https://orcid.org/0000-0001-8008-2496
Figures
Abstract
Climate-change-induced stress impacting water availability is a major threat to agriculture and livelihoods in low- and middle-income countries (LMIC), including Bangladesh. While technology-based adaptation measures can mitigate the effects of such stresses, and help to build community resilience, evidence-based research on this topic is scant. In consideration of this gap, using the southwestern coastal communities of Bangladesh as case study, the present study investigates empirically the dynamics of technology-based adaptations that affect the availability of water for drinking, domestic, and agricultural purposes. To this end, the efficacy of various technologies, adoption processes, accessibility, and societal resource distribution disparities is examined. Field-level primary data were collected in Kaliganj Upazila of Satkhira District—one of most vulnerable areas in Bangladesh—chiefly using three Participatory Rural Appraisal tools: a household survey (n = 300 households), Key Informant Interviews (n = 15) and Focus Group Discussions (n = 6). The findings of our investigation revealed that shallow tube wells (23.7%), deep tube wells (59.0%), rainwater harvesting (37.3%), pond sand filters (6.3%), reverse osmosis (37.3%), low-lifting pumps (38.0%), and deep submersible pumps (8.0%) were the technologies most often employed to address water-related needs; these measures significantly reduced climate-induced water stress. Significant variation in water source-dependency between two study Unions was found (P < 0.05). Community-based organizations, neighboring community members, and electronic media played a critical role in the diffusion of technology, mainly through their ability to raise awareness of these adaptation options, while affordability was identified as being vital to the ability to use technology to access water. This research underscores that advancing technology and deploying it in climate-vulnerable areas is not sufficient for achieving the desired outcomes of technology-based adaptations; also, it is necessary to ensure equitable access by various socioeconomic groups to water usage for attaining climate change adaptation goals in LMICs, like Bangladesh.
Citation: Haque CE, Shehab MK, Faisal IM (2025) Meeting climate change challenges in coastal Bangladesh: A study of technology-based adaptations in water use in Satkhira District. PLOS Clim 4(4): e0000460. https://doi.org/10.1371/journal.pclm.0000460
Editor: Zhipin Ai, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences, CHINA
Received: May 28, 2024; Accepted: April 1, 2025; Published: April 30, 2025
Copyright: © 2025 Haque et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the paper and Supporting Information files.
Funding: The research was funded by the Climate Change Program of the International Development Research Centre (IDRC), Ottawa, Canada (grant # 108960-002). The grant was provided to C.E.H. The funding agency had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
1. Introduction
Climate change has emerged as a pressing global issue and has received substantial attention from world leaders and policymakers. Developing countries are disproportionately affected by the uneven climatic variations and increased frequency of extreme weather events caused by climate change [1]. Like other low- and middle-income countries (LMICs), Bangladesh is contending with the effects of climate change, currently being ranked 7th in the long-term Climate Risk Index (CRI) [2]. In addition, Bangladesh has been ranked as the 3rd most vulnerable nation to global-warming-induced increases in sea-levels and the associated hazards [3]. At present, Bangladesh is home to 165.14 million people [4]. The Government of Bangladesh has designated 19 of its 64 districts as “coastal districts”, based on three specific criteria: tidal water movement, salinity intrusion, and cyclone risk. These districts are situated in the southern, southeastern, and southwestern regions of the country [5]. The coastal region is home to 43.81 million people, accounting for 26.53% of the nation’s total population [4]. Notably, it is also home to a vast rural population that predominantly relies on an agrarian economy to sustain its livelihood [6]. Heightened exposure to changing rainfall patterns, floods, cyclones, tidal surges, droughts, waterlogging, rising sea levels, and salinity intrusion has adversely impacted the lives and livelihoods of Bangladesh’s population, both directly and indirectly [3,7]. Unfortunately, the occurrence of severe climate events is increasing at a rapid pace. Indeed, Bangladesh experienced 113 climatic disasters between 1991 and 2016 compared to only 58 between 1965 and 1990, an increase of nearly 100% [6]. Furthermore, it is estimated that climate change has resulted in economic losses of US$12 billion in Bangladesh over the past four decades [8].
