Vulnerability Comparision
6. Result and Discussion
6.1 Nature and Intensity of erosion: Main aim of our study is to find out the adaptation strategies of the people whose are living in the erosion prone area from many years. Before start discussion about this matter, we should have an idea about some basic characteristics of riverbank erosion as like as nature, intensity, or area collapse in the river of recent time.
Bank erosion is the wearing away of the banks of a stream or river. This is distinguished from erosion of the bed of the watercourse, which is referred to as scour. The two types of riverbank erosion are:
Undercut: Involves the removal of bank material by flowing water and carried sediment. Look for undercutting of the bank toe as a sign of scour and mass failure.
Mass Failure: Characterized by sections of the bank sliding or toppling into the stream. Look for bare and near-vertical banks as a sign of collapse.
In my study area there is mainly riverbank erosion characterized by undercut process, which carried out a huge amount of agricultural land, settlements, as well as other infrastructures.
Here mainly I calculate the total area collapse in river from the year 2010 to 2014 by using Google earth image. Mainly I draw line from north to south of my study area the measure the horizontal distance of nearby road from river of the vertical section in 1 km, 2 km, 3km, 4km, 5km, 6km and 6.20 km. I take this measurement of the year 2010, 2012 and 2014.
Figure 6.1- Google earth image 2010 Figure-6.2 Google earth image 2012
Figure 6.3- Google earth image 2014
Table 6.1: year wise distance of nearby road from river Source- Google Earth
2010 2012 2014
Horizontal Distance (road to Distance(road Distance(road Change in land Area(m)
section(southern) bank) in meter to bank) in to bank) in 2010-2012 2010-2014
meter meter
1km 195.18 222.01 295.85 26.83(+) 100.67(+)
2 km 652.21 627.46 413.19 24.74(-) 239.02(-)
3 km 963.95 766.30 506 197.35(-) 457.95(-)
4 km 686.15 574.88 960.03 111.27(-) 273.88(+)
5 km 661.50 460.46 659.55 201.04(-) 1.95(-)
6 km 1267.43 1029.21 752.55 238.22(-) 514.88(-)
6.20 km 1262.85 1041.15 706.20 221.7(-) 556.65(-)
High risk area (-) loss of land, (+) increase of land area
Medium risk area
Low risk area
From the above table we can see that year-by-year distance of road from the river is gradually declining in the most of the area. The most risky zone is 2 km, 3km, 6 km and 5.2 km. in these section the distance of road is gradually decrease year by year. In 2 km vertical section distance in 2010 was 652.21 m which decrease at 413.19 km in 2014 and it’s about 239.02m area collapsed in river during 2010-2014. As like as in 3 km, 6 km and 6.20 km the amount of land collapsed in river is about respectively 457.95 m, 514.88m and 556.65m during 2010-2014. So, these zones are characterized, as high risky zone as erosion rate of these vertical sections are higher than other area. In case of 1 km and 4 km, we can see that the horizontal distance of river from road is gradually increase from the year 2010 to 2014.
In the zones mainly due to deposition of sediment land area gained instead of land collapse.
The increase of land area is about 100.67 and 273.88(+) respectively in 1km and 4 km during 2010-2014. So these zones are characterized as low risky zone.
There is table given below which showing the river area and bank area in prospect of mainland area of the year 2010, 2012 and 2014 as well as total eroded area from 2010 to 2014.
Table 6.2: Comparison of Area (River area and Bank area) Source- Google Earth
Year River Area(sq. km) % with mainland Bank Area(sq. % with Eroded
area km) mainland area Area(2010-2014 in
sq. km)
2010 16.87 63.07% 9.88 36.94% .98
2012 17.51 65.46% 9.24 34.54%
2014 17.85 66.73% 8.9 33.27%
Form this table we can see that River area is increasing gradually whereas the bank area is declining day by day. In comparison with 2010 to 2014, the bank area decreased from 9.88 to 8.9 sq. km. whereas river area increased 16.87 to 17.85 sq. km. Total area eroded during 2010 - 2014 is about .98 sq. km. kazipur sadar union is a highly eroded area where it is about 1 sq. km.
area had gone under water in last 4 year. Erosion of land mainly toeards through west to eastern side. The river is widening day by day towards the eastern side. If it will continue there are many homesteads, agricultural land, roads, other important infrastructures like hospital, union parichad office etc. will go under water in very near future as well as kazipur sadar union will vanish from the map of Bangladesh. There is an erosion map of kazipur sadar union shown here.
