The Flood Situation of Assam A Case Study

Transcription

1 Abstract The Flood Situation of Assam A Case Study Mukul Chandra Bora Lecturer (Sélection Grade) in Civil Engineering Dibrugarh Polytechnic, Lahowal: Pin: Assam, India The problem caused by water may broadly be catagorised into two major groups viz. shortage of water and surplus of water. Shortage of water causes drought and surplus water causes flood. The water is the vital ingredients for the survival of human being but sometimes it may cause woe to the human life not due to insufficient water but due to abundant water which in turn causes the natural disaster called as flood. Assam is situated at the easternmost part of India. Geographically it is at the foothills of the Himalaya. Every year Assam experiences a huge amount of losses due to devastating flood caused by the river Brahmaputra. The losses are more in few places like (Majuli, the biggest river Island), Dhemaji, North Lakhimpur, Dhakuakhana and few places of Barak valley in Assam. The problem of flood is very old in Assam and the solution is very much difficult due to complex and devastating nature of the River Brahmaputra. Both short term and long term measures are sometimes failed to mitigate the losses caused by flood. This paper presents the case study on the losses in terms of livestock, human lives and that in terms of property that have taken place in Dhakuakhana area of Assam. Keywords: Water problem, flood, River, Brahmaputra, losses. 1. Introduction: India is a vast country with lot of diversity in water related problem with woes due to shortage and abundance in water. Western part of the country facing shortage of water and the Eastern part facing surplus of water in the form of flood. The Western part mainly comprises of Rajasthan, Delhi, Uttar Pradesh, Bihar shows shortage of drinking water and the eastern part shows abundant source of water. The North Eastern part of India mainly comprises of Assam, and its neighboring seven states are getting sufficient amount of rainfall in monsoon and hence the rivers become sufficient in water and causes flood in summer. Assam is one of the worst sufferers of flood due to River Brahmaputra and its tributaries and it comes in every year as a festival which causes woes rather than joy. The districts of Assam which are at the upper reaches of river Brahmaputra like Dibrugarh, Sivasagar, Jorhat, North Lakhimpur, Golaghat and the river Island Majuli are the worst sufferer of flood caused by mighty Brahmaputra. Here in this paper the folld havoc caused by river Brahmaputra in the place Dhakuakhana in the Districts of North Lakhimpur are discussed in terms of losses of livestock, paddy fields, human lives etc. The Fig.1 and Fig. 2 shows the physical and political map of the state of Assam wherin the district of North Lakhimpur is marked with arrow mark which is the district under discussion of this paper. Fig. 1: Physical Map of Assam Fig. 2: Political Map of Assam BALWOIS Ohrid, Republic of Macedonia - 25, 29 May

2 2. Brief Description of Dhakuakhana: Till the arrival of the Ahom from Thailand, under the leadership of SUKAFA in 13 th century AD Dhakuakhana was known as HABUNG. The legendary leader perhaps aimed at HABUNG. But he despised his plan when HABUNG got submerged during the devastating flood in 1244 AD and sailed to Dikhowmukh and was included by the Bhuyan s of Lakhimpur. It is however unknown, how long HABUNG was ruled by Bhuyan dynasty. The two major rivers/tributaries that run through HABUNG are CHARIKORIA and KORHA. CHARIKORIA said to have her name from the four KORIS (wins) that people had to pay to the boatmen to take them across. On the other hand during Ahom rule the royal tax collectors used to come by KORHA and had taken away goods forcefully from the tenants who failed to pay the taxes. Thus the river came to be known as KORHA which means takings away forcefully. The history of HABUNG is closely related with the Bhaktty movement started in Assame by Shankardeva. His great disciple Mahapurukh Madhabdeva passed his childhood IN Ghagaritool. During, Ahom rule Sanskrit was taught in TOOL S here. Today, Dhakuakhana is marching equal in respect of education and culture with the rest of the world. Looking in other material aspects of development the people of Dhakuakhana are but keen in this respect and consistently trying to make a global impact. Dhakuakhana is a place in the district of North Lakhimpur comprising large number of villages and some small growing towns. It is situated between north latitude and east longitude. It is situated between the mighty Brahmaputra and its tributary called Subansiri and basically of silt deposition mainly caused by these two rivers making it rich in fertility and hence ideally suitable for cultivation. During monsoon, many places of this area get inundated by the rivers and become inaccessible, when boat becomes the only means of communications. In Dhakuakhana, 94% population of this place is depend on Cultivation and can be taken as the backbone of the economy of the sub-division. About 3.5% is depend on Fish cultivation and 1.5 % population depends on livestock. So it can be concluded that the major economy of this region is dominated by cultivation of rice and other paddy crops and hence inundation of paddy field by flood water occurs during the period of cultivation brings tears to the people. The other impacts of flood as it always associated with erosion repeatedly displaced the person from one place to another which is the like killing of person admitted to the hospital. The sericulture sector of Dhakuakhana sub-division is also faced huge damaged due to recurring flood and sand deposition in the firm location. A survey conducted to access the migration pattern in the flood and erosion affected villages shows that more 60% of the youth from these villages have migrated to other places of the state and about 22% youth have migrated to other states of India. According to the June 2008 project Preparatory Technical Assistance, Phase-II draft feasibility report of the North East Integrated Flood and Riverbank Erosion Risk Management Project to be financed by the Asian Development Bank (ADB), the Matmora area of Dhakuakhana which has a dominant 58 percent schedule tribe (ST) population with a population density of 182 persons per square kilometer, is facing floods and erosion in a recurring manner for the past about a decade now, with 93 per cent of its 2,1186 households being affected. The area comprises 200 villages with per cent of its population being poor. It has so far incurred a loss worth around US $ million (around Rs. 90 crore) due to flood and erosion. The other factor affecting the livelihood of the people is sand deposition. 3. Causes of Flood: The construction of the embankment from Dijmur to Tekeliphutia on the right bank of river Brahmaputra was aimed at protection of the riverside villagers from annual devastating flood and subsequent intensive river bank erosion sixty years back. During the process more than ten thousand families were displaced from their paternal acre and till today many of these displaced families living on the embankment without having any compensation from the authority. The embankment could serve its purpose next thirty years of its construction but by this time the embankment caused permanent deterioration in the river character, the sand and silt load entrapped in between these two embankments -along right and left banks of the river lead to deposition of sediment in the river corridor which raised the river bed to an alarming extent and the earlier meandering character of the river changed into braided character. Thus the over-topping of flood water, frequent breach in the embankment, river bank erosion etc. become a regular phenomena for the river Brahmaputra. The flood due to river Brahmaputra as a result of these complications becomes more devastating and erratic in nature. The recurring flood, erosion, sand deposition, displacement these entire make several thousands of families marginalized and bulldozed the development efforts. The portion of the Dijmur-Tkeliphuta embankment form Sisikolghar to Matmora protects the riverine portion of Dhemaji BALWOIS Ohrid, Republic of Macedonia - 25, 29 May

