Nadu argued its prior rights must be respected. Cauvery Water Disputes Tribunal: • Set up in 1990; gave its final award in 2007. • Allocated: Karnataka 270 TMC, Tamil Nadu 419 TMC, Kerala 30 TMC, Puducherry 7 TMC. • Karnataka challenged the award; Supreme Court modified it in 2018 — slightly increasing Karnataka's share (giving Bengaluru additional allocation for drinking water). Ongoing Tensions: • Periods of drought trigger acute crisis — Karnataka reduces releases; Tamil Nadu farmers protest; communal tensions flare between Kannada and Tamil communities. • 2016 crisis: Karnataka's failure to release water ordered by Supreme Court led to violence in Bengaluru; Tamil Nadu farmers' protests. Lesson: • The Cauvery dispute shows that river water allocation is not merely technical — it is deeply political, tied to agricultural livelihoods, and inflamed by regional identity politics.