“The river was swollen the morning after the earthquake, which seemed to last for an eternity. We saw fallen trees in it, people and animals flailing, dead bodies of people and animals that were carried on the strong current.”
Krishna Chawla (née Das) was 13 when a strong earthquake that lasted about eight minutes jolted Assam and adjacent areas on the evening of August 15, 1950.
The Brahmaputra River, which was always “eating away at parts of the state,” looked terrifying, she recollects. “All of us students went to help build embankments the next day, and while I was passing a bag full of sand to a fellow student, I saw the river take away the house I was born in. The house collapsed, and I stood there paralysed,” said Ms. Chawla, the daughter of a forest officer in Dibrugarh.
The massive earthquake that ravaged Assam on Independence Day that year not only claimed over 1,000 lives, but also changed the course of the mighty Brahmaputra. The riverbed rose as the mountains shook, and what had been a stable course became a constantly shifting one eroding the banks.
This especially increased the amount of silt carried by the river and its tributaries. The silt was deposited on the banks downstream, and on the riverbed. Due to this heavy deposition, the river "frequently changes its course with the main channel flowing into multiple channels" hitting the river bank causing further erosion, a study published in 2014 by the Civil Engineering Department, Royal Group of Institutions explains.
The riverbed area of the Brahmaputra has increased by more than 50 per cent through erosion since the quake. According to a report on climate change published by the government of Assam in September 2015, erosion has destroyed more than 3,800 square kilometres of farmland, which is nearly half the size of Sikkim, since 1954. Due to erosion, the riverbed area has expanded from around 3,870 sq.km. estimated between 1916 and 1928 to 6,080 sq.km. in 2006. Based on the civil engineering report, between 1954 and 2008 about 4,27,000 hectares has been eroded at the rate of 8,000 hectares per year.
The human cost
Lalita Biswas, 30, a daily wage earner at a brick factory in Morigaon, Assam, had to leave her submerged house in a village in Morigaon in a boat provided by villagers and take shelter in an open space on a nearby hillock. She was living in a polythene tent with her husband, who also works at the brick factory, and children. Her children have suffered from colds and fevers, and her family did not receive any help from the government, she said.
“We’re always neglected because we are poor,” she said when asked if she had received any help from the state authorities. Ms. Biswas wasn’t alone. About 100 people climbed the hills to escape the flood and have to rebuild their houses and lives.
A similar story was told by Nishikant Deka, 80, of Gorubandha, a village about 40 km from Guwahati. He and his 12-member family had to evacuate their house in neck-deep water and take shelter at a naamghar (public prayer hall). They managed to carry some rice, and food provided once in a while by NGOs kept them going. The head of the house described how almost every year the family has to reconstruct the bamboo home that floodwaters destroy.
The government of Assam estimates that 2,753 human lives have been lost along with 6,73,329 cattle and the total losses due to floods and erosion amount to nearly ₹4659.472 crore. Flooding this year took the lives of 157 people and destroyed hundreds of acres of land. According to the state disaster management authorities, in the past five years, flooding has killed about 500 people.
Controlling the floods
One of the main methods used in the State to control floods is embankments, but almost every year the Brahmaputra and the Barak breach their banks, inundating agricultural land and houses. “The most recent embankments are 25 years old,” says Himanshu Thakkar, coordinator of the South Asia Network on Dams, Rivers and People. “Checking embankments before monsoon should be done as we never know where it will be breached. When the flow is extreme, erosion capacity is greater,” he adds.
In August this year, the State government announced that as many as five dredgers will be used to deepen the Brahmaputra, and the harvested silt will be used to construct the 725-km Brahmaputra Expressway along both banks of the river. In an earlier report , the Chief Minister Sarbananda Sonowal told The Hindu : “We believe it will not only improve the water-carrying capacity of the Brahmaputra, but also make the river navigable for bigger cargo ships. That used to be the case before Independence.”
Sanjoy Hazarika, director of the Commonwealth Human Rights Initiative is unconvinced. He is for an engineering assessment, along with environment assessment, as dredging “might change the course of river.” Mr. Thakkar adds that the way dredging is done followed by the construction of highway on both banks will determine the changes the river will see.
