Mains Focus
Mains Focus – 21st April 2025
Question
Dam failures are always catastrophic, especially on the downstream side, resulting in a colossal loss of life and property. Analyze the various causes of dam failures. Give two examples of large dam failures. [10 Marks, GS Paper 2, 2023]
Answer
Dams are vital for irrigation, hydroelectricity, flood control, and water supply. However, when dams fail, the consequences are often catastrophic, especially for downstream regions. Sudden release of vast water volumes leads to widespread destruction, endangering lives, infrastructure, and ecosystems.
Causes of Dam Failures
- Structural Deficiencies
- Poor design, substandard construction, and aging infrastructure contribute to weakened dam walls or foundation instability.
- Inadequate spillways may lead to overtopping during peak inflows.
- Hydrological Events
- Unprecedented rainfall, cloudbursts, and glacial lake outbursts due to climate change can exceed a dam’s designed capacity.
- These events stress dams beyond their structural limits.
- Geological and Seismic Factors
- Dams located in tectonically active zones are vulnerable to earthquakes.
- Landslides triggered by seismic activity may block river flow, causing pressure buildup and eventual breach.
- Operational Mismanagement
- Delayed opening of sluice gates, faulty instrumentation, or human negligence can cause uncontrolled water accumulation.
- Inadequate monitoring and poor communication between agencies further aggravate risks.
- Aging Infrastructure
- Many Indian dams are over 50 years old. Without regular inspection, retrofitting, or de-silting, their structural reliability diminishes.
- Sedimentation and Erosion
- Accumulated silt reduces storage capacity and increases pressure during monsoon.
- Erosion of dam foundations, especially earthen dams, can lead to breaches.
- Sabotage or Conflict
- Though rare, sabotage or targeted attacks can cause dam breaches in conflict-prone areas.
- Though rare, sabotage or targeted attacks can cause dam breaches in conflict-prone areas.
Recent Examples of Large Dam Failures
- Chandrapur Erai Dam Breach, Maharashtra (2022):
- Heavy rainfall led to overtopping, weakening the structure. Several villages were submerged, and evacuations were carried out.
- Sikkim’s Teesta III Dam Failure (2023):
- A Glacial Lake Outburst Flood (GLOF) in North Sikkim destroyed the dam infrastructure, leading to massive downstream flooding and loss of life and property.
- A Glacial Lake Outburst Flood (GLOF) in North Sikkim destroyed the dam infrastructure, leading to massive downstream flooding and loss of life and property.
Conclusion
Dam failures highlight critical gaps in structural safety, climate resilience, and disaster preparedness. The Dam Safety Act, 2021, mandates regular inspections and safety protocols, but effective implementation, use of modern monitoring technologies, and community-based warning systems are essential to prevent future tragedies.
.png)
