By Ramaswamy R. Iyer*
The current Kosi flood is undoubtedly a major national disaster. An embankment has given way in Nepal. The river has changed its course. There are different views on what brought this about, where the responsibility lies, and whether the situation can be reversed. The human tragedy is enormous, and there is widespread criticism of the tardiness and inadequacy of the administrative response to it.
There is also an inter-governmental angle to this disaster. To put it very briefly, the India-Nepal relationship has been badly mismanaged on both sides. Perhaps the best course would be to wipe the slate clean and start afresh. However, that is too complex a subject to be gone into here.
The immediate priority now is of course rescue, relief, assurance of essential supplies, shelter, medical help and so on. Belatedly, after much public criticism, the Central and State Governments seem to be swinging into action. Can they not enlist the assistance or advice of the governmental and non-government agencies that worked to good purpose in Tamil Nadu in the aftermath of the tsunami in 2004?
Causes and Consequences
Causes, consequences, and lessons are matters of great complexity, but may one venture into that dangerous ground with a few tentative remarks? Given the friability and proneness to mass-wasting of the Himalayan system and the waywardness of the Kosi and the heavy load of sediment that it carries, it was probably a mistake to have built a barrage and embankments on that river.
Be that as it may, embankments, even if they do not break down, might cause various problems, such as a rise in the level of the river-bed and the consequent elevation of the river above the level of the ground on either side, possible attacks by the river further downstream, and of course the emergence of water logging and even flooding in the areas ‘protected’ by the embankments because water cannot drain from those areas into the river.
While in some specific instances embankments might have done some good without doing any harm, they are in the case of a river like the Kosi a remedy worse than the disease.
A Minimalist Approach to Embankments and Dams
It might be argued that the arguments against embankments do not apply to dams, as they will provide space for the temporary storage and gradual release of floods, thus moderating them. That seems very plausible, but a dam-and-reservoir project is rarely built exclusively for flood-control. It is generally built for multiple purposes (irrigation, power-generation, flood-control, etc), and there is a conflict in-built into such projects.
Flood-control would require the intended space in the reservoir to be kept vacant for accommodating flood-waters, whereas irrigation or power-generation would require the reservoir to be as full as possible; and as the latter are gainful activities in an economic sense, they are apt to prevail over flood-control.
If the space meant for accommodating floods is not available when the flood comes, the gates will have to be opened in the interest of the safety of the dam, and the downstream area might experience a greater flood than it would have done if the dam had never been built. This has actually happened more than once.
Assuming that a flood cushion is built into a dam project and is operated as such, or alternatively that a dam is built exclusively for flood-control and strictly operated for that purpose, the dam might indeed moderate a flood up to a point; but a flood larger than the ‘design flood’ would raise safety concerns and necessitate the opening of the gates; and this can happen at any time. This is an inherent danger in all dams.
One is not saying that dams and embankments should never be built. All that one can say is that in general these are better avoided, and that where they are absolutely necessary, great care should go into their design, construction, maintenance and operation. In particular, the drainage aspect should receive the utmost attention. The decision-making in such cases should be open, accountable, and fully participative.
Fatalism and Floods
In recommending minimal recourse to dams and embankments, one is not arguing that calamities must be accepted and suffered fatalistically. Consider what we do in the case of earthquakes or hurricanes or tornadoes or tsunamis. Does anyone say that they should be stopped or prevented from happening or controlled?
What everyone would say is that they should be predicted, anticipated, and prepared for; that there should be timely information, a state of preparedness for disaster, the minimization of damage and prompt and adequate response by way of rescue and relief when the disaster actually strikes. Exactly the same point applies to floods.
Floods are natural phenomena. They will occur from time to time, in varying magnitudes and intensities. When the flood waters come, the river needs space to spread and accommodate them until they recede. The natural flood-plain of a river is an integral part of the river. If we build on it, or if we try to contain the river within embankments, we are asking for trouble.
Keys: Adaptation, Information, & Preparedness
Adaptation to floods, timely information, anticipatory preparations for minimizing damage, and prompt action when the flood comes, are the answer. In addition, we can also learn from well-established traditional coping practices evolved over centuries by communities accustomed to periodical floods.
That wisdom is for the future. What do we do about structures already built? If we repair the damage to the embankment and try to put the river back into its old course, we are running the risk of a recurrence of a major disaster in the future.
On the other hand, If we do not rebuild the structures but let the river find its natural course, we might be putting at risk a large number of people who are living and pursuing their livelihoods in areas earlier ‘protected’ by the embankments. That is a difficult choice but not really a dilemma.
Conclusion: Put the Clock Back
The argument that we cannot put the clock back is not valid. Having realized the errors of the past, there is no escape from reversing them over a period of time very carefully, minimizing the pain of readjustment to the extent possible. That applies to global warming and climate change, and it applies equally to the fallacy of ‘flood control’.
*The author is former Secretary, Union Ministry for Water Resources, Govt of India
**Article made available by Mr. Man Mohan on Kosi Discussion Forum