Water is essential to all life. It covers about 71% of the Earth's surface, but freshwater — which humans, animals, and plants can use — forms only about 2.5% of total water. Of this, most is locked in ice caps and glaciers. Only about 0.3% of all freshwater is accessible in rivers and lakes.
Water Scarcity and Its Causes
- India receives adequate rainfall overall, but water scarcity is a real problem because:
- Uneven distribution: Some regions (like Meghalaya, Assam) get over 2,000 mm of rain; others (like western Rajasthan) get under 100 mm.
- Seasonal: Most of India's rain falls in a 3-4 month monsoon period, but demand is year-round.
- Over-extraction: Rapid population growth, urbanisation, and industrialisation increase water demand faster than supply.
- Water pollution: Rivers and groundwater are polluted by industrial effluents, agricultural chemicals, and untreated sewage.
Multi-Purpose River Projects
- India has built large dams and reservoirs (multi-purpose river projects) to:
- Store monsoon water for year-round use (irrigation, drinking).
- Generate hydroelectric power.
- Control floods.
- Facilitate navigation.
- Provide water for industrial use.
- Major dams:
- Bhakra Nangal Dam (Sutlej river, Punjab/Himachal Pradesh) — the largest dam in India.
- Damodar Valley Project (Damodar river, Jharkhand/West Bengal) — modelled on the US Tennessee Valley Authority.
- Nagarjuna Sagar Dam (Krishna river, Telangana/Andhra Pradesh).
- Hirakud Dam (Mahanadi river, Odisha) — one of the longest dams in the world.
Jawaharlal Nehru called large dams "temples of modern India," viewing them as symbols of technological progress and national development.
Problems with Large Dams
- Despite their benefits, large dams have faced significant criticism:
- Displacement of people: Millions of people, mostly tribal and rural communities, have been displaced by dam reservoirs without adequate rehabilitation.
- Destruction of forests: Forests are submerged in reservoirs, destroying biodiversity.
- Silting: Dams fill with silt over time, reducing their storage capacity.
- Earthquakes: Reservoirs can induce seismic activity.
- Deposition of sediment: Rivers downstream are deprived of fertile silt, affecting agriculture.
The Narmada Bachao Andolan (Save the Narmada Movement), led by Medha Patkar, protested against the Sardar Sarovar Dam on the Narmada River, raising questions about the social and environmental costs of large dams.
Traditional Water Harvesting Systems
- India has a long tradition of ingenious local water conservation systems:
- Khadins and Johads (Rajasthan) — earthen check dams to collect rainwater.
- Baolis/Stepwells (Rajasthan, Gujarat, Delhi) — ancient wells with steps leading down to water.
- Bamboo drip irrigation (Meghalaya) — traditional system of channelling water through bamboo pipes.
- Kuls (Himachal Pradesh) — channels that carry water from glaciers to terraced fields.
- Eris (Tamil Nadu) — tanks used for over 2,000 years to store water for irrigation.
- Surangam (Kerala and Karnataka) — horizontal water harvesting tunnels.
- Rooftop rainwater harvesting (Shillong, Rajasthan) — collecting and storing rain directly from rooftops.
Bhakra Nangal Dam
The Bhakra Nangal Dam on the Sutlej River, completed in 1963, is India's largest dam (226 metres tall). It irrigates over 10 million hectares and generates 1325 MW of electricity. It transformed the arid Punjab plains into the breadbasket of India during the Green Revolution.
The Narmada Bachao Andolan
The construction of the Sardar Sarovar Dam on the Narmada River was expected to displace over 320,000 people, mostly from tribal communities. Medha Patkar and activists lived in protest, raising questions about "development for whom." The Supreme Court allowed the dam to proceed but mandated rehabilitation of displaced people.
Bamboo Drip Irrigation in Meghalaya
The Khasi and Jaintia tribes of Meghalaya have used a 200-year-old bamboo drip irrigation system that channels spring water to farms through an intricate network of bamboo pipes. Water can be delivered to each individual plant precisely, making it far more efficient than flood irrigation.
Eris of Tamil Nadu
Tamil Nadu's ancient eri (tank) system, dating back over 2,000 years, consists of interconnected tanks that harvest monsoon runoff. They recharge groundwater, prevent flooding, and supply water for irrigation during dry months. Over 39,000 such tanks still exist in Tamil Nadu.
Johads of Rajasthan
In the water-scarce Alwar district of Rajasthan, villagers revived ancient johad (earthen embankment) systems under the leadership of environmental activist Tarun Bharat Sangh. The revival of johads recharged groundwater and even brought back the Arvari river, which had dried up for decades.
Rooftop Rainwater Harvesting in Shillong
Shillong, Meghalaya receives among the highest rainfall in the world but faces water shortages in dry months. Rooftop rainwater harvesting — collecting rainwater from rooftops in storage tanks — has been adopted by many households to bridge the gap, showing that even water-rich regions need conservation.
Key Terms
- Water scarcity: The lack of sufficient available freshwater to meet the demand.
- Multi-purpose project: A dam project that serves multiple purposes — irrigation, power generation, flood control.
- Rainwater harvesting: Collecting and storing rainwater for later use.
- Aquifer: An underground layer of rock or sediment that holds groundwater.
Common mistakes
- Do not state that India has water scarcity only because it lacks rainfall — the real issues are uneven distribution, seasonality, and over-exploitation.
- The Narmada Bachao Andolan was not against development — it was for just and fair rehabilitation of displaced people.
Summary
India has abundant water resources but faces growing scarcity due to uneven distribution, seasonal variation, and over-exploitation. Multi-purpose dams like Bhakra Nangal have transformed agriculture and power generation, but at social and environmental costs. Traditional water harvesting systems — johads, eris, bamboo drip irrigation — offer sustainable local solutions.