Figure 6.4 - Erosion Map(2010-2014) Source-Author
6.1.1 Loss and damage Extent: An attempt has been made to understand the losses occurred due to riverbank erosion in the study area. In view of this, losses were accounted through the loss of agricultural land and production, loss of homesteads, loss of cattle etc.
Table 4.3- Eroded land in 2011 in comparison to 1973-2009 (year wise) Source- (BBS 2011)
Study Area Total Area (ha) Average Eroded Land Erosion in 2011 (ha) Percentage of total
(ha/year-1973-2009) land (%)
Kazipur sadar Union 2767.93 6.89 178.76 6.46
From the above table it showed that the amount of eroded land is increasing dramatically over 2009 to 2011 with the comparison of the average eroded area from 1973 to 2009 in Kazipur a union of sirajganj district while the average eroded area (1973-2009) of kazipur is 6.89 as it reached 178.76 and 203.36 in 2011. As we mention before riverbank erosion is a devastating hazard which cause a huge loss of life as well as valuable assets like crops, domestic animals etc. here we explain the loss and damage extent in two basic point which are-
Loss of agricultural land
Loss of households
6.1.1.1 Loss of agricultural land:There is table is given below which presenting the amount of land collapsed in river and their value for several responded.
Table 4.4: Total land collapsed and their value source: field survey (2014) Amount of land collapse in river in Value of land collapsed land (taka in Percentage of responded
last decade( in Bigha) lakh)
12 60 5
6 30 8
5 25 10
4 20 15
3 15 28
2 10 32
From the above figure, we can say that people have lost huge amount of land due to river bank erosion in my study area. For more clarification there is an explanation is given below with pie chart.
In given chart shows that maximum responded loosed about two bigha land due to erosion whereas only 5% people loosed about 12 bighas land as well as 8%, 10%, 15%, 29%
and 33% of responded losses respectively 6, 5, 4, 3, 2 bighas of land due to erosion in my study area. The value of land fluctuated between 60 to 10 lakh taka. From the above discussion there is a clear indication appear more clearly that, the people of river bank erosion prone area losses a huge amount of land every year. For this reason they have to fall in a miserable condition and there life also threaten. The
Figure 6.5: categorization of land lost (amount wise)
6.1.1.2 Loss of Homesteads: The level of economic loss and vulnerability of population due to bank erosion has dramatically increased in recent years. The impact of land loss reflects primarily through the loss of homestead land. An estimated 300,000 displaced persons usually take shelter on roads, embankments, and government-requisitioned lands.
It’s about 100% of responded told me that they have lost their households due to erosion.
6.1.2 Timing Of Erosion: River bank erosion mainly occur in after and before flood. It mentioned before that, in kazipur sadar union erosion mainly proceed through undercut process. It is because the soil characteristics of this area. Soil of this area is mainly sandy and have loose porosity. As a result water pushed in the lower portion thus lose sandy soil wash away through water and the segment of this site’s land become thin as collapse in the river. This is the mechanism of undercut process. Flood has a connection with riverbank erosion in case of timing. Mainly erosion in this area starts at two points.
1. When water over flooded through the riverbank.
2. At the time when floodwater go down after flood.
That mean usually in this area erosion starts at august and then September to November in this area.
6.2 Adaptation With Riverbank Erosion: Adaptation means coping with urgent behavior of nature. In broader sense when a disaster or any kind of unnatural/natural and unpredicted or predicted natural incident occurs behind us, adaptation implies that how we cope, adjust and survive with such sudden incident. In my present study I try to focus how the people of erosion prone area survive, manage and prepare themselves to continue their live with such as hazardous situation. In case of river bank erosion adaptation may be defined how the people of associated area coping with before and after of erosion. Here I define the adaptation in various contexts of riverbank erosion.