Among natural resources, water is the primary medium through which the impacts of climate change are manifested [9]. Due to its location, Bangladesh’s coastal area is more exposed to climate-induced geophysical and hydro-meteorological hazards, which can have devastating impacts on water resources [10]. Drastic changes in precipitation patterns in these coastal areas, particularly heavy precipitation during the monsoon period, can create massive runoffs, which in turn result in flooding, river erosion, and waterlogging [3,11]. Additionally, considerably low levels of precipitation during the lean period (non-monsoon) pose a threat to freshwater ecosystems and water quality, further exacerbating vulnerabilities in the region [10,12]. Furthermore, the average temperature in Bangladesh’s coastal region is increasing at a rate of 0.023°C per year compared to 0.009°C in its inland areas [7]. The rising temperatures in the coastal region have negatively impacted the freshwater ecosystem and threatened the safety of the area’s drinking water, as they have resulted in higher pHs and waterborne pathogens, and decreased levels of dissolved oxygen in the water supply [7,13]. Extreme salinity intrusion is another effect of climate change that significantly threatens social stability in Bangladesh’s coastal region. In recent years, increased salinity intrusion into water bodies has resulted into several undesirable features, including higher land surface temperatures and, by extension, higher evaporation rates and more erratic rainfall patterns [10,14,15]; increased frequency of tropical cyclones and storm surges [16]; and rapid increases in coastal sea levels [17].
Rising sea levels drive the long-term lateral intrusion of saline water from the Bay of Bengal into the coastal region’s fresh groundwater aquifers and, consequently, their shrinkage and contamination [17,18]. Khanom [19] found that, between 2000 and 2009, salinity intrusion increased to up to 15 km from the south coast during the monsoon season and up to 160 km during the dry season. This situation has been further exacerbated by the uncontrolled withdrawal of groundwater and the inhabitants’ increased dependency on it, as this demand has resulted in the depletion of the fresh groundwater table and contributed to increased salinity intrusion [20,21]. Such climate-induced phenomena have significantly damaged water ecosystem services in Bangladesh’s coastal region, causing severe crises regarding the availability of freshwater for drinking and irrigation. In addition to climatic features, studies have revealed that the Ganges river flow has been controlled by the Farakka barrage in India. This control has significantly reduced the maximum, average, and minimum discharges by 23%, 43%, and 65% respectively during the dry season (January to May) when comparing the pre-Farakka period (1935–1975) to the post-Ganges water sharing treaty period (1997–2015). This reduction has further contributed to increased salinity in downstream water bodies, deteriorated water quality, and accelerated the water crisis in Bangladesh’s southwest coastal region [22,23].
Technology-based adaptations in the water sector can contribute to substantial improvements in quality of life, as they can build resilience to extreme climate hazards, reduce drinking water contamination, and promote the diversification and conservation of water resources. The long-term application of environmentally-sound technology is a highly recommended adaptive measure for alleviating climate-induced stress on water resources [24]. Some of the major adaptation technologies implemented globally in recent decades include rainwater harvesting, water storage, water reuse, desalination, increasing irrigation efficiency, and effective water use. The literature on climate change adaptation in coastal Bangladesh reveals that rainwater harvesting, pond sand filters, and tube wells are the most common hard technologies employed to mitigate climate-induced stresses and address drinking water scarcity [25,26]. However, inequalities in access to technology and disparities in resource distribution remain major concerns, as these social justice dimensions can impede the adaptation process. Moreover, the scarcity of information relating to the dynamics driving different socioeconomic groups’ adoption of such technologies limits the ability of policy-making institutions to deploy effective technology for reducing climate-induced water stress.
An extensive search for empirical research underscores a critical knowledge gap in the southwestern coastal region of Bangladesh, particularly concerning the impacts of climate change on water resources, and their associated adaptation processes. The local adoption of technological solutions to alleviate stress in drinking water, domestic use, and agricultural sectors remains largely unexplored. In addition, the dissemination of knowledge and information regarding these technology-based adaptations within the local context requires further scholarly attention. In terms of the key scientific research question, this research addresses what technology-based adaptation measures are being adopted in alleviating water scarcity; and what are the processes and underlying factors involved in expanding these adaptive approaches in southwestern coastal communities. This work makes a novel contribution to the literature concerning the nature and extent of adoption of technology in water related adaptation in the southwestern coastal areas of Bangladesh.
