This article appeared on infochangeindia.org in April 2009.
The new ‘United Nations World Water Development Report 3’ carries alarming warnings about the impact of glacial melts in the Himalayas. But over 450 hydropower projects are being planned in the Himalayas without taking the consequences of climate change into account, says a report from International Rivers
A comprehensive UN assessment of the earth’s water resources, the recently released ‘United Nations World Water Development Report 3’ (www.unesco.org/water/wwap/), carries a stark message on climate change and its impact on managing water resources.
There is evidence that the global climate is changing and that some of the change is human-induced. Even the minimum predicted global warming for the 21st century — more than twice the 0.6°C increase that has occurred since 1900 — is expected to be significant and disruptive.
The international response has focused primarily on mitigation of climate change through measures such as reducing greenhouse gas emissions, transferring clean technologies, and protecting forests. These measures may slow climate change but they will not halt or reverse it. It will be two generations before the measures even begin to have an effect. And, if successful, they imply a considerably changed future climate. While mitigation of anthropogenic climate change is vital, the blunt reality is that all countries — particularly developing countries that will be hit hardest and earliest — must take measures to adapt to climate change.
Climate change and water
The main impact of climate change on humans and the environment will occur through water. Water availability has a naturally occurring variability, and managing water has always been about managing this variability. Climate change threatens to make this variability greater, shifting and intensifying the extremes, introducing more uncertainty in the quantity and quality of water supply over the long term. More subtly, climate change could alter the timing, magnitude and duration of precipitation (rain or snow).
The impact of climate change is most clearly apparent in snow and ice glacier water resources and river water supply in mountain regions. There is considerable evidence that glaciers have retreated globally since the middle of the 19th century, with the rate of retreat accelerating from the mid-1970s in response to rapid rise in air temperature and changes in the amount of precipitation and its composition, rain or snow. Tropical glaciers are more sensitive to changes in climate than glaciers at higher latitudes.
For water managers, human-induced climate change poses a new set of challenges because they can no longer plan, design and operate hydrologic systems based on historical statistics. Climate change means learning to manage amidst increased uncertainty. It is a new risk to be taken into account in policy development, planning and operations at the global, basin, national, local and company levels. It calls for increasing use of ‘climate knowledge’ to better understand climate variability at different time scales, and to provide the best possible information on future climate, from seasons to decades, for specific decisions and activities.
Retreat of the Himalayan glaciers
Of specific interest to India are details in the report about the impact of climate change on Himalayan glaciers and rivers. The report warns:
“Recent studies have revealed that large Himalayan glaciers are retreating at a rate of more than 30 metres a year, resulting in a 21% reduction in glacier area since the 1980s. The Himalayan region is highly vulnerable to climate change because its major river drainage systems depend on substantial contributions from snow and glacier melt. In India, the river systems originating from the Himalayas (the Ganga, Brahmaputra and Indus) contribute more than 60% to the total annual runoff for all the rivers of India. These river systems hold immense potential as a future water source and drain the major plains of the country. Some Himalayan rivers receive more than half their flow from snow and glacier melt runoff near the foothills of the Himalayas.
“Melting of glaciers and a reduction in solid precipitation in mountain regions will directly affect water resources for domestic supply, irrigated agriculture, hydropower generation and other water-dependent activities. Additionally, it has been observed that there is increased annual runoff and earlier spring peak discharge in many glacier- and snow-fed rivers, indicating a regime shift for these rivers. This trend is projected to continue in response to rising temperatures, resulting in increased summer stream flow in downstream regions receiving melt water from major mountain ranges, followed eventually by reduced stream flow.”
The UN report’s message is clear: that climate change is for real, and adapting to it is a necessity. But how are India’s ‘water managers’ adapting to climate change?
Massive dam-building plans
According to a new study published by the NGO International Rivers, the Government of India is planning massive interventions on rivers in the Himalayan belt without considering the impact of future climate change. The study, titled ‘Mountains of Concrete: Dam Building in the Himalayas’ (www.internationalrivers.org/en/publications) is authored by Shripad Dharmadhikary, a researcher who has been studying water and energy issues for over 20 years.
The study says that over 450 hydropower projects are planned or under construction in the Himalayan region, spanning the four countries of Pakistan, India, Nepal and Bhutan. Of these, 350 projects are being planned on Indian territory, in the states of Uttarakhand, Himachal Pradesh, Arunachal Pradesh and Sikkim. The major projects in Nepal and Bhutan will also supply the Indian grid.
