Is it natural for a river to shift course? What rights, if any, do the displaced people have? How can India check its surging rivers? TOI finds the answers
When the Kosi reverted to its 250-year-old course last month, leaving 30 lakh people homeless in northern Bihar, apparently due to heavy rains in Nepal, the near-Biblical scenes of havoc left many with just one question: Why?
Why do rivers change course? What happens to the people they displace? Are these refugees of wayward rivers entitled to compensation for the land they lost? And just how prepared is India to check its surging rivers? It’s futile to ask ‘why’, says A K Bajaj, chairman of the Central Water Commission because “it’s very natural for a river to keep shifting its course. It’s a part of its natural evolution.” Bajaj explains that fast-flowing rivers are prone to silting up as they surge down the hills and spread out on the plains, allowing sand and suspended matter to deposit in their slower, wider depths. Over time, the deposits create resistance, forcing the river to move to an area of lower resistance. This is called changing course. Nature’s fury—earthquakes, landslides, hurricanes—can change a river’s course as well.
And then there’s man. Environmentalists now say at least some of the blame lies with human activity. Says IPCC chief R K Pachauri, “As a result of climate change, floods are increasing in frequency and intensity. It’s not possible to ascribe a single event such as the current floods in Bihar to human-induced climate change, but the trend is unmistakable.
These are likely to get more serious in the future if the emissions of greenhouse gases are not mitigated at the global level.” Bajaj agrees that “the volume of water in rivers has been on the rise, resulting in greater force of flow. Therefore, even relatively lesser amount of rain during the monsoon can lead to a catastrophe”. He adds that “in the next 15-20 years, this phenomenon will continue till most of the glaciers have melted.
After that, there will be just minimal flow of water.” The role of natural evolution and nature’s fury in a river changing course may sound like one of the simplest lessons in a child’s geography book. But the effects can be complex. When waterside property suddenly becomes landlocked for miles and new waterfront acreage emerges, havoc ensues. Who owns the new land? Do the people who once farmed along the banks have any rights at all? The government has a 54-year-old formula by which land equivalent to 3.5 times the width of the river on either side is deemed the floodplain.
Embankments are built on it. If a river has changed course, the new floodplain “is considered very fertile and good for farming although this stretch is never safe from floods,” says Bajaj. People want to settle on the floodplain because it is fertile and easily irrigated. Not so the Kosi, the river of sorrow, which brings unfertile soil with it from the higher reaches. Authorities say that once the Kosi waters start receding, the breach in Nepal would be repaired. It is hoped that the river would revert to its original course.
If that happens, the question is whether it would be possible to reclaim the 2.75 lakh acres of farmland, that are under water now. The Kosi has forced public policy review before. It caused devastating floods in 1953-54, forcing the government to announce zoning to demarcate areas prone to flooding. An estimated 40 million hectares across India were classified flood-prone. But 54 years later, less than half are protected by embankments. “Issues like topography, policies and other factors cause delay.
In Upper Assam, for example, we are witnessing rising levels of the Brahmaputra and its tributaries in Dibrugarh district. But the river is so huge and ferocious that it’s very difficult to tame it,” says a CWC official. Officials at the department of hydrology studies say that building dams may be the best way out, as is the case with the Colorado river in the US. It has 30 dams to keep it in check. “In case of the Ganga and the Kosi, the government of Nepal, where both rivers originate, is not allowing construction of dams.
So, we shall remain at perpetual risk,” says Bajaj. It is true that dams have become a symbol of development at great human cost. Environmentalists protest against them. But officials say, “Either you protect human lives or you protect each and every plant and animal on this earth and negate human beings and their development.” IN DANGEROUS WATERS The Kosi river in north Bihar is notorious for the meandering behaviour of its east-to-west course. In the past 250 years, the Kosi has moved westwards by more than 100 km Bihar has a history of rivers changing course because of its terrain.
he Ganga has been changing its course over the years and last year, a new 500-acre tract came into existence between Maner and Mokama. Ownership of this tract became a bone of contention between some landlords in the area The Brahmaputra has a huge volume of water and is quite unmanageable. It keeps changing course and a major shift has been observed in the North-East since the 1960s The Rupnarayan river in West Bengal joins the Hooghly after completing a 240-km course.
It carries huge silt deposits and may be forcing the Hooghly to shift course Areas of Uttarakhand, which are near the foothills, are at risk because the Ganga can change course The Sone river in central India has been notorious for changing course, as is evident from several old beds on its east. In modern times this tendency has been checked with the anicut at Dehri, and now more so with the Indrapuri barrage There is evidence of a steady westward shift in the course of the Indus since pre-historic times
When the Kosi reverted to its 250-year-old course last month, leaving 30 lakh people homeless in northern Bihar, apparently due to heavy rains in Nepal, the near-Biblical scenes of havoc left many with just one question: Why?