The Brahmaputra Board, under the Ministry of Water Resources, had suggested constructing dams in Assam and Arunachal Pradesh about 30 years ago, the Subansiri project being one of them. Subansiri was initially designed as a hydro-power and storage dam, which the board believed would help reduce the impact of floods. However, it was later transformed into just a hydroelectric project aimed at generating 2000 megawatts of electricity, which invited opposition from local people and environment scientists.
There is the possibility that hydro electric projects can worsen the situation. “Ranganadi project is a classic example of damage caused by the dam in downstream,” Mr. Thakkar points out. The dam in Arunachal Pradesh -- part of a hydro-electric project -- is on the Ranganadi tributary of Brahmaputra. During winter the river barely exists, but during monsoon it swells up, inundating villages. The All Assam Students' Union in July this year demanded demolition of the Ranganadi hydro project, alleging that release of water by the North Eastern Electric Power Corp. on July 11 without prior notice affected hundreds of thousands of people in Lakhimpur and Majuli, media reported.
The permanent destruction of wetlands in the State has also been contributing to the deluge. Assam is home to more than 3,000 wetlands and many varieties of flora and fauna. “Wetlands, locally known as beels, act as reservoirs and rejuvenating them before monsoon can help in mitigating flood in parts of the state,” said Dulal Chandra Goswami, former head of department of environmental science at Guwahati University.
“Wetlands play a very significant role as natural reservoirs of water that absorb part of the flood waters from the nearby rivers through their connected channels and also from surface runoff," Mr. Goswami explains. Most of these wetlands are in derelict condition mainly due to human-induced factors such as encroachment for agriculture or infrastructure development.
“To mitigate floods, any potential practical solution should be based on an integrated, multidisciplinary basin management plan focused on water and soil conservation together with geo-environmental, eco-biological and socio-cultural integrity of the basin,” Mr. Goswami says. “The basin management approach is essential in view of the interstate as well as international character of most of the tributaries and the mainstream.”
Effects of Climate Change
Compounding the issue of an unpredictable Brahmaputra, are the effects of climate change. “Climate change will result in more frequent and severe floods, which will increase the costs of reconstruction and maintenance on state infrastructure, including roads, irrigation, water and sanitation,” says the report on climate change published by the Assam government.
According to the study, by 2050, the average annual runoff of the river Brahmaputra will decline by 14 per cent. However, there is a risk of glaciers melting, leading to flash floods.
As the economy of Assam is largely dependent on natural resources, what happens with agriculture and forests has direct effects on the livelihood of its people. During floods, water becomes contaminated, and climate change has a direct impact on the water resources sector by increasing the scarcity of freshwater, which is a constant problem in summer.
“The predicted increase in average temperature and decrease in the number of rainy days due to climate change will further stress water resources,” the report points out.
The study goes on to say that heavier rainfall replacing continuous low or normal rainfall during monsoon might lead to flash floods in low-lying areas. This will also reduce the groundwater recharge.
Change in approach
While the present approach towards flood has been immediate relief, much more need to be done before torrential rains hit the State during monsoon. The short-term measures on which flood management in the State presently depends, such as rebuilding the breached embankments, are largely inadequate.
Besides, more accurate and decentralised forecasts of rain can help in improving preparedness. “Weather reports should be made available on district level and should be accessible to public,” says Mr. Thakkar of the South Asia Network on Dams, Rivers and People. “Information should be available in local languages. With the forecast in, one can calculate how much more water will flow downstream, thereby alerting people in advance to evacuate. The nature of rivers is such that there is no way one can flood-proof whole of Assam so one has to keep it mind that floods will happen.”
He adds that the water flow information shared by China on the Brahmaputra with India, for which India pays a certain amount, should also be shared with the public, as this will help in understanding the river better and therefore help people better prepare for floods.
As the research scholars point out, studying the river and the impact of climate change is a must to understand why the state gets flooded every year. As line in a famous Assamese song goes: “ Luitar parore ami deka lora; moribole bhoi nai (We are the youths from the banks of the Luit [Brahmaputra]; we are not afraid of death),” people in the Valley seems to be living by the same spirit.