Lecture Notes: Water Resources (Class 10th Geography)

Overview

• Lecture by: PIMS Vikrant Singh Rajput
• Subject: Social Science, Class 10th
• Chapter: Water Resources
• Focus on comprehensive understanding beyond textbook definitions.
• Practical relevance to societal issues, especially regarding multipurpose projects and their impacts.

Key Themes

Definition and Distribution of Water Resources

• Earth's surface is 3/4 covered by water, but only a small percentage is fresh and usable:
  • 97% is saline (oceans).
  • 3% is fresh, out of which:
    • 2% is frozen in glaciers and polar ice caps.
    • 1% is available as surface water (streams, lakes) and groundwater.

Importance of Water

• Essential for all life forms—plants, animals, humans.
• Integral to human activities like agriculture, industry, and domestic uses.
• Water cycle (Hydrological cycle) explains continuous movement through processes of evaporation, condensation, and precipitation.

Issues with Water Resources

Water Scarcity: Causes and Implications

• Caused by:
  • Over-exploitation and unequal distribution.
  • Population growth and increased demand.
  • Pollution leading to unusable water.
  • Industrial and agricultural misuse.
• Impacts:
  • Affects food security and socioeconomic conditions.
  • Environmental degradation and reduced ecosystem functions.

Need for Conservation and Management

• Health hazards: Safe drinking water is essential.
• Food security: Ensuring agriculture is sustainable.
• Environmental stability: Maintaining balance in ecosystems and preventing crises.

Solutions: Water Conservation Methods

Traditional and Modern Methods

Multipurpose River Projects (Dams)

• Provide multiple benefits: irrigation, hydroelectric power, water supply, flood control, and recreation.
• Examples:
  • Bhakra Nangal Dam on Sutlej-Beas river basin for irrigation and power generation.
  • Hirakud Project on Mahanadi river for flood control and irrigation.

Drawbacks of Large Dams

• Environmental and Social Concerns:
  • Displacement of communities and wildlife.
  • Changes in local and downstream ecosystems.
  • Poorly managed dams can increase flood risks.

Alternative: Rainwater Harvesting

• Collecting and storing rainwater locally.
• Advantages:
  • Cost-effective and environmentally friendly.
  • Reduces dependence on large infrastructures.
  • Maintains groundwater recharge.
• Methods:
  • Rooftop rainwater harvesting.
  • Traditional tanks (Tanka) in Rajasthan.

Case Studies

• Shillong, Meghalaya: Despite high rainfall, employs rooftop harvesting to utilize rainwater effectively.
• Tamil Nadu mandate: Makes rooftop rainwater harvesting compulsory for all new buildings.

Conclusion

• Water resources are critical; conservation and management are necessary.
• A balance of large-scale multipurpose projects and localized rainwater harvesting can address water scarcity issues.
• Individual efforts contribute significantly to solving broader water resource challenges.