Why do rivers change course? What happens to the people they displace? Are these refugees of wayward rivers entitled to compensation for the land they lost? And just how prepared is India to check its surging rivers? It’s futile to ask ‘why’, says A K Bajaj, chairman of the Central Water Commission because “it’s very natural for a river to keep shifting its course. It’s a part of its natural evolution.” Bajaj explains that fast-flowing rivers are prone to silting up as they surge down the hills and spread out on the plains, allowing sand and suspended matter to deposit in their slower, wider depths. Over time, the deposits create resistance, forcing the river to move to an area of lower resistance. This is called changing course. Nature’s fury—earthquakes, landslides, hurricanes—can change a river’s course as well.
And then there’s man. Environmentalists now say at least some of the blame lies with human activity. Says IPCC chief R K Pachauri, “As a result of climate change, floods are increasing in frequency and intensity. It’s not possible to ascribe a single event such as the current floods in Bihar to human-induced climate change, but the trend is unmistakable.
These are likely to get more serious in the future if the emissions of greenhouse gases are not mitigated at the global level.” Bajaj agrees that “the volume of water in rivers has been on the rise, resulting in greater force of flow. Therefore, even relatively lesser amount of rain during the monsoon can lead to a catastrophe”. He adds that “in the next 15-20 years, this phenomenon will continue till most of the glaciers have melted.
After that, there will be just minimal flow of water.” The role of natural evolution and nature’s fury in a river changing course may sound like one of the simplest lessons in a child’s geography book. But the effects can be complex. When waterside property suddenly becomes landlocked for miles and new waterfront acreage emerges, havoc ensues. Who owns the new land? Do the people who once farmed along the banks have any rights at all? The government has a 54-year-old formula by which land equivalent to 3.5 times the width of the river on either side is deemed the floodplain.
Embankments are built on it. If a river has changed course, the new floodplain “is considered very fertile and good for farming although this stretch is never safe from floods,” says Bajaj. People want to settle on the floodplain because it is fertile and easily irrigated. Not so the Kosi, the river of sorrow, which brings unfertile soil with it from the higher reaches. Authorities say that once the Kosi waters start receding, the breach in Nepal would be repaired. It is hoped that the river would revert to its original course.
If that happens, the question is whether it would be possible to reclaim the 2.75 lakh acres of farmland, that are under water now. The Kosi has forced public policy review before. It caused devastating floods in 1953-54, forcing the government to announce zoning to demarcate areas prone to flooding. An estimated 40 million hectares across India were classified flood-prone. But 54 years later, less than half are protected by embankments. “Issues like topography, policies and other factors cause delay.
In Upper Assam, for example, we are witnessing rising levels of the Brahmaputra and its tributaries in Dibrugarh district. But the river is so huge and ferocious that it’s very difficult to tame it,” says a CWC official. Officials at the department of hydrology studies say that building dams may be the best way out, as is the case with the Colorado river in the US. It has 30 dams to keep it in check. “In case of the Ganga and the Kosi, the government of Nepal, where both rivers originate, is not allowing construction of dams.
So, we shall remain at perpetual risk,” says Bajaj. It is true that dams have become a symbol of development at great human cost. Environmentalists protest against them. But officials say, “Either you protect human lives or you protect each and every plant and animal on this earth and negate human beings and their development.” IN DANGEROUS WATERS The Kosi river in north Bihar is notorious for the meandering behaviour of its east-to-west course. In the past 250 years, the Kosi has moved westwards by more than 100 km Bihar has a history of rivers changing course because of its terrain.
he Ganga has been changing its course over the years and last year, a new 500-acre tract came into existence between Maner and Mokama. Ownership of this tract became a bone of contention between some landlords in the area The Brahmaputra has a huge volume of water and is quite unmanageable. It keeps changing course and a major shift has been observed in the North-East since the 1960s The Rupnarayan river in West Bengal joins the Hooghly after completing a 240-km course.
It carries huge silt deposits and may be forcing the Hooghly to shift course Areas of Uttarakhand, which are near the foothills, are at risk because the Ganga can change course The Sone river in central India has been notorious for changing course, as is evident from several old beds on its east. In modern times this tendency has been checked with the anicut at Dehri, and now more so with the Indrapuri barrage There is evidence of a steady westward shift in the course of the Indus since pre-historic times
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