Dams and Damages

Context: While the recent Uttarakhand flash floods pictures dams as the victims of natural disaster, however, in contrast, they are likely to exacerbate natural disasters.

Dams as the promoter of natural disaster:

• Use of Explosives and Illegal Mining: in the name of dam construction and other infrastructure projects like roads in fragile Himalayan states. (questioned by Uttarakhand High Court)
• Deforestation: while norms like compensatory afforestation are often flouted.
• Unsustainable construction: construction material that is supposed to be dumped on separate land is often dumped into the rivers.
• Findings of the Chopra Committee Report (2014): an expert body to assess whether dams exacerbated the 2013 floods.
  • As riverbeds were already raised from the disposed of muck at the dam construction sites, and could not contain the sudden increased flow from floodwaters. 
  • Dams are not only damaged in floods; they also cause damage in downstream areas, as they increase the destructive capacity of the water that flows downstream of the barrage. 
• Increase threat of Earth Quakes: When dams are constructed in Seismic Zone-IV (severe intensity) and Seismic Zone-V (very severe intensity). 

Role of Climate Change: in the recent disaster.

• Receding of glaciers: Himalayan glaciers are receding and disintegrating due to climate change, and the snow cover in the Himalayas is also thinning.
• Increased glacial lakes: an increased number and volume of glacial lakes should be expected as a direct impact of increased temperatures.
• Lower life of dams: Erratic events, such as floods, that could rapidly fill a reservoir with muck and boulders brought along with the floods.