INEVITABLE FLOODS IN ASSAM

Floods in Assam have become more severe and frequent, affecting over 2.5 million people across 30 districts this year. The Assam flood crisis has been escalating, with heavy rainfall becoming the norm in the region. Over the past seven decades, human interventions, such as embankments, encroachments, and deforestation, have worsened these floods. 

HISTORY & IMPACT:

* Historical data shows a rising trend of flood impacts, with the average annual flooded area and affected cropland increasing from the 1950s to the early 2000s. The number of affected people surged from 860,000 to over 4.5 mn, and economic damages increased more than 120-fold annually. 

* The intensity and destruction have increased since the great earthquake of August 15, 1950, which disturbed the courses of many rivers. 

* Since the 1950s, Assam has built 423 embankments along the Brahmaputra River and its tributaries, with 295 outlived their intended lifespan, causing regular breaches, damage, and destruction. 

* The 2004 devastating flood damaged 2000 bridges, 622 km of National Highways, 212 human lives, and took many lives, causing 1223851.17 hectares of agricultural land, with 6888909 hectares damaged.

* Again in Oct 2004, a sudden flash flood occurred in the south Goalpara plain due to overflow of Jinari and Krishnai rivers from Garo hills. The same phenomenon occurred in 2014 as well, a decade later. Human-induced causes, such as vegetation destruction in the northern slopes of Garo Hills and construction of railway lines, significantly intensified the disaster.

* Major floods have occurred in the region in various years, with annual flash floods and long-term inundations occurring in 2018, 2020, 2021, 2022, and 2024. 

* In 2017, 160 human deaths were reported, 122 in 2020, and 102 in 2019. In 2024, 2.45 million people were affected across 30 districts, with 52 flood-related deaths.

* The Assam State Disaster Management Authority(ASDMA) reported 838 deaths in floods from 2013 to 2022, with the highest death toll in a decade in 2022. In 2022, Cachar district was among the worst affected, with over 500,000 people impacted. 

* Dhubri, where two rivers meet, saw over 775,000 people affected in 2022, while Barpeta had over 1 million. Morigaon, close to the Brahmaputra River, is one of the worst-hit areas. Cachar, in southern Assam, affected over 500,000 people in 2022. 

* Assam faces severe flooding in several districts with 4-5 floods every year, including Dhubri, Barpeta, Morigaon, Cachar, Darrang, Goalpara, and Lakhimpur. Darrang, in northern Assam, sees hundreds of thousands affected annually. Goalpara faces flash floods from hills and river flooding, while Lakhimpur faces flooding from local rivers. These districts highlight the need for long-term flood mitigation strategies.

* Recent studies showed increasing pre-monsoon and monsoon rainfall in Assam, while post-monsoon and winter rainfall showed decreasing trends. 

VULNERABILITY

* According to the Climate Vulnerability Index developed by the Council on Energy, Environment and Water (CEEW), Assam, Andhra Pradesh, Maharashtra, Karnataka, and Bihar are highly vulnerable to extreme climate events such as floods, droughts and cyclones.

* A vulnerability analysis of flood vulnerability in Assam reveals complex risk and preparedness patterns. With more than 40 percent of Assam’s land surface susceptible to flood damage, the total flood-prone area in the Brahmaputra valley is about 3.2 Mha

* Barpeta district has a high susceptibility to flood impacts, while Sarthebari and Kalgachia have high flood impact scores but lower vulnerability, indicating better resilience. 

* Nalbari and Nagaon districts have moderate flood impact and vulnerability scores, suggesting a balanced situation. Preparedness levels are high, but high preparedness doesn't always correlate with lower vulnerability scores.

REASONS

* Climate activists emphasized that the region's existing infrastructure is not equipped to handle such weather anomalies. Floods and erosion often force people into daily wage labor or drive migration to cities, where men often find work in hotels and restaurants, while women have fewer and more restricted options.

* The Brahmaputra River flows through Arunachal Pradesh and Assam before emptying into the Bay of Bengal. This river system, vital for the region's ecology and economy, makes Assam susceptible to annual flooding. The Brahmaputra valley, which has over 50 tributaries, is influenced by melting glaciers during summer and heavy monsoons, causing overflow. The majority of flood flows are generated in India, with the Yarlung Tsangpo conveying snowmelt streamflow from Himalayan glaciers. 

