Floods have swamped Assam again. Just like last year. And the years before that.
More than half of the state’s population has already been hit. At least 23 people have died, and thousands have been displaced already – as of Saturday evening, almost 17,000 people have been lodged in the 188 relief camps across the state. These are only official statistics. The actual number of affected people is likely to be much higher.
The floods arrive in Assam each year like clockwork. Widespread damage and displacement follows. All of this is marked by a sense of helplessness on part of the state machinery. “Whenever we take one step forward towards development, floods and erosion push us two steps backwards,” Assam’s chief secretary VK Pipersenia told The Indian Express last year, hinting at the government’s powerlessness against the fury of the Brahmaputra.
So, is Assam’s fight against the floods that ravage its plains every year akin to battling nature’s brute force against whom even the most cutting edge research and science often fall short?
A river that cannot be tamed
There is a consensus that the Brahmaputra is indeed a difficult river to tame. It is arguably the most heavily sediment-charged river of its size in the world. Add to that, the peculiar topography of the region: Assam’s floodplains are surrounded by hills on almost all sides. The gradient of the river can be as steep as 16.8 metres per kilometre in the hills of Arunachal Pradesh, but as it reaches Assam’s capital, Guwahati, it is as low as 0.1 metres per kilometre. This dramatic reduction in the gradient results in the river unloading large amounts of sediments in the valley, which can lead to violent floods and erosion.
The mega river also has a complex and dense network of tributaries, most of which are bigger than most rivers elsewhere in India.
‘Floods natural, damage man-made’
But experts contend that while taming the river may indeed be next to impossible, the extent of damage can certainly be contained. “Floods are natural, but the damage man-made,” said environmentalist Dulal Chandra Goswami, considered one of the foremost authorities on the Brahmaputra. “Our approach to the flood problem has always been piecemeal,” he said. “A lot of agencies work on it, but there is no coordination among them.”
According to Goswami, the only way forward is what he calls “integrated basin management”. This can be defined as the coordinated management of natural resources like soil and forests in the river basin – the portion of land that is drained by a river and its tributaries – along with the water. “The river basin has to be taken as the basic planning and development unit,” explained Goswami. “It is quite simple actually. You have to deal with the problem at the source – the basins. There has to be active and intense afforestation there to reduce surface run-off as much as possible.”
However, that may be easier said than done. The river basin of the Brahmaputra spreads across Tibet, India, Bhutan and Bangladesh, with the largest catchment area in Tibet. In India, the basin is spread across several states including Assam, Arunachal Pradesh and Nagaland. These states do not share the most amicable relationship regarding the river. “The river does not understand or respect political boundaries,” said Goswami. “It is for politicians to sit together and formulate some sort of compromise. This fractured nature of planning must go. You cannot deal with a problem as big as this with seasonal planning.”
The Brahmaputra Board, a central government agency located in Guwahati, is mandated to formulate master plans for the river in relation to a host of activities including flood control. Its officials claim that talks with the Arunachal Pradesh government in the past have been futile. “We believe the only permanent solution is to build massive storage reservoirs on the upstream of the river and its main tributaries,” said a senior-level official of the board, who did not want to be identified. “The problem [of flooding] would have been solved by now if not for the objections of Arunachal Pradesh who fear some of their towns may get submerged.”
The technocrat claimed that Arunachal Pradesh’s fears were more “political than scientific”. “We had proposed this a long time back, and the displacement would have been minimal,” he claimed. “But it seems in a state like Arunachal Pradesh, where Assembly constituencies often comprise 2,000 people, politicians were apprehensive it would hurt their vote base.”
To engineer or not?
Goswami, however, said that reservoirs may not be the best way forward as drastic technological-engineering interventions could backfire. “We have not tried most basic things like watershed management and reviving the many wetlands of the state properly,” said Goswami. “Also, many of the perennial tributaries of the Brahamaputra and seasonal ones have become non-existent. They are important channels for the water to go, we must revive them. Sustainable solutions that actually address the problem should be the way ahead, structural elements should be kept to the bare minimum.”
Assam has almost 3,500 wetlands that are like natural safety valves against floods because of their water-holding capacity. However, most of them are as good as dead now with very little capacity owing to encroachment and construction activities.
The debate about embankments
Engineering interventions have yielded mixed results so far. Embankments, the most widely used go-to defence against floods, have often been blamed for being counter-productive and exacerbating problems. The complaint heavily draws upon the fact that embankments in Assam are routinely breached with catastrophic consequences when it floods.
But there is also a strand of thought that claims embankments provide a much-needed safety net for vulnerable sections of society.
Kalyan Das, a social scientist at the Guwahati-based Omeo Kumar Das Institute of Social Change and Development, said that he has experienced “several success stories” concerning embankments during his field trips. “Common people perceive it as safe,” said Das. “Also, there is a political demand for it. The embankment is often used as a road of sorts by people in low-lying areas. It is an open-ended debate.”
Das claimed another reason that made the embankments indispensable was pressure on land. “There used to be a time when people would completely avoid low-lying lands,” he explained. “But that is just not possible anymore with increasing population and crunch of land. Economically and socially disadvantaged people often settle in low-lying areas and the embankments are necessary for their safety.”
A Brahmaputra Board official said that embankments were only supposed to be a “temporary measure” after the water level in the river rose drastically in the aftermath of a massive earthquake that struck Assam in 1951. “But they stayed on for a host of political reasons,” he said. The official conceded that the embankments were not maintained well, blaming the lack of funds for this. “Also, the soil is such that it gives way very soon, and there is very little we can do about that.”
Manabendra Saharia, a post-doctoral researcher at the United States-based National Center for Atmospheric Research, suggested rockfill embankment dams as an alternative to earthfill dams, the most commonly found variety in Assam. “A rockfill dam is filled with at least 50% rock and are an economical and sturdy alternative,” he said.
Rockfill dam embankments primarily comprise compacted rock materials, which provide an effective barrier against the flow of rivers.
Additionally, Saharia emphasised the need to have more robust flood prediction mechanisms. There is a lack of a cohesive forecasting model due to bureaucratic red tape, he said. “Sometimes, it takes months and years to even get historical [rainfall and river flow] data, most of which have to be paid for despite these data being collected by government [agencies] using public taxes.”
“Flooding in Assam does not require an engineering miracle, but application of civil engineering tools that have been tested and recommended,” added Saharia.