Question Bank

December 20, 2018 @ 2:00 pm
Question Bank

20th December 2018


 (1 Question)

Answer questions in NOT MORE than 200 words each. Content of the answer is more important than its length.

Links are provided for reference. You can also use the Internet fruitfully to further enhance and strengthen your answers.


Q1. Discuss the impact of hydropower projects on the river Ganga.


  • From aiming for Aviral Dhara (uninterrupted flow) of the Ganga to Nirmal Dhara (unpolluted flow), the government is now simply focussing on a Swachh Ganga (Clean Ganga). While the whole focus of the Clean Ganga project has been on setting up sewage treatments plants and cleaning ghats and banks, but another main issue is that, the river does not have adequate flow of water. With severe pollution destroying the river, and developmental projects critically affecting its flow, the Ganga is in a dire strait.
  • Today, several hydropower projects are mushrooming at the source of the river, which is the Garhwal range of the Himalayas. Unlike other ranges, the Garhwal is narrow. It is from here that many rivers and tributaries of the Ganga basin emerge. These spring- or glacier-fed rivers join one another at different points to form an intricate riverine ecosystem in the Himalayas. The entire basin falls in the seismic zone 4-5, and is highly prone to landslides and land subsidence.
  • The immediate impacts of hydropower projects have been loss of agriculture, drying of water sources, and landslips. As construction in such projects progresses, there is also dumping of muck, which can pose severe threats. Muck dumping during construction of the Alaknanda hydropower project caused devastation downstream in Srinagar in the 2013 flash floods. Such muck is dumped either into the river or in forest areas. After all the massive deforestation, muck dumping, blasting and tunnelling, the hydropower projects thus constructed eventually dry up the river bed as the water is diverted into tunnels. This causes severe distress to aquatic life, and the river bed is no longer even wet in certain stretches. As the Ganga is diverted into long tunnels, de-silted, and directed to powerhouses to churn turbines and generate power, the barren landscape, dried water sources and the obscene muck slopes narrate a story of destruction. This is a far cry from the promise of development.
  • The irony is that even after all this devastation, electricity is not generated as per the intended capacity. For example, the installed capacity of the Maneri dam is 90 MW but it only works at below 40% of its capacity. This is because there is too much silt during the monsoon and reduced flow of water in winters. As glaciers continue to retreat, the silt in the rivers is only going to increase. As the reason for diminished output is natural and not technical, and therefore cannot be remedied, this is only going to cause more problems for future projects. For example, the flow of debris was stopped by barrages in the Alaknanda hydropower project. This escalated the impact of the 2013 disaster, according to the expert committee of the Supreme Court.
  • In the case of the Ganga, these projects also prevent sediments from going downstream. This affects the fertility of the delta downstream and also destroys the unique self-purifying properties of the Ganga.


  • Twenty government committees and reports warn about the anthropogenic activities in these fragile areas and recommend conservation of these areas for food and water security. The government proposed an e-flow notification for the Upper Ganga River Basin. It specified that during the dry season (November-March), 20% of monthly average flow has to be maintained, and during the monsoon season, 30% has to be maintained. The notification stated that existing hydel projects that do not meet e-flow norms must comply within three years. The 20% recommendation is less than the scientific recommendation of 50% (only for existing projects).

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