6.2.1 Agricultural Practise: As the part of adaptation the people of erosion prone area try to continue the agriculture practice far from river bank as much as they can or they try to preserve a certain amount for harvested crops as erosion can start at very sudden. Such kind of adaptation measure also depends on the ability of local people. During field survey, it observed that most of the agricultural land is just beside the river which are
severely vulnerable as any time can go under water. Everyone of this area know they should buy agricultural land far from the river. But the problem is their low income. For this reason They are not capable to do that. Very few people are capable to buy land far from the erosion prone are as they are economically solvent than other.
From the above chart it can be stated that most of the people of my study area are landless.
They lost their land in riverbank erosion due to river bank erosion of last decades. Only 10%
people of this area have own land for agricultural purposes and it’s about 85%
people of this area are landless as well as it is also observed that there is only 5% people have their own land outside of this area..
Landless people earn their livelihood by working as a day labor in other land or by land digging. This the overall land ownership condition of my study area.
Figure 6.6: Land ownership
From survey it observed that, about 60% cultivation occurred during winter season as it is the most secure time for cultivation. In the meantime, of winter season there is no provability occurring natural hazard like river erosion. On the other hand, there is about 40% cultivation occur during summer season where as there is no cultivation or farmers do not continue their agricultural activity during rainy as this is high time of occurring riverbank erosion. There is a table given below which shown the cultivable crops of my study area. There isatable is given below that show thee various crops that produced in my study area. Mainly in this area is basically a sandy as well as a huge amount of siltation occur every year due to flooding. Paddy is the most cultivated crops in this area. About 44% of total cultivation is paddy cultivation. Boro amon and the chinese is two main species of paddy cultivated here. On the other hand, during winter season various winter crops as like as wheat, corn, nut etc. are harvesting here. People of this area try to cultivate the harvests which can be cultivated at low cost as like as pulse, nut, various kinds of oil seeds, various kinds vegetables which can be produced in winter as these time there is no probability of occurrence river bank erosion. They try to avoid cultivate in rainy season as well as cultivate those crops which need high cost to cultivate. In this point of view agricultural practice is modified here to adapt with the riverbank erosion.
6.2.2 Household Patterns: People of the study area know that their household can be diminishing at any time as they have to relocate their household in very short time when erosion starts. For that reason, they build their households with such building materials that can be transferred within short period during erosion starts. According to the responded, they construct their households by tin because for the easy access of low quality old tin as well as their low price also. On the other hand straw is not available in this area. Another reason of using tin is the easy movability. Such kind of tin shade structures can be move easily than straw made homesteads.Such strategy for household construction makes them
many households go under water. In this case they become homeless as part of adaptation they move to another char or other area. As precaution measure they try to live at long distance from river.in my study area the distance of households from river is between 150 to 400 meters. About 35% of households are situated between 150-200m away from the river. These households are highly vulnerable to erosion whereas about 20% of households are situated between 250-300m and 300-400m and about 25% of households are situated between 200-250m. From the above explanation it can be said that most of the households of this area are in a vulnerable condition. Most of the responded know that it will better for them if they can move their household far from the river. But it depends on their ability.
Most of the people living in this area are poor and they lost their everything un the river bank erosion of last few decades. As a result, they have to live with such vulnerable condition.
6.2.3 Migration: Many people of erosion prone area are becoming homeless every year due to riverbank erosion. They have to shit another place to survive As mentioned before most of the people of study area are poor and they live under poverty line. Most of them shifted in the nearby dam behind the river and it is about 60% whereas about 30% and 10% have a tendency to shift in nearby road and in sirajganj sadar.
6.2.4Food security: It is about 35% of the villagers preserved rice for their future according to their ability as well as about 20% and 10% people preserve gradually wheat and dry food according to their ability whereas about 35% of people preserve no food item for the future as they are unable to buy or preserve food item for future with their low income. Mainly preservation of food items mainly depends on their ability. Basically, all of the villagers of this area are concern about the fact what will happen in near future when erosion will start but they have nothing to do as they have a very low income. Although people of this area take steps as much as they can to cope up with such extreme hazardous situation.