3 district particularly the Pachim (West) Dhemaji, Machkhua portion and Dhakuakhana block of Lakhimpur district. The extensive bank erosion in this portion of the embankment actually compelled to realign the structure six to eight times in last twenty years. The erosion and realignment in construction of the embankment extinguished and eliminated about 18 villages from this area under Matmora and KherkotIa GP (Goan Pnachayat)s. In the year 2007 the embankment breached near Jhanji village and was about 500 mt wide, which was plugged in 2008 but there occurred three breaches in the same year which developed a wide opening in the embankment of around 2.5 km width. In the year 2009 efforts were made to construct the embankment using the geo-textile technology, which was continued till month of June This year the monsoon rainfall occurred in the North east only by last week of June, thus though the embankment construction work was started lately the works could continued till June. On 27th May 2009 a moderate flood occurred in 20 villages of this area due to influx of water through the opening in the embankment, which was explained by the water resources department as due to leach of water from a natural dam formed due to landslide blockade in the Tibetan part of Brahmaputra but as the rainfall was deficient by this time so the water was drained out by the small rivers. The effective rainfall started due to the monsoon rainfall started only by the 26th of June The following is the monsoon advance map of the country (Fig. 3). Fig. 3: Map for Advance of Southwest Monsoon (2009) The Brahmaputra embankment breached in 2007 near Janji village under Matmora GP was the starting of the recurrent flood in 2008 and in this year 2009, though efforts were made to plug the breached points but it could not served the purpose. The present flood is caused by the influx of water from river Brahmaputra through these points, the water carries heavy load of sediments which were deposited in many places, the roads and bridges connecting the villages were washed out or badly damaged due to flood water current, water logged in the low-lying areas up-to roof level till the sixth day of the flood. The public utility services were totally collapsed due to severe damage in the communication and high speed current. BALWOIS Ohrid, Republic of Macedonia - 25, 29 May

4 4. Consequences of the Flood of 2009: The details of consequence of flood on the population of the Dhakuakhana area in the District of Northlakhimpur are given in the table 1. From the data it is observed that large numbers of families are displaced from their original place of residence and the economic consequence is very large in terms of property and loss of crops. It is observed that children are the worst sufferer of the flood and hence it can be concluded that the future generation will be unable to do rather than saving their lives from flood. Due to displacement of the children from their location it will have very bad impact on their education, health as well as livelihood. The table from 2-5 elaborates the details of damages in entire state of Assam from in terms of crop area, population, loss of Human lives, Livestock and loss of dwelling units. The tables are self explanatory. Table 1: Details of affect on Population: Item Average ( ) Number of families affected 7476 Total population affected Male population (Approx) Female population (Approx) Children population (0-14 Yrs) (approx) Elderly person population 1320 (Above 60 Yrs) (approx) Number of Female headed 415 (Approx) Table 2: Flood Damages in India Item Average ( ) Maximum Area affected (in Million hectares) (1978) Population affected (in millions) (1978) Cropped Area affected (In Million Hectares) (1988) Damage to Houses (in millions) (1978) Number of Cattle Lost 96,713 6,18,248 (1979) Number of Human Lives lost ,316 (1977) Damage to houses, crops and public utilities (in Rs. Crores) (1988) Table 3: A summary of the flood damages in Assam ( ) ITEM TOTAL MAXIMUM Area affected (in Million hectares) (1988) Population affected (in millions) (1987) Damage to crops A) Area (In Million Hectares) B) Cost (in Rupees Crores) Damage to Houses A) In numbers B) Cost (in Rupees Crores) (1988) (1988) 33,27, ,99,835(1988) (1988) Number of Cattle Lost 4,31,537 1,08,913 (1987) Number of Human Lives lost (1988) Damage to public utilities (in Rupees Crores) (1988) Source: Revenue Department of Assam BALWOIS Ohrid, Republic of Macedonia - 25, 29 May