* The average annual rainfall in North East India is very high varying between 100cm and 1300 cm. Besides, about 80% of the annual rainfall comes mainly in the 5 summer months from May to September. This is also the period when the snow over the Himalayas melts and the water from there rolls down to rivers. Thus making the supply of water excessive which inundates the neighbouring areas.

* Low gradient of the plain areas which makes the excessive rain and snow melt water to flow down the plain areas causing flood.

* Each of the Brahmaputra and Barak plain is surrounded by 3 sides by hills and mountains. So, water rushes down to the plain from the extensive catchment areas causing flood

* The catchment areas of the Brahmaputra and Barak river except Meghalaya are made of soft tertiary rock. The heavy monsoon rain that fall on them further soften the materials causing solifluction, sheet erosion and landslide down the steep slopes causing to blockage of the river stream. Thus the riverbeds are choked. Water therefore overflows the channels causing floods. Further the great earthquake of Assam in August 15 1950 raised the beds of Brahmaputra, Dibam, Lohit, Subansiri and many other rivers. The rising of the bed naturally reduced the volume of the channels making the rivers shallow thus causing to floods.

* Silt from high-altitude areas forms sandbanks and islands, and settlements have developed in these areas, obstructing the river's natural path. 

* Deforestation is the primary factor in worsening floods in Assam, as it drives soil erosion and exposes land to weather. Deforestation in the Eastern Himalayas has reduced the soil's rainwater absorption capacity, increasing surface runoff and soil erosion, amplifying flood impacts, making the region susceptible to being washed or blown away. 

* With the rapid increase of population and technological development, man has been indiscriminately cutting the forest cover leading to losing of the soil profile, which is rapidly washed down by the streams and rivers which get deposited on the channel.

* Climate change is causing Assam to experience increased floods due to factors such as river-bank erosion, wetland degradation, deforestation, and unsustainable riverbed mining. Rising global temperatures intensify the monsoon and extreme rainfall, impacting Assam as well. Environmentalists states that climate change makes the monsoon erratic and intense, overwhelming Assam's rivers. 

* Dam-induced flash floods from hydropower projects also occur annually. Erosion has reduced riverbed capacity, leading to overflowing rainfall and frequent breaches of embankments. 

* The loss of wetlands as natural flood barriers and hazard construction in floodplains obstruct natural drainage, worsening urban flooding.

INITIATIVES:

* Flood management in Assam is hindered by a lack of robust alert mechanisms and limited inter-state and international cooperation, which contributes to the vulnerability of communities to sudden inundations. 

* The Flood Control Department of Assam has so far constructed 984 km of embankments on the banks of Brahmaputra, 2,567 km of embankments on its tributaries, 600 km of the drainage canal, 56 sluice gates, and 421 bank protection spurs.

* In 1981, the Brahmaputra Board was reconstructed to control bank erosion, produce hydro-electricity, and irrigate agricultural land. The board also constructed a dam across the Barak River at Tipaimukh, aiming to control floods in Assam, Manipur, and Mizoram.

* The Assam State Disaster Management Authority (ASDMA) has collaborated with tech initiatives like CivicDataLab to develop data models for improved flood preparedness and response.

* The Chief Minister's Climate Resilient Village Fellowship Programme in Assam aims to raise climate change awareness and empower younger generations. It involves graduate and postgraduate students from science and engineering institutions, who are assigned villages to study and recommend climate-resilient solutions. This initiative aims to empower climate-smart leaders.

* In 2023, Assam introduced a 'green budget' for climate change action and disaster risk reduction. 

* However, despite annual funds and resources, Assam struggles to manage its floods due to the disrepair of decades-old flood control structures and a lack of long-term planning. 

* Floods often prompt short-term rescue and relief, leading to a perception of these events as normal for Assam, despite increasing flood frequency and intensity.

CONCLUSION

Assam faces natural hazards like floods, riverbank erosion, drought, and earthquakes, exacerbated by geography, topography, and climate. Human activities like deforestation and dam construction have intensified these hazards. Flood management in Assam is hindered by lack of robust alert mechanisms and limited cooperation. Despite many initiatives Assam still struggles to manage floods due to disrepair of control structures and lack of long-term planning.