Abstract:
The geographical location, lack of resources, huge rural population with fragile economic conditions and nature-based livelihood structure have made Bangladesh highly vulnerable to flooding and erosion. Majority of the flood victims belong to the Jamuna River floodplain and battle against frequent floods and riverbank erosion. Climate change exacerbates these challenges, particularly in low-income and natural resource-dependent communities. Although the victims are expected to be adaptable to normal flooding, severe flooding can force them into desperate survival measures. While local support systems aid in recovery, their effectiveness needs evaluation. Identifying key resilience parameters is essential for restoring and maintaining community resilience. But existing literature and official records are primarily concerned with large-scale tangible damages, and less so with household-level damages and tipping points. Adaptation Tipping Point (ATP) is essential for assessing resilience and adaptation capacity as well as risk acceptability at the local or community level of physical and social systems under present and predicted future scenarios. This study investigates the household-level ATPs in terms of flood-induced damages and recovery capacity of the flood and erosion victims. Three distinct areas, i.e., mainland (Chukaibari), attached char (Char Magurihat) and island char (Char Halka Habrabari) situated in Dewanganj upazila of Jamalpur district lying in the north-central region of the country are chosen. Later the mainland is divided into two areas as Badeshosaria and Rail-line slum due to the insights developed from the field works. The specific objectives of the study are: (a) to analyze flood and erosion hazards in the study areas, (b) estimate household-level ATPs due to flood and flood-induced damages, and (c) assess the households' bouncing back capacity in post-tipping conditions with existing local support systems. This study is based on a combination of quantitative and qualitative methods. Both primary and secondary data are collected and analyzed to achieve the objectives set for this study. The erosion-accretion analysis was conducted using the Landsat images in ArcGIS, covering changes over the past 27 years (1996-2022) along the Jamuna River. The trend of flood events was assessed through frequency analysis of water level data collected from 2004 to 2022 at the Bahadurabad Transit station. Additionally, NDWI analysis on the MODIS time series data was performed to evaluate the extent of flooding in the study area from 2004 to 2022. Reconnaissance and detailed surveys, FGDs, KIIs, and semi-structured questionnaires were conducted to determine the tipping conditions and values. ATPs were evaluated using appropriate equations, considering house damage ratio (HDR), in-yard damage ratio (YDR), income loss ratio (ILR), agriculture damage ratio (ADR), and overall aspects. A SWOT analysis of 14 local support systems was performed to assess the victims' bouncing back capacity. This qualitative understanding was constructed from primary data findings. The key focus areas were: local loan-providing systems, supplementary income from the household yard, mobility network, housing conditions, available utility services (electricity and water supply), health care facilities, knowledge and skill, access to information, land productivity, hazard parameters, seasonality and land-use change, participation in community activities, and social norms and practices.
The analysis of hazard parameters revealed an increase in the flood level and duration, while the extent of flooding has no abrupt changes after 2010 during the considered period. The study area experienced maximum accretion between 2011-2015 (1.62 km²/year) and maximum erosion between 2016-2020 (1.75 km²/year). Although no consistent pattern emerged over the past 27 years, significant changes were observed in the last 12 years (2011-2022) along the study area reach. The flood-damage tipping conditions varied across the three study areas, influenced by available resources and socio-economic norms. A household choosing the tipping condition for survival was considered as a tipped household. The final calculations indicated that the mainland had the highest (0.36) and lowest (0.19) tipping values, primarily due to difference in land ownership. Individual segments at HDR, YDR, ILR, and ADR showed maximum and minimum scores with differing patterns based on the local characteristics of the study areas. The nature of male-headed versus female-headed households and the size of household members also significantly influenced the tipping results. The detailed assessment of bouncing back support systems revealed that the major support systems for survival simultaneously were causing significant threats, leading to non-recovery, social conflicts, and widening power gaps within the study areas. Conversely, the systems which are undervalued for the recovery process, such as supplementary in-yard income, housing conditions and community participations, posed almost no threats and presented notably positive opportunities. The study was conducted in a historically flood-prone area, where residents have become adept at coping with the hazard. While structural and non-structural interventions have reduced the monetary value of flood-induced damages at a micro level, the impacts of changes in hazard parameters and the profit-driven motives of various stakeholders have hindered the victims' recovery.