New Delhi Tragedy struck Uttarakhand's Chamoli district on February 7 when a flash flood washed away two bridges and a barrage for a hydropower project, and inflicted heavy damage on another hydropower project while killing nearly three dozen people. The visuals on the social media offer a reminder of the grim Kedarnath floods of 2013, which had led to worse devastation in the ecologically fragile Uttarakhand Himalayas.

Various government agencies and academics have come up with different explanations for what caused the flash flood, and there is no consensus yet.

The model of "development" being practised is making such disasters more likely, says Ravi Chopra, founder director of the People's Science Institute (PSI) at Dehradun, who has been on several committees of different ministries and departments including the erstwhile Planning Commission. Chopra headed an expert panel that produced a report on the 'Assessment of Environmental Degradation and Impact of Hydroelectric Projects during the June 2013 Disaster in Uttarakhand', which documented how the government tweaked rules to accommodate hydropower projects in Uttarakhand.

An IIT Bombay engineer, Chopra completed his PhD from Stevens Institute of Technology, New Jersey, USA. He has authored and/or co-authored 14 books and special reports and published more than 20 research papers in international journals. He was also a member of the government's Working Group on Perspective Planning at the National Commission for Integrated Water Resources Development.

In this interview, Chopra explains why the Chamoli accident will not be the last, and what needs to be done to reduce the negative impacts of climate change on the fragile Himalayas.

Edited excerpts:

What do we know about what happened in Chamoli? The Dehradun-based Indian Institute of Remote Sensing (IIRS) said it was a landslide at an elevation of 5,600 metres in the catchment of the Rishiganga that probably destabilised the freshly accumulated snow and initiated its downward movement. The Wadia Institute of Himalayan Geology (WIHG) announced its initial conclusion that it was "an episodic failure of rock mass & hanging glacier in the Raunthi glacier area".

Two events happened on February 7. There had been snowfall earlier in the week. On February 5 and 6, there was bright sunshine and strong solar insolation. This led to the melting of the snow and some of the ice buried under the snow. The mixture of snow, ice and water—when it moves down a slope—is deadly. It moved down the steep slope of Trishul nala, and in the process, gathered all the sediments, the rocks and boulders that were lying in that valley. This avalanche reached the bottom of the slope into the Rishiganga river and created a flood. Up to this point, this was a natural event. Such events take place often in the Himalayas in remote locations and we do not hear about them.

Now, when such a flood begins to move downstream, it has a lot of energy; it will devastate anything that stands in its way. As the flood moved down the Rishiganga, it encountered a bridge, and it blew the bridge apart. The next barrier was the barrage of the 13.2 megawatt (MW) Rishiganga Hydropower project. It totally destroyed that barrage and moved further down and entered the Dhauliganga valley and the flood now began to move in the Dhauliganga river.

The first obstruction [here] was the barrage of the 520 MW Tapovan Vishnugad project that was demolished in a matter of seconds. The water also entered the intake tunnel of this project and very quickly the rocks and boulders filled the mouth of the tunnel, blocking it and trapping people inside. After removing the barrage of the Tapovan project, the flood moved downstream and finally entered the Alaknanda valley. Alaknanda is a much bigger river; the flood lost a little bit of its power and then it demolished a bridge on the Alaknanda. But as the slope of the Alaknanda became more gradual, the flood lost its energy and by the time it reached Pipalkoti, it had become quiet. So that is the second event.

The first event is a natural event, the second event is a disaster. It is a disaster because human beings have put obstructions in the path of nature, in the path of a river. So, we have to understand this thing. If there had been no barrier, there would have been no damage.

Be it the Chorabari glacier (in case of the Kedarnath tragedy in 2013) or this glacier--part of the Nanda Devi massif in Chamoli--the health of glaciers is an important indicator of the well-being of the Indian Himalayas. What has been the effect of climate change on glaciers?

Over the last 30 or 40 years, glaciologists in India have detected a definite impact of global warming in the form of recession and/or shrinking of glaciers. Smaller glaciers are breaking up--the process is called fragmentation--and very often, the ice and snow melt in the different fragments form lakes. The wall of such a lake is made up of ice and stones, whose melting can create floods of the kind we saw in case of the Chorabari glacier in 2013.

There are rivers like the Yamuna that have only two glaciers and their recession is also a cause for worry because it will lead to decline of water coming into the river. In fact, the bigger glacier of the two is not even in the Yamuna valley, it is in the Tons--or Tamasa--a major tributary of the Yamuna; it comes from the Bandarpunchch glacier and when it meets the Yamuna, it has much more water than the Yamuna. At PSI, we have been looking at the Bhilangana river which originates at Khatling glacier. When we were doing a study of Khatling glacier sometime around 2016, we observed that the glacier had broken up into four fragments and, I think, two or three of them had already formed lakes. So, this is a cause for concern.

The Supreme Court-appointed committee that you headed warned against the building of more dams, especially in the para-glacial region. Yet the government cleared a chunk of them. The government is proceeding with the Char Dham Yatra project despite it being red-flagged by environment activists. What is the effect of all this construction on the mountain ecosystem?