This study attempts to answer the following specific research questions:
- What are the noticeable impacts of climatic variabilities on water resources, as experienced by the coastal inhabitants?
- What are the specific technology-based adaptations being considered and adopted in livelihood-related water sectors?
- What factors (e.g., communication channels, social structural dynamics) influence the adoption process concerning technology-based adaptations in water and agricultural sectors?
2. Conceptual considerations
The diffusion of innovation has been widely researched in various fields, including education, sociology, healthcare, renewable energy, and climate change. Rogers et al. [27] define diffusion refers to the process by which novel concepts, technology, or procedures are disseminated over time among individuals within a social system through various communication routes. The theory offers a compelling organizational framework for integrating the influence of both core and supplementary factors that drive the diverse adoption behaviors observed among households [28]. In this study, Rogers’s [29] Diffusion of Innovation theory was applied to elucidate the key driving factors of adoption and implementation of adaptation approaches in the water resource management sector in Bangladesh’s southwestern coastal regions. The conceptual framework of this study was purposefully designed to focus on three of the four core elements of Rogers’s theory, specifically to address the existing research gap and align with our research objectives: 1) technology, 2) communication channels, and 3) the social system (see also Sahin [30]). In addition to examining the dynamics driving the adoption of technology as an adaptation measure in Bangladesh’s water sector, this work also considers the findings of the FAO study regarding climate change’s impact on aquaculture and adaptation management [31]. Fig 1 illustrates the primary dimensions used to evaluate the three elements of Rogers’s theory vis-à-vis the adoption of technology as a climate change adaptation, as well as the consequences of adopting technology-based adaptation based on different scenarios.
Note: Climatic adaptation measures in the water sector are rated according to the capacity required for implementation and are marked as low (L), moderate (M), or high (H).
The term, “technology,” is a broad concept. However, in this paper it will be used to refer to “a form of human cultural activity that applies the principles of science and mechanics to solve problems. It comprises resources, tools, processes, personnel, and systems developed to perform tasks and create immediate, personal, and/or competitive advantages in a given ecological, economic, and social context” [32, p.138]. Other scholars define technology as instrumental action perceived as a new object that reduces ambiguity in cause-effect interactions to achieve a desired objective [29,30]. Following the 2005 United Nations Framework Convention on Climate Change (UNFCCC), the application of technology-based adaptations to reduce the effects of climate change began to receive significant global attention. The UNFCCC defines technology-based adaptations as the practical application of skills and scientific knowledge via environmentally friendly mechanisms with the aim of building resilience of natural ecosystems or human society to the impacts of climate change [33,34]. The study assesses the application of hard technology—defined as, “manufactured goods or equipment” [35], p.165)—as an adaptation to climate change in three major water-consumption areas: drinking, domestic, and agricultural.
Communication and diffusion channels are the mechanisms through which information and knowledge generated by individuals or institutions are spread throughout a community [29,30]. The development and diffusion of scientific-knowledge-based adaptation measures is strongly correlated with communication facilities wherein different actors and institutions play a major role as a mediator [36,37]. A wide variety of factors influencing communication and diffusion channels have been identified in the literature, including: stakeholders’ involvement in the community [38], role of gender [39]; contributions from government organizations (GOs) [40] and non-government organizations (NGOs) [41]; the diffusion of information through electronic media [42]; and private sector engagement [43]. These factors significantly influence adaptation measures, for example, in the form of supportive policies and regulations, capacity building, and public-private partnerships. For example, in northern Japan, a small group of farmers initiated peach cultivation alongside apples, acknowledging that peaches are more suitable for warmer climatic circumstances to capture a niche market. Initially, the diffusion process was decentralized, driven by the farmers’ independent initiatives. However, it eventually became centralized when local governments and agricultural cooperatives intervened, providing technical and financial support and promoting crop diversification as a strategy to adapt to the warming climate [44].
