Environment

Farakka Dam Demolition May Resolve Bihar’s Flood Problem, But Could Cause Damage to Ganga Ecosystem

Environmentalists support Nitish Kumar’s demand to demolish the barrage, but urge caution to ensure the desiltation policy does not damage the river’s ecosystem.

The Bihar floods are possibly the outcome of the Farakka barrage furhter downstream, that blocks the flow of the river, causing silt to deposit upstream. Credit: PTI

The Bihar floods are possibly the outcome of the Farakka barrage furhter downstream, that blocks the flow of the river, causing silt to deposit upstream. Credit: PTI

Water and environment experts have given a thumbs up to Bihar chief minister Nitish Kumar’s demand for the demolition of West Bengal’s Farakka barrage on the river Ganga because it was causing heavy siltation and consequent flooding in Bihar. He urged Prime Minister Narendra Modi to desilt the river and formulate a National Silt Management Policy to ensure that dams and barrages do not lead to heavy deposition of silt upstream while reducing the flow of silt down to the river deltas.

On the other hand, the experts have also cautioned that such a desiltation policy would require careful monitoring and supervision to ensure that the ecosystem of the river is not damaged. The environmentalists are also fearful that unmindful dredging of the Ganga and other rivers may be allowed under this pretence, as the Centre is also planning to create 105 national waterways for which a certain depth will be required in all the rivers for vessels to pass through.

While Kumar had written to Modi regarding the Farakka barrage, he later met the prime minister and raised the issue of having a desiltation mechanism to reduce annual floods.

According to environmentalists and water experts, while Kumar’s idea to remove the Farakka barrage was practical as it would lead to the natural flow of silt with water, they said that there needs to be careful planning before any exercise is undertaken to remove silt along the course of a long river like the Ganga.

As Himanshu Thakkar, coordinator of the South Asia Network on Dams, Rivers and People, pointed out, “Nitish is right when he says that the Farakka Barrage should be removed. It was constructed to divert waters to the Hooghly for ensuring river navigation there. But empirical studies have shown that it hardly served that purpose.”

On the other hand, Thakkar said, like all barrages, Farakka too managed to divert water only while causing heavy siltation in the river with resultant flooding. “Whenever you have a barrage, it obstructs the flow of water and that leads to deposition of silt upstream. So either you have to resort to constant dredging to remove the silt or the problem will persist. Moreover, at the time of floods the barrages are not able to regulate the flow of rivers and in fact become a cause for flooding, even if all their gates are opened.”

So, he said, Kumar is right to demand that Farakka barrage be removed. This, Thakkar said, can be done either physically through the demolition of the barrage or by simply decommissioning it.

As for desiltation along the course of a big river like the Ganga, he said that it was not a practical solution. Nevertheless, Thakkar said the possibility of controlled and monitored removal of sand from the sides of the river could be explored. However, he urged caution in doing so.

Similarly, he said, the national waterways project is also being undertaken across the country and the national waterway 1 is the section of the Ganga from Allahabad to Haldia. While the government wants to keep a depth of 3 metres available along the route for vessels to ply, Thakkar said constant dredging of the river is also bound to cause ecological damage.

Meanwhile, in his blog post on August 23, titled ‘A tale of two dams: Is Bihar’s unprecedented flood an avoidable man-made disaster?‘, Thakkar pointed out that “the unprecedented floods that we are now seeing in Ganga, in Bihar and UP are largely due to contribution of two dams: Bansagar dam, upstream along Sone river in Madhya Pradesh, and Farakka dam (misleadingly called a barrage) on the Ganga river in West Bengal.”

Thakkar said the Farakka barrage did not serve any purpose now. Pointing to the operations of the Farakka ship lock, he wrote that “security personnel there told us hardly any ships pass this route, less than one ship in three months”.

Thakkar said Kumar was right in “asking for an independent review of the usefulness of Farakka barrage and demanding decommissioning of the barrage. He has also rightly asked for a National Silt Management Policy, there is none today. These are very legitimate demands of Bihar chief minister, which he has been raising earlier too, including recently in front of the prime minister, but it seems the central government is not listening.”

The IIT graduate wrote that “today we do not seem to understand or appreciate the role silt and sediment plays in the functioning of our rivers and river basins. This neglect is playing havoc with our rivers and also river basins, right upto fertile plains and deltas, which are shrinking and sinking due to silt not reaching the deltas. So while deltas are deprived of silt that is necessary for their survival, the same silt and sand is creating havoc in the upstream riverbeds and reservoirs.”

