Assam has a history of being affected by floods during the monsoon season every year. The state has a vast network of rivers and is prone to natural disasters like flood, landslides and erosion. There are two major rivers- The Brahmaputra and The Barak. The Brahmaputra is a trans-boundary river which flows through Tibet , North-eastern India, and Bangladesh. It is known as Brahmaputra or Luit. It is the major river of central and south Asia. It flows around 2900 kms( 1800 miles) and has its source in the Himalayas. The river is both a creator and a destroyer—depositing huge quantities of fertile alluvial soil but also causing disastrous and frequent floods.
The tributaries of Brahmaputra namely Subansiri, Ronganadi, Dikrong, Buroi, Borgong, Jiabharali, Dhansiri (North) Puthimari, Manas, Beki, Aie, Sonkosh are the main tributaries on the North while the Noadehing, Buridehing, Desang, Dikhow, Bhogdoi, Dhansiri (South), Kopilli, Kulsi, Krishnai, Dhdhnoi, Jinjiran are the main tributaries on the south bank of the river Brahmaputra. The north Bank Rivers are more steep and braided and generally have more floods.
The Barak River or Barbakro flows 900 kilometres (560 miles) through the states of Manipur, Mizoram and Assam in India. It flows into Bangladesh where it bifurcates into the Surma river and the Kushiyara river which converge again to become the Meghna river before forming the Ganges Delta. Barak river has eight tribuitaries. The Katakhal(Dhaleshwari), Jiri, Chiri, Modhura, Longai, Sonai, Rukni and Singla are the main tributaries of the valley. The tributaries are mainly rain-fed and cause flood problems when heavy precipitation occurs. The Barak sub-basin drains areas in India, Bangladesh and Burma.
The Rastriya Barh Ayog (RBA) assessed the total flood prone area of the state to be nearly 31.05 Lakh Hectares against a total area of state ie 78.523 Lakh Hectacres. Almost every year there is flood in Assam. There is flash floods due to heavy rainfall, cloud burst etc. Breaches of embarkment due to bank erosion is a common phenomenon. This year ie 2024 floods have created havoc in Assam following heavy rainfall after cyclone ‘Remal’ struck and made a landfall near Mongla and Khepupara coasts in Bangladesh and West Bengal in India on 26th May 2024. The situation turned worse when six people died on Friday, May 31, 2024, taking the toll to 10. A total of 560 villages are affected under the 25 revenue circles of Assam.(June1,2024)
The storm surge was accompanied by extremely heavy rainfall and wrecked havoc. It brought heavy rains in various parts of Assam and Manipur. This caused the first flood in Assam in May 2024 and then within a span of one month the second flood stuck. According to Assam Disaster Management Authority (ASDMA) 1,05,786 people living in 309 villages across 14 villages of Assam were affected by the floods. 95315 alone in Karimganj district were affected. Over 3000 people had to take shelter in relief camps. Karimganj was worst hit followed by Nagaon and Dhemaji. Embarkments, roads, bridges and other infrastructure have been damaged by floodwaters in several districts. Crops in large areas have been damaged across the state along with domestic animals. This year Majuli also witnessed flash floods from River Subansiri because of heavy rainfall in Arunachal Pradesh from where the river flows steeply into Assam. Heavy rainfall in Arunachal Pradesh and Bhutan caused flooding in Assam. River bank erosion is a significant problem in the floodplains of alluvial rivers. The Barak river has experienced severe erosion of its banks resulting in loss of human habitation and property. The most erodible sites are Sonai, Tarapur Nathpara and Panchgram. Serious measures need to be taken to stop erosion. Several incidents have taken place during the recent floods where houses have been washed away due to erosion of banks.
The overflowing Kopili river flooded large area of Hojai. 14 districts of Assam have been affected-Tamulpur,Bongaigoan, Karimganj, Lakhimpur, Udalgiri, Darang, Dhemaji, Nagoan, Hojai, Barpeta, Chirang, Baksa, Nalbari and Goalpara were most affected.
Number of human lives lost in this year’s flood, landslide, storm and lightening has reached 109. Flood water is receding in almost all the inundated areas of the state but the damage and loss of property has remained a serious issue. According to The Hindu ,July,10, 2024 flood situation has improved marginally with water levels of major rivers receding.
