Roadmap for Answer Writing
1. Introduction
- Brief overview: Start with a short introduction on the frequency and impact of floods in India.
- Key Fact: According to the National Disaster Management Authority (NDMA), over 40 million hectares of India’s total 329 million hectares are flood-prone. Every year, floods affect 75 lakh hectares of land, leading to the loss of 1600 lives and causing damages worth Rs. 1805 crores.
2. Factors Contributing to India’s Vulnerability to Flooding
- Monsoon Rainfall: Emphasize the importance of the monsoon season, during which India receives 70%-90% of its annual rainfall. This leads to flash floods and river overflow in many regions.
- Fact: India’s reliance on the monsoon season for water leads to flooding when rainfall exceeds the drainage capacity.
- Himalayan River Systems: Highlight the role of rivers like the Ganges and Brahmaputra, which frequently flood due to their sediment load, glacial melt, and heavy monsoon rains.
- Fact: These rivers, carrying large amounts of water, flood vast plains in northern and northeastern India, particularly during the monsoon.
- Long Coastline: Discuss the vulnerability of India’s 7500 km coastline to tropical cyclones, which bring storm surges and heavy rainfall.
- Fact: The 2023 Chennai floods, caused by Cyclone Michaung, exemplify how coastal areas are affected by cyclones, which trigger floods.
- Climate Change: Address how climate change is increasing the frequency and intensity of rainfall, exacerbating flood risks.
- Fact: In the Himalayas, increased precipitation in shorter periods is a direct consequence of climate change, leading to more severe floods.
3. Causes of Flood Disasters in Different Regions
- Unregulated Development: Discuss how poor adherence to building codes and environmental regulations increases flood risk, particularly in hilly terrains.
- Example: The 2022 Dehradun floods, where construction on the Song riverbed exacerbated the flooding.
- Unplanned Urbanization: Explain how construction on floodplains reduces the natural absorption capacity of the land, leading to urban flooding.
- Example: The 2023 floods in Delhi, caused by encroachment on the Yamuna floodplains.
- Deforestation: Describe how deforestation contributes to soil erosion and increased runoff, which amplifies flood risks.
- Example: In 2019, deforestation in the Western Ghats contributed to severe flooding in Karnataka and Kerala.
- Dam Construction: Highlight how the construction of dams and hydropower projects in the Himalayas has intensified floods by disrupting river systems.
- Example: The 2013 Uttarakhand floods and the 2023 floods in Sikkim were worsened by dam operations and poor management.
4. Conclusion
- Summarize the key points: Briefly conclude by emphasizing the need for better planning, policy enforcement, and climate adaptation strategies to reduce flood risks.
- Solution: Suggest a comprehensive approach involving urban planning, reforestation, better floodplain management, and effective river systems.
Relevant Facts to Include in the Answer
- Flood-Prone Area: More than 40 million hectares of India’s total 329 million hectares are flood-prone.
- Annual Flood Impact: On average, floods affect 75 lakh hectares of land, causing a loss of 1600 lives annually.
- Monsoon Impact: India receives 70%-90% of its annual rainfall during the monsoon, which contributes to flash floods.
- Himalayan River Systems: Flooding in the Ganges, Brahmaputra, and their tributaries is frequent due to a combination of glacial melt, sediment load, and monsoon rainfall.
- Coastal Vulnerability: The 7500 km coastline is vulnerable to tropical cyclones, such as Cyclone Michaung causing Chennai floods in December 2023.
- Climate Change: Climate change is causing increased rainfall intensity, especially in the Himalayas, leading to flash floods.
- Unregulated Development Example: Unregulated construction on the Song riverbed led to the 2022 Dehradun floods.
- Urbanization Example: The 2023 Delhi floods were exacerbated by encroachments on the Yamuna floodplains.
- Deforestation Example: Deforestation in the Western Ghats caused floods in Karnataka and Kerala in 2019.
- Dam Construction Example: The 2013 Uttarakhand floods and 2023 Sikkim floods were worsened by dams and hydropower projects.
Model Answer
Introduction
India is highly vulnerable to flood-related hazards due to several natural and human-induced factors. Over 40 million hectares (mha) of India’s total 329 mha geographical area are flood-prone. On average, floods affect 75 lakh hectares annually, resulting in the loss of 1600 lives and damages worth Rs. 1805 crores. Below are the key factors contributing to India’s flood vulnerability:
1. Monsoon Rainfall
India receives 70%-90% of its annual rainfall during the monsoon season, leading to excessive rainfall and flooding in many regions. This intense rainfall often overwhelms existing drainage systems and causes river systems to overflow.
2. Himalayan River Systems
The Ganges, Brahmaputra, and their tributaries frequently experience extensive flooding due to factors like heavy sediment load, glacial melt, and monsoon rainfall. These rivers carry a massive volume of water during the rainy season, leading to floods in the lowland areas.
3. Long Coastline
With a 7500 km coastline, India is highly susceptible to tropical cyclones originating from the North Indian Ocean. The Chennai floods in December 2023, triggered by Cyclone Michaung, highlight the vulnerability of coastal cities to storm surges and heavy rains.
4. Climate Change
Climate change has caused increased frequency and intensity of rainfall, exacerbating the risk of floods. In regions like the Himalayas, there is a noticeable increase in the intensity of rainfall within shorter periods, which leads to flash floods.
Causes of Flood-Related Disasters in India
1. Unregulated Development
Poor adherence to building and environmental regulations, particularly in hilly terrains, has contributed to flood disasters. For instance, unregulated construction on the Song riverbed led to the Dehradun floods in 2022.
2. Unplanned Urbanization
Unplanned construction on floodplains and wetlands has reduced the natural absorption capacity of the land, aggravating flood risks. The 2023 Delhi floods were a direct consequence of encroachment on the Yamuna floodplains.
3. Deforestation
Deforestation for mining, roads, and tourism increases soil erosion and runoff, contributing to flooding. The floods in Karnataka and Kerala in 2019 were partly caused by deforestation in the Western Ghats.
4. Dam Construction
The construction of hydropower projects in the Himalayan region has intensified floods. The Uttarakhand floods in 2013 and the Sikkim floods in 2023 were aggravated by dam-related issues, including the release of excess water and poor planning.
Conclusion
Addressing India’s vulnerability to floods requires a multifaceted approach, including better urban planning, reforestation, improved drainage infrastructure, and effective river management. Steps to mitigate climate change effects are also crucial in reducing future flood risks.