Chapter-3
Water Resources
Notes
Reasons for water scarcity
- Due to the variations in special seasonal and animal precipitation.
- Over Exploitation, excessive use and unequal access to water.
- Water Scarcity is the outcome of large and growing population.
- A large population means more water for domestic and of produce more food.
- Water resources are exploited to expand agricultural production, which leads to decline in ground water level.
- It affects water availability and food security of the people.
- Intensive urbanization and industrialization.
- 22% hydro-electricity in India is generated from water.
- Most of the water is polluted by domestic and industrial wastes, chemicals, pesticides, fertilizers etc.
Managing and conserving water resources is the need of the hour- Explain
- To safeguard ourselves from health hazards.
- To ensure food security.
- For continuation of our livelihood and productive activities.
- To prevent the degradation of eco-system.
Hydraulic structure in Ancient India-
- In the first century B.C. at sringaverapur water harvesting system was existed using the flood water from Ganga river.
- During the time of Chandragupta Maurya, dams lakes etc.were built.
- Irrigation system was found in Kalinga, NagarjunaKonda, Bennur and Kohlapur.
- In the 11th Century, Bhopal lake was built.
- In the 14th Century, Lltush constructed a tank in HousKhas(Delhi).
Why are dams called Multi-purpose projects-
Dams are built for irrigation, electricity generation, water supply for domestic and industrial uses, flood control, recreation, navigation, fishing etc.
- Nehru “Dams are temples of modern India.”
In recent years, multi-purpose projects are opposed by many-state-
- Regulating and damming of rivers affect their natural flow, resulting in excessive sedimentation at the bottom of the reservoir.
- Dams make it difficult for the aquatic fauna to migrate.
- Existing vegetation and soils are submerged under water.
- Building of dams creates large scale displacement of local communities. They have to give up their hand, livelihood etc.
- Irrigation changed the cropping pattern. The farmers shift to intensive and commercial crops.
- The social gap between rich and poor are widened.
- Floods occur due to the sedimentation in the reservoir and life and property are devastated.
- Earthquakes, water-borne diseases, pollution from the excessive use of water.
Rain Water Harvesting
Traditional methods in India used for water harvesting-
- In the hilly areas, the people make diversion challenges like ‘guls’ or ‘kuls’.
- Rooftop rainwater harvesting is being practiced to store drinking water in Rajasthan.
- Innundation channels are developed in West-Bengal.
- In the arid and semi-arid regions, agricultural fields are converted into rainfed storage structure. Eg- Khadins in Jaisalmer, Johads in Rajasthan.
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