The policy framework in India has been changed, in recent times, to make it easier for private companies to build and operate hydropower projects profitably by being able to set tariffs. This has led to a large number of private companies, many without any previous experience in the sector, jumping in to sign MOUs with state governments for hydropower projects. If all these planned projects materialise, the Himalayan region will have the highest concentration of dams in the world.
The study details the negative impacts of these projects on environment and people, based on experiences from earlier schemes. Besides submergence of large tracts of land, with the consequent displacement of people, damming and diversion of rivers will have impacts downstream due to disruption of flow, affecting people who depend on the river all along its route.
There are also heightened risks related to the region. The Himalayas are a biodiversity hotspot that boasts a number of plant and animal species that are unique to the area. Being an extremely fragile ecosystem, large-scale interventions will be extremely damaging. The region is also seismically active, which means dams could be damaged in the event of an earthquake, with catastrophic consequences.
Floods due to glacial lake outbursts — already witnessed regularly in the Sutlej basin — are another risk. Because the mountains are young and prone to a lot of erosion, the rivers cutting through them carry a heavy silt load that results in relatively rapid sedimentation of reservoirs.
The most serious issue, according to Dharmadhikary, is the impact that climate change will have on hydroelectric projects being planned. With glaciers melting because of global warming, dams will be subjected to greater flows; they must cater to this in their design. Depletion of glaciers over the years will lead to less flow, affecting the performance of dams. Climate change could also cause increases in the frequency of heavy precipitation and glacial lake outbursts. The likelihood of flash floods could rise, threatening the integrity of dams and posing a grave risk to populations downstream.
Dharmadhikary questions the planning of hydropower projects in India on two levels. Firstly, risks introduced by climate change are not being taken into consideration in the planning of dams in the Himalayas, either at the individual project level or in terms of their cumulative impact on a river basin or region. Secondly, if the impacts of climate change are factored in, the projects could turn out to be extremely expensive and poor investments that India can ill afford.
In the context of Dharmadhikary’s assertions, it is useful to look at how hydropower capacity addition is being planned in India.
The responsibility for overall planning and individual approval of large projects rests with the Central Electricity Authority (CEA). A worrying fact, admitted in its 2017 hydropower plan document, is the admission that while a large number of hydro projects are being planned for the northeast, even historical hydrological data on which the design of hydro projects is currently based may not be available for “adequate period for optimum planning”. A reading of the plan document shows that its overwhelming focus — perhaps in response to pressures from the central government — is on efficiency, speed and timeliness of project implementation. Major roadblocks in accomplishing the mission are seen to be delays in obtaining environment and forest clearances, local popular opposition to projects, and delays in the resettlement of project affected people. All these have to be solved in a time-bound manner by other agencies of the central and state governments, so that the CEA can stick to its deadlines.
Since ‘efficiency’ is the CEA’s concern, not displacement, it decries the attempt by state governments to convert (CEA proposed) stored water dam projects to run-of-the-river projects, though the latter would likely result in less displacement. Since ‘cost’ is its concern, not loss of forests, it wants a change in the way forest resources affected by projects are evaluated, to bring down the cost of compensatory measures and thereby the overall cost of hydro projects. What is apparent is that hydropower is the CEA’s responsibility; environment and people are the responsibility of others. Finally, the CEA shows no public sign of being concerned about climate change in its planning of dams in the Himalayas.
A history of disasters
The record of India’s water infrastructure managers in designing and maintaining dams that can withstand exceptional events is not very encouraging. In 1979, extremely heavy rainfall and a swollen river resulted in the collapse of the Matchu dam in Gujarat, leaving 1,500 people dead and 400,000 displaced. In 2007, heavy rains — the highest recorded in 24 years — led to the development of cracks in the Jaswant Sagar dam in Rajasthan, resulting in the Luni river breaching its banks, flooding a number of villages and leaving 50,000 people stranded. The horrendous flooding caused by a breach in the Kosi embankment in 2008, that killed hundreds of people and displaced millions in 10 districts of north Bihar, is still fresh in public memory. Indeed, India’s water management establishment has not yet found a solution to repeated breaches of the Kosi’s embankments over the years, at the root of which lies the river’s heavy silt load.
Hydro project failures have had catastrophic consequences. It is unclear whether anybody has ever been held accountable for any of these failures, or if ‘post-mortems’ are ever carried out to understand the causes of these disasters.
Dharmadhikary’s study calls for comprehensive assessment of the likely impacts of climate change on dams in the Himalayas, before proceeding with the massive building plans. Considering the growing awareness about climate change and the horrific consequences of dam failures, this is a call that must be heeded.
(Kannan Kasturi is an independent researcher and writes on law, policy and governance)
InfoChange News & Features, April 2009