Image and Content Courtesy: Himalmag
Dinesh Kumar Mishra writes about the lessons that are to be learned from the Kosi's history & the consequences when official apathy prevents it. Also in the aptly titled "Finger in the Dike" he details the villager's lack of confidence in the promises of the bureaucrats. This reflects from their rude realization that when the Kosi rises in wrath they will have to face it all alone. A moving article from an expert who sees the problem from all aspects.
Finger in the Dike:
As of mid-November, all arrangements to patch up the massive breach at Kusaha had been completed, and the Kosi River was slated to be brought back completely within its embankments by March 2009. Does this mean that everything will be back to normal at that time? Flood victims are, of course, consoled time and again that there will be no repeat of this year's massive catastrophe. But the Kosi refuses to accept the verdict of engineers and the order of politicians by dutifully returning to its natural floodplain, thus continuing to defy the skills of the former and the powers of the latter to contain it.
Over a hundred years ago, an indigo planter in Purnea District of Bihar named Shillingford observed that the Kosi was prone to swinging like the pendulum of a wall clock between its eastern and western flow boundaries. He warned that it would again bounce back to Purnea from where it was flowing in those days. Since neither scientific nor historical evidence was available at the time to back up Shillingford's warnings, Viceroy George Campbell responded only by saying that one should refrain from making predictions about the Kosi. The only thing that could be said about the river with any certainty, he continued, was that its behaviour was most uncertain. This year, both were proven right.
As it flows from Nepal's hills into the Bihar plains, the Kosi is a meandering river. Over time, it has utilised some 15 different water works, consuming such rivers as the Triyuga and the Bhutahi Balan. It is said that the river once directly joined the Brahmaputra to the far east, at which time it was not a mere tributary of the Ganga. This implies that, at some point in the past, the Mahananda, the Teesta and the Atreyi must have all passed through the channel of the Kosi. The reason for this significant meandering is the tremendous sediment load that comes along with the Kosi's flow, which fills the riverbed and forces the river to seek a different course. It is for this reason that embanking such a river is particularly fraught. After their initial enthusiasm for 'river-taming', British engineers eventually came to oppose any attempt to embank Himalayan rivers, after they realised the difficulty in maintaining embankments, including those constructed at a minimum cost. In 1908, an engineer named Captain F C Hirst publicly stated that embankments were an insult to a river – an insult that would not go un-avenged.
Such pronouncements went unheeded, however. In 1955 and 1963, around 125 km of the Kosi's westernmost channel was embanked, at which point all of the river's water was forced into this waterway. A barrage was also constructed to regulate the flow on the India-Nepal border, located just within Nepali territory. Upstream, barrage bunds were constructed for dozens of kilometres, on both sides of the river. Similarly, dikes were constructed for a hundred kilometres downstream on both sides. In this way, both the waters and the sediment that had traditionally flowed through multiple channels were confined to just one. The large majority of this sediment load subsequently became trapped, leading to a phenomenal rise of the riverbed, to the tune of 10 to 12 cm per year in many places. This inevitably made the embanked channel significantly more destructive than it had been previously: such an elevated river can never remain stable, after all, as it will constantly seek to break free of its shackles.
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