Encroachment of wetlands and the natural drainage system are the main reasons of flooding. The floods of 2022 are still fresh in the minds of the people and brings back terrible memories. According to sources the breaches of embarkment are to be blamed along with non repair and poor maintenance of the embarkments before the onset of monsoon.
Major cities like Guwahati, Silchar, and Karimganj were struggling with urban floods caused by water logging following heavy rainfall. Most of the urban floods are due to improper drainage and improper waste disposal . Most of the khals or drains are blocked due to garbage dumped into the khals which block the flow of water and result in flooding.
Kaziranga National Park has been affected with death of 159 wild animals due to drowning while 133 have been saved. According to Indian Express, July 1, 2024, prohibitory orders on movement of traffic on NH 37 have been placed to protect wildlife. Under section 163 of Bharatiya Nagarik Suraksha Sanhita (BNSS) movement of vehicular traffic has been restricted and speed limit has been imposed between 20 and 40 km/hr. According to the field director of KNP 104 hogdeers, 6 rhinos, 2 Sambars have died due to drowning. One otter pup died and several are under care. Forest department employees are staying in the camps inside the national park to conduct patrols for protection of flora and fauna. 63 hog deers, 2 otters, 2 scops owl, one rhino calf, one Indian hare and one jungle cat were rescued. 26 animals are under treatment and 29 animals have been released after recovery. Out of the total 233 camps in Eastern Assam Wildlife Division 141 are still under water, in the eastern range 21 out of 34 camps are inundated while in Western range 33 out of 39 are inundated ,25 in Burapahar and 3 of 9 in Bokaghat are under water.
Tackling floods:
Human folly and ignorance is responsible many a times for floods like the tributary Beki of Brahmaputra , changing course and displacing thousands of people. The river Beki a tributary of Brahmaputra changed course and displaced large number of people, thousands from 222 villages in Kalgchia and adjoining areas were marooned by the river. The river Beki carries 80 % of silt load of two rivers- Manas and itself ie Beki and flows into the Brahmaputra. The river has a meandering course and changed its course and also caused severe erosion of the bank. Any type of construction needs to have proper planning and feasibility considering the environmental conditions. The situation also was aggravated due to the excess water released from Kurichhu dam in Bhutan.
Another important cause of floods is the lack of coordination between the different departments. Repair works commence only after monsoon in and this only creates problem which affects large number of people living on the banks of the rivers. The administration has to start work during dry season much before monsoon sets in and repair work has to be undertaken before the commencement of rain. Controlling of erosion of river bank is essential. Roads and railway tracks get washed away causing misery to people. Proper assessment and planning has to be done before taking up any infrastructural work like building drainage in towns and cities.
Urban planning is essential and urban planners need to be foresighted in designing the towns and cities. There must be expertise and futuristic thoughts to enable proper designing. Garbage disposal is another very important aspect in regards to urban flooding. Daily garbage collection and segregation at source needs to be done to ensure proper disposal. Dumping in haphazard manner creates problem. The administration has to ensure proper and scientific method of waste disposal so as to ensure proper flow of water. Storm water drainage needs to be developed with proper planning and execution. Encroachment of drains needs to be cleared so as to ensure proper and continuous flow of water. That will safeguard against flooding due to sudden heavy rainfall.
Rising and strengthening of embarkments along the riverbanks needs to be done so as to prevent flooding. Protection by using Geobags along erosion prone sites is essential. The causes of floods are many and needs proper planning and execution. Floods are natural calamities and bring in lots of destruction, damage and loss to public property and create a lot of misery. It needs to be handled and tackled judiciously involving government departments, the general public, farmers, forest personals and others. It also needs funds for meeting all the expenditure and requires dedication and commitment, only then will people be saved from misery, loss of live and property every year.
References:
1 Assam floods 2024: Unprecedented timing and fury grips state
Published on 4th July 2024
2 Indian Express 9th July 2024
3. The Hindu 11th July 2024
4.Relief web, I June ,2024
(The article is solely the opinion of the author. The views expressed here are solely personal and not in any way connected to any organisation or any political party.)
Professor (Retired), Dept of Ecology and Environmental Science, Assam University, Silchar-788011
Email id: deymithra57@gmail.com