2018 Kerala Floods

Causes and Triggers of the 2018 Kerala Floods

Introduction :

The 2018 Kerala floods were a devastating natural disaster that affected the southwestern state of India. The floods, which occurred between May and August 2018, resulted in massive destruction of infrastructure, loss of lives, and displacement of millions of people. Understanding the causes and triggers of these floods is essential for effective disaster management and mitigation strategies. This article explores the various factors that contributed to the 2018 Kerala floods, including meteorological, geographical, and human-induced factors.

1. Heavy Monsoon Rainfall :

One of the primary causes of the 2018 Kerala floods was the unprecedented heavy monsoon rainfall. Kerala typically receives a significant amount of rainfall during the monsoon season, but in 2018, the state experienced exceptionally heavy rainfall for an extended period. The rainfall was attributed to multiple low-pressure systems, a strengthening of the southwest monsoon, and the formation of a cyclonic circulation over the Arabian Sea. The excessive rainfall resulted in swelling rivers, overflowing reservoirs, and widespread flooding across the state.

2. Topographical Factors :

Kerala's unique topography also played a role in the severity of the floods. The state is characterized by the Western Ghats mountain range running parallel to its coastline, creating steep slopes and narrow river valleys. This topography, combined with the heavy rainfall, led to rapid runoff and increased water flow downstream. The steep slopes exacerbated the speed and force of the floodwaters, causing landslides and further destruction.

3. Dam Mismanagement and Water Release :

Mismanagement of dam reservoirs and the subsequent release of excess water during the floods worsened the situation. Several dams, including the Idukki Dam and the Mullaperiyar Dam, reached their maximum capacity due to the heavy rainfall. In order to prevent dam failure, water was released into downstream areas, resulting in sudden and uncontrolled flooding. The management of dam water release became a critical challenge, highlighting the importance of effective dam management protocols during extreme weather events.

4. Deforestation and Environmental Degradation :

Human-induced factors such as deforestation and environmental degradation contributed to the severity of the floods. The loss of vegetation cover, especially in the Western Ghats, disrupted the natural water absorption and retention capacity of the land. Deforestation for agricultural expansion, urbanization, and illegal construction further exacerbated the impacts of the heavy rainfall. The absence of natural buffers and increased surface runoff from degraded lands led to faster water flow, soil erosion, and heightened flood risks.

5. Urbanization and Encroachment of Floodplains :

The rapid and unplanned urbanization in Kerala, particularly in low-lying areas and floodplains, exacerbated the flood situation. Encroachment of floodplains and construction on water bodies reduced the natural capacity of these areas to absorb excess water. The conversion of wetlands and paddy fields into concrete structures increased the vulnerability of urban areas to flooding. As a result, floodwaters had limited space for dispersion, leading to waterlogging and prolonged inundation in urban centers.

6. Climate Change and Changing Weather Patterns :

While the direct attribution of the 2018 Kerala floods to climate change is complex, changing weather patterns and climate variability likely played a role. Climate change models suggest an increase in the intensity and frequency of extreme rainfall events. Kerala's vulnerability to such events may be influenced by climate change, although further research is needed to establish the exact link between the floods and long-term climatic changes.

Conclusion :

The 2018 Kerala floods were triggered by a combination of factors, including heavy monsoon rainfall, unique topography, dam mismanagement, environmental degradation, urbanization, and potentially, climate change. Recognizing these causes is crucial for implementing effective flood management strategies, including improved dam management, sustainable land use practices, and climate resilience measures, to mitigate the impact of future flood events.