Ganga saga part II: redesign dams, not rivers

By Sunita Narain
Last Updated: Monday 17 August 2015

gangaEngineers require re-training, not the Ganga. This is where I had left our conversation last fortnight. Why did I say this? The inter-ministerial committee I participated in as a member was discussing how much the ecological flow—the water that should be left in the river for ecosystem and livelihood purposes—should be at all times. How much water is needed for the river to be a river; and not a drain?

The committee’s deliberations had reached a flashpoint. My colleagues at Centre for Science and Environment had analysed hydrological data to recommend an ecological flow regime that allowed 50 per cent of the total flow of the river for six months of lean season. In addition, we proposed that during the high discharge season hydropower development could take as much as 70 per cent of the total water. We showed that this 30:50 ecological flow regime would allow hydropower to make most of the river flow and, therefore, would not have much impact on the total energy generated and tariff. Run-of-the-river projects, which used flowing water as the raw material for energy, generated as much as 80 per cent of their energy in six months.

But this proposal was unthinkable for hydropower engineers. They had “designed” their projects on either zero e-flow or at the most 10 per cent. In this way, they would generate power with every drop of water in the low-discharge season. IIT-Roorkee, which is a key consultant to the government and to private hydropower developers, was asked to review the analysis. It provided a confidential note to the chairperson, disputing our analysis with calculations to show that tariff would increase by 30-60 per cent in the 30:50 scenario.

This view of engineers was adopted as gospel. The draft final report circulated to all members provided for 20-25 per cent flow for nine months and only up to 30 per cent for the rest of the three months. We asked for raw data on which IIT-Roorkee had based its analysis. We asked for this because our calculations were based on hydrological data provided by the same institution. The data was unavailable. But when we went through the IIT-Roorkee papers with a fine-tooth comb we found hydrological data of two projects—330 MW Srinagar project on the Alaknanda and 520 MW Tapovan Vishnugad on the Dhauliganga, both tributaries of the Ganga—which had been used for analysis.

We compared this data with what had been provided earlier to find one modification: the quantum of flow in the river had drastically and inexplicably reduced. Since there was no water in the river, in all seasons, energy generation reduced and, therefore, any provision for higher e-flow would inevitably lead to huge increases in tariff. Delicious maths! We then took up the matter with the chairperson. Our question was: what was the source of this raw data and how had it mysteriously changed? This questioning brought some changes. The subsequent report included a provision for 50 per cent e-flow, but only in situations where there is “drastic” reduction in water.

Therefore, the final report of the committee has accepted the need for 50 per cent flow but with conditions, which leave it vague and weak in application. We have differed and given an alternative view. Our analysis shows that winter (lean) flow is less than 10 per cent of the high monsoon flow in almost all 24 projects for which hydrological data is available. In other words, if less than 50 per cent water is left in the river, it will be reduced to a trickle in these months.

The report is now with the government for it to take a final view. Our position is clear: it is possible for hydropower development to be feasible, even if there is a mandatory provision for 50 per cent e-flow for six months of lean season. It is not too much to give for a flowing, living river.

But I believe this issue raises bigger concerns that need to be discussed. Firstly, the question of how the potential of hydropower generation is arrived at. In this case, the Central Electricity Authority estimated hydropower potential way back in the late 1980s. This estimation did not take into account e-flow, competing needs of society for water or indeed anything else. But any reduction in this “potential” is seen as a financial and energy loss. Any reduction is resisted. But what is not questioned is the very basis of the potential itself.

Secondly, there is the question of cost of generation. Energy planners push for hydropower because they say the tariffs are low and this source provides power during peak demand hours. But they discount water used as raw material and the necessity of a flowing river.

Thirdly, there is the question of making hydel energy sustainable. Currently, the way projects are being executed is disastrous. But if any project is stopped, states ask for compensation—as Uttarakhand is doing—for not destroying the environment. This sets a bad precedent as it induces states to degrade the environment recklessly or be paid to be good. But this also happens because there is no framework to establish the boundaries for resource use. It is necessary to establish sound principles for hydropower development—ecological flow and ideal distance between projects.

The fact is that rivers cannot and should not be re-engineered. But dams can certainly be re-engineered to adapt to these limits.

Environmental flows for Kumbh 2013 at triveni sangam, Allahabad

The impacts of water infrastructure and climate change on the hydrology of the Upper Ganges river basin

Hydrology of the upper ganga river


Assessment of environmental flows for the Upper Ganga Basin: summary report



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  • It is necessary to see

    It is necessary to see rivers should flow even in dry season, particularly in summer. It is very imp in view of enviromental and ecological protection. Projects should design qccordingly.