6.2.5 Preparedness: We know that riverbank erosion is a devastating natural hazard, which may occur at very sudden. Therefore, the people of the erosion prone should be prepared themselves for such hazardous situation. Most of the people of my study area have a clear concept about when erosion will take place. When erosion will start it’s about 90% people are concern about to move old and children as they are unable to move safely than the other member of the family. About 10% people are nit aware about that fact. It is about 95% people are capable of moving their household in safe place whereas about 5% people are not aware about that fact as they built their household with very low coast. At last about 95% of people are concern about the domestic animals of their own and they concern about to move them in safe place when erosion will start. In this case only 5% of them are not aware about this fact as they have domestic animals which are not easily movable like chickens, duck etc. This is the situation about the preparedness status in case of river erosion of my study area.
Occupation: About 70% people are day labor. Mainly day labors are working in the other’s agricultural land, soil digging etc. whereas about 20% are earning their livelihood by farming and fishing as most of them have their own land for cultivation in this category.
Only 10% people of this area are categories in other sector, which include garments worker whose are working in Dhaka, as they have nothing to do in their own area. Except this, many people go to nearby in district town such as in Sirajganj and Bogra for various working purpose like rickshaw pulling.
6.3 Learning’s for surviving with river erosion: Various leanings to survive with riverbank erosion is discussed below which may be helpful to decline the impact of riverbank erosion in erosion effected area of Bangladesh.
Nature and intensity of erosion: It is an important part about the learning and conceptual development about river bank erosion because if the people of erosion prone area have sufficient knowledge about the fact; they can easily estimate the impact as they will prepare for any remedial measurement thus the effect of erosion may be reduced on their livelihood.
Preparedness for urgent move: Erosion usually starts at a very sudden and within a short time it occurs a huge destruction. So the people of this area always should be prepared both physically and mentally for urgent move in safer place. They have to learn which properties are moveable and which are not. As they have to focus on such moveable assets which will helpful for their further settlement. They should be prepare themselves for the urgent move of their movable assets such as households, domestic animals, other important household materials etc.
Proper agricultural practice: We know that river bank erosion is an
unpredictable hazard which occur at a very sudden and collapse a huge amount land in the river when erosion starts which include cultivable as well as
cultivated land. So the people of the erosion effected people must be concern about this fact. They also have to learn about suitable agricultural practice because it will also be helpful for them for reducing the loss as agricultural land also collapse during erosion.
Proper household structure: We know that riverbank erosion is uncertain as well as unpredictable which carried away households in river water. To avoid such loss of homesteads people of effected area must have concern about this fact as for proper house hold pattern it is must necessary to learn about appropriate materials and patterns which will easier to move in safe place during erosion starts. Thus it will possible to reduce the loss burden of erosion.
Distance of households and agricultural land from river: The people of erosion prone area must pay attention on distance from riverbank in the case of household making or agricultural practice and build homesteads and harvesting far from the place towards which area erosion is occurring. If the distance between river and household or agricultural land is less then, possibility of collapse in river is more.
So the distance between river and agricultural should be more thus it will efficient for reducing the loss. It is necessary because it will minimize the risk of house hold or agricultural field collapse during erosion as much as possible.
Communication with local government and NGOS: Many NGOS are working for the development of effected and displaced population in erosion prone area.
Besides them local government is also conscious about them also. In my study area there are about three NGO whose area working for the erosion effected people. The name of the NGOS area Karitas, Shouhardo and Brac, Mainly karitas and shhouhardo works for the erosion effected people So the people of these areas should maintain a communication with these organizations as they can get help and other facilities or information about the river bank erosion. Thus, they can also reduce the loss burden of erosion.
Concern and consciousness about the children and old people: The risk of erosion varied through various age group whereas Children and old people are most vulnerable in this case. Because they are not capable like the other member of the family. So the people of this area must be concern about them. It should be planed and take necessary steps about how they moved from one place to another place during erosion. It will be possible then to move the old people and children in a safe place in a very short period.
Perfect place for domestic animals: At the mean time of after erosion domestic animals