📚 Class 10 Geography – Chapter 3
💧 Water Resources
🌍 Water
- Three-fourths (3/4th) of Earth’s surface is covered with water.
- Only a small proportion is freshwater 💦 (usable for humans).
- Water = Renewable Resource (नवीकरणीय संसाधन).
🚱 Water Scarcity & Need for Conservation
⚡ Reasons for Water Scarcity (जल संकट):
- Over-exploitation (अत्यधिक दोहन) of water.
- Excessive use in agriculture & industries.
- Unequal access among different social groups.
- Poor quality of available water in some regions.
⚡ Why Conserve & Manage Water?
- Protect health from water-borne diseases 🦠.
- Ensure food security 🌾.
- Continue livelihoods & productive activities.
- Prevent ecosystem degradation (पारिस्थितिकी तंत्र का क्षरण).
🏞️ Multi-Purpose River Projects & Integrated Water Management
- Ancient India: conserved water by building reservoirs, lakes, canals & embankments.
- Modern India: continues this tradition by constructing dams (बांध) across river basins.
🏗️ Dams
👉 Definition:
A dam is a barrier built across flowing water 🌊 that obstructs, directs, or slows the flow, creating a reservoir/lake.
✅ Uses of Dams:
- Irrigation (कृषि सिंचाई).
- Electricity generation ⚡.
- Water supply (domestic & industrial).
- Flood control 🌊.
- Recreation, navigation 🚢, and fish breeding 🐟.
⚠️ Side Effects of Dams:
- Disturbs natural river flow → harms aquatic life 🐠.
- Submerges vegetation & soil 🌱.
- Displacement of local people 🏚️.
- Triggered environmental movements:
- Narmada Bachao Andolan ✊
- Tehri Dam Andolan ✊
- Instead of controlling, dams sometimes cause floods.
- Soil erosion, earthquakes, pests & pollution increase.
✅ Exam Tip:
Prepare examples of movements (NBA, Tehri) + uses & problems of dams → these are frequent board exam questions.
💧 Rain Water Harvesting (वर्षा जल संचयन)
🌦️ Meaning (अर्थ)
- A simple method in which rainfall is collected for future usage.
- Stored rainwater can be used for:
- Drinking 🚰
- Irrigation 🌾
- Recharge of groundwater 🌍
🏞️ Methods of Rainwater Harvesting in India
⛰️ Hill & Mountainous Regions
- ‘Guls’ / ‘Kuls’ in Western Himalayas → diversion channels for agriculture.
🏠 Rooftop Harvesting (Rajasthan)
- Common for drinking water storage.
- Especially important in water-scarce areas like Rajasthan.
🌊 Flood Plains of Bengal
- Inundation channels (जल-भराव नहरें) → irrigate fields during floods.
🌵 Arid & Semi-Arid Regions (Rajasthan)
- Fields converted into rain-fed storage structures.
- Examples:
- Khadins (Jaisalmer) 🌾
- Johads (other parts of Rajasthan) 💧
🏚️ Tankas (Rajasthan – Bikaner, Phalodi, Barmer)
- Underground tanks inside houses/courtyards.
- Store rainwater & also keep underground rooms cool during summer ❄️.
🏛️ Tamil Nadu – First State
- Made rooftop rainwater harvesting compulsory for all houses 🏠.
- Legal punishment for defaulters ⚖️.
⭐ Importance of Rainwater Harvesting
- Reduces water scarcity 🚱.
- Recharges groundwater 🌍.
- Ensures drinking water supply 💧.
- Environment-friendly & sustainable 🌱.
✅ Exam Tip:
Always remember Tamil Nadu → 1st state to make rooftop RWH compulsory.
Also examples of Kuls, Khadins, Johads, Tankas are frequent short-answer questions.
