Construction of Dams: advantages and Disadvantages

Description

Context:

It is important to note here though that dams are not victims of disasters; they, in fact, exacerbate disasters.
While the actual cause of the February 7 floods is under investigation, pegging it as a natural disaster may be incorrect.
A June 26, 2019 order of the Uttarakhand High Court questioned the use of explosives on the Rishiganga site — that too for illegal mining in the name of dam construction.

Concern:

The use of explosives has repeatedly been questioned for dam construction, and the construction of other infrastructure projects, such as roads, in the fragile Himalayan State.
Other than this, deforestation takes place when dams are constructed. While compensatory afforestation is the norm, it is often flouted.
The construction material that is supposed to be dumped on separate land is often dumped into the rivers. It would be naïve to assume that a disaster in Uttarakhand that involves dams was ‘natural’.

Chopra committee report:

The Chopra Committee report of 2014 brings more clarity on how dams exacerbate a disaster such as floods.
The committee was formed to assess whether dams exacerbated the 2013 floods in the State where over 4,000 people were killed, mainly in the Kedarnath Valley.
Its report mentions how dams exacerbated the 2013 deluge, mainly as riverbeds were already raised from the disposed muck at the dam construction sites, and could not contain the sudden increased flow from floodwaters.
The report presents evidence to prove that dams are not only damaged in floods, they also cause immense damage in downstream areas.
The Chopra Committee suggested that 23 of the 24 proposed dam projects it reviewed be cancelled for the potential damage they could do.

Impact of climate change:

To make matters worse, Himalayan glaciers are receding and disintegrating as a result of climate change, and the snow cover in the Himalayas is also thinning.
Research also shows how an increased number and volume of glacial lakes should be expected as a direct impact of increased temperatures.
For dams, this means rapid increase or decrease in the reservoir water level. It also means that the projections on the life of a dam reservoir may not stand due to erratic events, such as floods, that could rapidly fill a reservoir with muck and boulders brought along with the floods.
There is also the threat of earthquakes. In terms of earthquake risk, Uttarakhand lies in Seismic Zone-IV (severe intensity) and Seismic Zone-V (very severe intensity).

Conclusion:

Irrespective of the evidence, the Uttarakhand government plans on continuing to build dams as a source of revenue.
The State plans to construct up to 450 hydropower projects of 27,039 MW installed capacity.
Clearly, the Uttarakhand government has chosen to ignore the disastrous impacts of rampant dam-building. It is clear that dams worsen disasters, and for this to be ignored by the State authorities is unfortunate.