Madhuresh Kumar of the National Alliance of People’s Movements also found merit in the Bihar chief minister’s demand that the barrage be demolished and said that “the argument is that a dam has a certain life and once siltation takes place, then they do not serve the same purpose. So if it is removed, the river will find its normal course of flow.” He said that the removal of the barrage would be helpful because every river brings pebbles and silt which flows towards the sea and a delta is formed at the mouth of many rivers. “A dam stops the natural flow and causes deposition of silt, which in normal course would have got distributed over the entire course of the river.”

But if the Farakka barrage would remain, he said, desilting would not be possible. “The only thing that can be done is dredging and that is of key concerns now, when the government has proposed the national waterways project, because on the stretch of the Ganga, due to less flow of water during summer, for ships to move you need dredging and that would lead to destruction of the floodplain and biodiversity. On a small scale it is still okay, but on a large scale if it is done it disturbs the eco-system of the river.”

Shripad Dharmadhikary, a former Narmada Bachao Andolan activist who at present runs the Manthan Adhyayan Kendra, said that while Kumar’s call for the removal of the barrage was okay, desilting the entire river was not practical. “It is not possible really, there will be serious impacts of desilting this large. But in fact what Nitish Kumar is trying to say is that he has been calling for removal of the Farakka barrage to prevent silting to happen at the site. I think that is the only solution which is eco-friendly. We will have to find a way of desilting which will have minimum impact on the river’s eco-system and we will also have to think of removing some of the barrages and other impediments which obstruct the free flow of water and silt. Only that can be a real solution because otherwise silt will accumulate again.”

On whether the removal of barrages was indeed an option, as the government is moving forth with the national waterways project which required maintaining a certain level of water in all parts of the rivers with the help of barrages, Dharmadhikary said, “The problem is that the waterways project is itself going to involve huge dredging and they call it capital dredging and maintenance dredging. The first involves digging up the river to create a deep pathway in the river and then you keep dredging it to maintain the path. The Bihar government has objected to barrages within Bihar and they have said that if you want to build a waterway you do it by dredging in the middle and you build a path. This is very contradictory. The ecological and social impact will be so huge that it is very difficult to choose if you want to build a barrage and destroy a river or you want to dig it up and destroy it.”

On how this balance is managed abroad, he said, “there they have gone to the extreme and are now coming back. In Europe or US they have not only deepened the river, they have channelised most rivers. They concretise the banks and convert it into a virtual canal. But now in many places they are reversing that. What we are saying is that the ideal approach is that water navigation can be an important part of the transport solution of this country but it should be done in a way that it causes minimum interference in the river. So there are natural sections in the river which can be used for transport.”

Dharmadhikary, however, lamented that in a rush to do things, the basic assessments were being overlooked. “To strike that balance, first you have to have an assessment. So if you want to run ships in some part of a river, then you have to look at the tonnage and see the interventions required. But they have not carried out such assessments and they have just decided that this is the depth they want and they want to use machines to make way for the ships. Only now, they have decided to do some environmental impact assessment but it too is piecemeal.”

Stating that the project is huge, he said, there is a push for 101 new waterways, in addition to the five existing ones, and this proposal has been passed by parliament recently. “In the Ganga waterway project, which is National Waterway No. 1 and extends from Allahabad to Haldia, what they have done is that while it is a long waterway, the environmental impact assessments are only being done on certain sections, that is not going to capture the essence or let you know the kind of impact or the assessment of what you should be doing to have minimum environmental damage.”

This approach, he said, is the same as what it has been for the last 50 years that basically you just want this large infrastructure and the environmental assessment and mitigation is only just for the sake of it. “The way the waterways are being planned is one extreme. The other thing is that it is being stated that river transport is very cheap. That is the justification being given in its support. But it is not blanket universal truth. River transport is much cheaper than road transport, but in comparison to rail transport it is not necessarily cheaper. They are saying that if you have ships of a certain tonnage, if they carry a load both ways and if there is a depth of three metres along the route then water transport will be cheaper than the railways, but this is only in specific situations. But we have not seen these documents. Most of these studies are being done post facto.”

On whether removal of silt or sand was an option for not only using rivers as waterways but also controlling floods, Dharmadhikary said, “it can be but it should be done in a manner which preserves the ecological integrity of the river. It should be controlled and monitored.”

Dharmadhikar also cautioned that increase in water transport would come with its own set of problems. “There are many impacts. Pollution, dumping of stuff into the river, oil-leakage and impact of all the dredging and pollution on the fishery and the livelihood of small fishermen. This also needs to be studied but they have not looked it up.”

Unfortunately, he said, the environmentalists have so far not raised these issues collectively. “There has not been a coordinated effort. But in bits and pieces, issues have been raised. In the case of Ganga, some groups have spoken out. We did so in the case of the Mahanadi project. But it has not happened at the level it should have.”