5 Table 4: Damages caused by flood in Assam ( ) Area affected (Lakh Hectares) Cropped area affected (Lakh Hect.) No of villages affected NA NA NA NA NA NA NA Population affected (in Lakhs) Human Lives lost (Nos.) No of cattle lost No of houses damaged No of houses eroded NA NA NA NA NA NA NA Value of crop damaged (in Rs. crores) Total loss (in Rs. crores) (Source: Girin Chetia: Magnitude of the problem of flood in Assam and its trend. In: PLAVAN, Vol IV, June, 1999.) Table 5: Damages caused by floods in Assam ( ) Area affected (Lakh Hectares) 2 Cropped area affected NA NA 1.18 NA NA (Lakh Hect.) 3 No of villages affected NA NA NA NA NA NA 4 Population affected (in Lakhs) 5 Human Lives lost Nil (Nos.) 6 No of cattle lost Nil No of houses damaged NA NA NA NA NA 8 No of houses eroded NA NA NA NA NA 9 Value of crop damaged NA NA NA (in crores) 10 Total loss (in crores) NA NA NA (Source: Directorate of Economics and Statistics; Assam) 5. Flood Control Measures: Flood control Department of the Government of Assam was continuously taking the effective measures to mitigate the consequence of devastating flood caused by river Brahmaputra and its tributaries. The river Brahmaputra is very critical to anlyse its flow and pattern of flowing in terms of its course. During monsoon its carries tremendous amount of silt with it eroded from its upper reach. As BALWOIS Ohrid, Republic of Macedonia - 25, 29 May

6 these silt has deposited in the plain area and hence it causes reduction in the channel capacity and hence erosion bank taken place. Very recently, a Malaysian company Emaskiara is executing the Matmora dyke at an estimated cost of around Rs. 140 crore for and Matmara protection project, at a cost of around Rs crore. The costruction will comprise of 1, 200 geo-tubes to build the dyke. But due to untimely flood between June 29 and July 2 and sunk 14 geo-tubes till July 2 in the area. Altogether, 146 geo-tubes were laid in the area to build the retirement dyke in a stretch of 5 km in which the original embankment was breached by the Brahmaputra last year. Explaining the development, Water Resources Department (WRD) sources said that of the 5 km stretch, the first line of the geo-tube was laid in a stretch of 3.5 km. Moreover, gaps were left at various places among the geotubes and the river side earth cover was also not provided to the already erected geo-tube structures. But, against the targeted progress of 90 per cent scheduled to be attained by this time, the company could attain only ten per cent progress in the work. 6. Conclusion: The construction of Matmora dyke with the use of modern and recent technology of Geo-Tube may help in preventing the erosion and failure of the dyke. All the people living in the flood affected area of Dhakuakhana and its adjoining area are eagerly waiting for its completion. An anomaly was observed in the time of construction of this dyke as it was constructed just before the monsoon and hence certain amount of Geo-tube has been washed away in last flood but we hope that the timely completion of dyke will bring joy and prosperity to the region. The cultivator of the Dhakuakhana will once again see their green paddy field and their life will be more comfortable in terms of health, wealth and education. References: 1. Central Water Commission (CWC), Government of India 2. Chetia, G. Magnitude of the problem of flood in Assam and its trend. In: PLAVAN, Vol IV, June, 1999India 3. District Disaster Management And Response Plan ( ), Dhemaji District, Assam 4. Goswami, S., Souvenir: National Workshop on Geodynamics of North-eastern India, Dibrugarh University, Dibrugarh, 1998, pp Goswami, Dulal, C., Flood Studies in India, Geol. Soc. India, Bangalore 1998, pp Indian Meteorological Department (IMD) ( 7. Lakhimpur District Website : 8. Rural Volunteers Centre Rapid Assessment Report 9. Situation Report Assam Floods, UNDP (03 July UNICEF Situation Report No. 2 Assam, Floods (2 July 2009) BALWOIS Ohrid, Republic of Macedonia - 25, 29 May