The construction of roads, dams, townships in the mountain areas, definitely has a negative impact on the mountain ecosystem. Most importantly, it leads to the destruction of forests, which are the backbone of the mountain environment. The forests also feed springs. Once the forests go, then there is truly little left to protect the soil cover on the slopes. So, with the rains the soil also comes down and often this can lead to landslides. It also leads to the loss of springs. It is generally difficult to assign the impact of one single project to distant regions like the glaciers. But we know that there is a cumulative impact of all these activities even in the remote areas. So, we may not have quantitative measurements, but we have qualitative evidence.

I recall when we came to Dehradun in 1988, and we used to go to Mussoorie, on any given day, we could see the snow-capped peaks of the high Himalayas. But now when we go to Mussoorie, on most days, the high Himalayas are covered with haze. This haze is nothing but the dust and the pollution that comes from the plains and travels all the way up to the high Himalayas where it meets the tall barrier of snow-capped peaks and the dust and the pollutants settle over there.

Now, this was clear to us that it was the impact of dust and pollutants coming from the plains even when we did not have quantitative evidence. But now, measurements are being made and there are portions, small bits of what is called black carbon or soot, that is found on the mountain top by people who go to study the region. Even if we do not have exact quantitative measurements, sometimes qualitative evidence gives us a note of caution and that is the time when one should apply the precautionary principle. The precautionary principle has been accepted by the courts to mitigate the impact of some of these activities.

Do you see the government taking cognisance of this situation--the cumulative impact of climate change that you talk about and the courts raising their concern, too?

Sometimes there is some effect of the court rulings, sometimes there is an effect of public protest. For example, the different fasts undertaken by G.D. Agrawal led to a concern for the environmental flows in the River Ganga. At least the government now has to make some noise that I am doing something for the river.

Then we also see that sometimes some officials and the government at the Centre is more responsive to the court order. But the state government, I would say, has been more or less unrelenting in pushing for this kind of development. Their argument is that we need the revenue. We do not have any other source of revenue. I think it is high time that the Finance Commissions and the Government of India recognise that the well-being of the Himalayan region is critical for the whole country.

Even if we take just the Ganga basin, we are talking about 400-500 million people, almost half our population. So, they must now begin to recognise that it is important for us to protect our forests and our rivers in the Himalayan states for which the Himalayan states have to be paid an adequate payment for ecological services rendered.

Seven years after the detailed report that you prepared as head of the expert body, do you see any change on the ground?

Yes, there is some change. For example, again, it [the report] added strength to the campaign for ensuring adequate environmental flows in the Ganga basin. Finally, because of G.D. Agrawal's fast and so on, the government had to develop a policy. Second, we see that many projects, especially the small and medium projects, in the private sector have reduced. The private sector realises that the time of construction becomes exceedingly long because of all kinds of court cases and protests; it reduces the profitability of the project as they have to carry the loans for that [duration of] time. They also realise that new alternatives are emerging which are a lot cheaper. A small hydropower project may generate a unit of power for Rs 8-10 per unit. Solar energy will provide me with the same power for Rs 2.5-3 per unit. Therefore, the small and medium companies have reduced their interest in hydropower in Uttarakhand. But projects are also tied up in the courts, so the actual construction of projects after 2014 has been quite low.

Basically, the Centre has responded better than the state government, which is unrelenting.

Uttarakhand has seen an exponential increase in tourists and pilgrims over the last two-three decades, and this creates problems vis-a-vis solid waste management, sewage, construction of hotels. Gangotri National Park breathed easy since 2007-08 when there was a restriction put on the number of people per day. Do you think more and more areas should be put under such entry restriction?

Yes, we have argued that the initial stretch of all Himalayan rivers should be considered as eco-sensitive zones. And, why only the Ganga, Bhagirathi? Alaknanda is an equally important part of the Ganga, so are the feeders that come from various glaciers. Therefore, I think that we must be more serious about protecting the environment with the use of the eco-sensitive zone notification.

Is there a need to widen the eco-sensitive zone or buffer area?

No, the first thing is you apply the principle properly. Right now, nobody cares what that buffer zone is.

The thing is that the government is fixated on enhancing tourism to a few selected locations. So, the Char Dhams become a highly concentrated stretch, the Corbett park becomes another one. But Uttarakhand has not hundreds but thousands of locations that could attract tourists; therefore, there has to be more distributed tourism than this kind of focussed tourism. If there is distributed tourism, and the tourism is home-based in the form of homestays, it will spread the benefits. But, at the same time, we must also ensure the tourists are well educated to not litter the area.

What should be the role of the local community in such cases?

First of all, we should recognise that after the big struggles against the Tehri dam and the Narmada dam in the 1980s, the dam builders have also devised their own strategies to counter protest. And, one of the remarkably successful strategies is to offer certain jobs to local people, even though they are very low-paying jobs. But in an area like Uttarakhand where job opportunities are incredibly low, this manages to split the local communities. And so, time and again, you will find that local communities are divided.

On the other side, I think it is important for social activists to educate the local people on the positive changes that are brought about or that can be brought about by having alternatives. The victories that are won against such kind of damaging projects--we tend to not highlight our own victories.

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