    Posted by: Anonymous | 7 years ago | Reply
  • Madam, Delicious Math, if

    Delicious Math, if there is private participation in Hydel Power, possibly to divert a lot black money into such projects, calculating the ROI for such investments, as a supposedly economist PM, which I seriously doubt, his policies are Inflationary and he believes, market forces will take care of ALL issues ! If the CSE members stick to their points of view we will perhaps have access to affordable Hydel Power, thank you

    Posted by: Anonymous | 7 years ago | Reply
  • Human design, in general, is

    Human design, in general, is detrimental to rivers. Engineers' solutions are particularly dangerous because of the simple reductionist approach they tend to take to deal with some of the most complex and dynamic systems on the planet.

    Posted by: Anonymous | 7 years ago | Reply
  • Kudos to Avikal Somvanshi for

    Kudos to Avikal Somvanshi for the pictorial presentation of real state of Ganga-after washing our sins! I am a geologist by profession and training, but seeing the plight of the River I think I am becoming a spiritualist. I am afraid that the Ganga which descended from the heavens to cleanse our souls, may change her mind in times to come and go back to her parental home-unless, we mend our ways. As long as we didn't know engineering, hydrology and geology, we used to regard the Ganga as a deity, as a River. Alas, now for us and all the learned people, it is nothing but a large drain, which is meant to carry our shit.
    No government on the earth has the money to clean the mess we have created. It is high time we learn to clean the entire stretch. Ganga needs a high flow to carry away the load. Less water and change in rainfall pattern and concrete forests on the river banks has adversely affected the river. If the trend continues, Ganga will find its own 'mukti' and vanish for ever. That would be the end of all the ills I suppose!

    Posted by: Anonymous | 7 years ago | Reply
  • Ms, Sunita Narain, many

    Ms, Sunita Narain, many thanks for raising issue of utlisable discharge vis-a-vis existing estimated hydro power potential.
    With paradigm shifts, its time re-estimation is attempted no sooner than later, lot of water has already flown down these rivers post 1972 United Nations Conference on the Human Environment and ÔÇ£weÔÇØ have become a bit wiser as well in asking our selves as to how do we handle our Natural Resources for sustainable development. We need power (inclusive of hydro power) and we need rivers as well, I am sure none would disagree on it?
    The concept of e-flow is to be integrated in our hydro power layouts/designs, which I am sorry to say does not exist at present inspite of (if I remember correctly) CBIP guidelines/publication already advocating a 30 % of d/s e-flow in streams (without calling it as such).

    Posted by: Anonymous | 7 years ago | Reply
  • River Tampering is crime in

    River Tampering is crime in law and sin in spirit. It is easy for engineers to sit in their mighty towers and speculate with figures provided by some pseudoscientific body and deliberate on it to arrive at some confidential range of solutions on paper. Here they are acting only as computers and with the dictum of ÔÇÿtrash in trash outÔÇÖ the results are erroneously inconsistent with reality. It is here that opportunism holds sway. Ambitions of some are converted into opportunity to distort and opportunity to award. In calculating flows hydro geological data is necessary but what if it is skewed in first place.Hydrogeological calculations is not rocket science. It is the simplest branch of civil and earth engineering. The question is Law and propriety. Which law permits this unless it is generating promised electricity on paper and profits for contractors. Ecological costs of any hydel projects are humongous and impacts are impossible to calculate .Surely they can be manipulated. What happened to Madhav Gadgil Report on Sahayadris?With frequent floods some people wanted to contain Brahmaputra by civil constructions on the banks .Later after much efforts and costs it was shelved.A river is a part of ocean system .You canÔÇÖt tame it at any costs .But some people will try it to fill their coffers. God save them, not Ganga!!

    Posted by: Anonymous | 7 years ago | Reply
  • Dear Sunita, I always

    Dear Sunita, I always appreciate your comments on important issues, but this one confuses me. Your description of the problem is not very clear. As an engineer I thought I knew how hydro-electricity generation worked; namely, the head and volume of water is utilised but then returned to the watercourse - in which case there is no diminution of the flow in the river. Have I missed something? Is the water diverted to another catchment? Or is the problem the related to the plan and timing for releasing dammed water? Please explain. Best regards.

    Posted by: Anonymous | 7 years ago | Reply
  • I think the solution lies in

    I think the solution lies in storage dams where we can maintain flow in rivers in lean seasons and can generate hydro power also.

    Posted by: Anonymous | 7 years ago | Reply
  • Dear Barry, I am sorry that

    Dear Barry, I am sorry that this was not clear in this article. I had explained it in the first part of the Ganga saga.

    But basically, these are run of the river projects, which would return water back to the river, except that the engineers have designed projects to take all water from the river for diversion for energy generation for and therefore, there are stretches when there is no water in the river. The problem is compounded by the fact that there are many projects which literally start as the last ends and so the dry stretch extends.

    Posted by: Sunita Narain | 3 years ago | Reply