Water Scarcity, Usage, Quality, and Regulation
1. Key Definitions (Do Not Use Interchangeably)
- Water Shortage: When a person does not have enough water to meet daily needs (even if saline water is available).
- Water Scarcity: When available freshwater sources are inadequate to meet the demand of the population.
-
Water Stress: When current demand is being met, but sources are depleting.
- Technical threshold: <1700 m³/person/year
- India’s status: ~1400 m³/person/year → already water-stressed.
2. Global Freshwater Availability
- 71% of Earth’s surface is water, but:
- 97.5% is saline (oceans)
- 2.5% is freshwater
- Most is locked in glaciers and ice caps
- <1% is accessible freshwater
3. Water Usage in India (Broad Categories)
| Sector | Approx. Usage | Key Insights |
|---|---|---|
| Agriculture | 91% | Rice, sugarcane, wheat, cotton use 90% of irrigation water |
| Household | 5% | Urban: 135 LPCD; Rural: 55 LPCD (Jal Jeevan Mission) |
| Industry | 2–4% | Power generation and AI have significant water footprints |
💡 Note: Although agriculture uses the most water, efficiency improvements and crop diversification (e.g., millets) can reduce stress without reducing output.
4. Water Quality
A. Types of Contaminants
| Type | Examples | Impact & Treatment |
|---|---|---|
| Pathogenic | Bacteria (Cholera, Typhoid) | Fast-acting, easier to treat |
| Geogenic | Arsenic, Fluoride, Nitrates | Slow, long-term exposure; hard to treat |
B. Sources of Contamination
- Geogenic: Natural (rock formations)
-
Human-induced:
- Poor sanitation (e.g., untreated sewage)
- Industrial discharge
- Agricultural runoff (fertilizers → algal blooms)
C. Testing & Standards
- Sensory checks (smell, taste, color) are inadequate.
- Official standard: IS 10500
- Labs: NABL-accredited labs for testing
- Regulators: Central & State Pollution Control Boards
5. Regulatory Bodies & Initiatives
- Central Pollution Control Board (CPCB)
- State Pollution Control Boards (SPCBs)
- Jal Jeevan Mission: Aims 55 LPCD in rural areas
- Swachh Bharat Mission: Reduced waterborne diseases
ℹ️ Note: Pollution control boards primarily regulate industries—not village ponds or agricultural runoff.
6. Entrepreneurial Opportunities
- Water testing and treatment technologies are growing fields.
- Different contaminants require different tech:
- RO/UV for biological contaminants
- Specialized filters for arsenic/fluoride
Exam Tip
Focus on differentiating between water shortage, scarcity, and stress. Remember the numerical thresholds and sector-wise usage percentages. Link water quality issues to health impacts and regulatory bodies. Use examples like Jal Jeevan Mission and geogenic contaminants for context. Keep answers structured with clear definitions and examples.