The social system consists of a group of connected entities engaged in collective problem-solving to achieve a shared goal [29,30]. In other words, social system comprises important actors and their interactions, including governmental bodies, corporations, people, groups from civil society, and academic institutions, playing crucial roles in gathering information, making decisions, determining the allocation, and distribution of resources [45]. The social system plays a crucial role in ensuring the equitable distribution of resources within a community, which in turn helps to strengthen the community’s adaptive capacity [46]. In this work, adaptive capacity will refer to “the minimum resourcing requirements to successfully implement the adaptation measure and includes human resources, financial resources, technical capacity, and/or the need for supporting institutions or entities” [31, p.38]. Apart from financial considerations (i.e., affordability), many studies have identified the equitable distribution of resources and facilities within a society as being a major factor influencing the adoption of appropriate adaptation measures [31,47,48]. For instance, in 2003, the forest landscape restoration project was introduced in Madagascar with the objective of introducing advanced technological approaches within local communities, enhancing education and knowledge levels, and fostering sustainable reliance on forest resources to ensure ecological stability. The project’s success was significantly bolstered by the inclusion of local authorities and community leaders in the governance structure, which facilitated effective resource allocation and the achievement of the project’s goals [49]. Disparities in resource distribution across socio-economic groups not only limit adaptive capacity, but it can also result in disproportionate hardship for marginalized people, thus further exacerbating pre-existing social inequalities [47,50]. For example, in Namibia’s decentralization of rural water management, authority was shifted to community-elected water point committees by 2007. However, poor transparency and accountability allowed local elites to dominate, securing disproportionate access to water resources. Marginalized groups were often left disadvantaged, compelled to labor for elites to access water when unable to meet the committees’ payment demands [48].
3. Materials and methods
3.1. Ethics statement
The research and data collection protocol were approved by the Joint Faculty Research Ethics Board at the University of Manitoba, Canada [Protocol Numbers: J2019:068 (HS 23008 and HE2022–0207)]. Data for the study were collected with written consent of all participants, by following the University of Manitoba, Canada’s ethics protocol. The procedures used in this study adhere to the tenets of the Declaration of Helsinki. Information about the scope and objectives of the study was provided prior to data collection, written consent was collected, respondents were informed of their right to withdraw at any time, a debrief with respondents was conducted about the preliminary results of the research.
3.2. Study area
The coastal region of Bangladesh faces heightened vulnerability to climate-induced hazards, including floods, cyclones, tidal surges, droughts, waterlogging, and salinity intrusion, particularly when compared to inland areas [10]. The country’s geographic location positions it as the third most vulnerable region globally to the escalating risks associated with rising sea levels [3]. Satkhira is regarded as the most vulnerable of Bangladesh’s 19 coastal districts, as it is highly vulnerable to risks such as cyclones, rising sea-level, waterlogging, and saline intrusion [18,51]. In addition to these challenges, key economic activities in Satkhira, such as agriculture, shrimp farming, tourism, and forest resource collection, are severely impacted [52]. The increasing frequency and intensity of climate-induced hazards have significantly disrupted local livelihoods and exacerbated freshwater availability, leading to severe water scarcity for drinking and irrigation [18,53]. Despite the implementation of several adaptation measures in alignment with the Bangladesh Climate Change Strategy and Action Plan 2009, critical gaps remain in the literature regarding the effectiveness of various technologies, local adoption processes, equitable access to affordable and safe water services, and disparities in resource distribution. To address these gaps and inform future policy development, this study was conducted in two Upazilas (sub-districts) within the Satkhira district, offering novel insights into local adaptation strategies and technology efficacy.
Kaliganj Upazila (sub-district) was selected as the study area for this research, as its vulnerability index of 0.66 was significantly higher compared to other Upazilas in the Satkhira District [54]. In terms of geography, Kaliganj Upazila is located between 22°19’ and 22°33’ (north latitudes) and 88°58’ and 89°10’ (east longitudes) and has a total area of 333.78 sq km [55] (Fig 2). The study was conducted in the Krishnanagar and Mathureshpur Unions, which were selected at random from the 12 Unions within the Satkhira district. The Krishnanagar and Mathureshpur Unions encompass total areas of 26.65 sq km and 37.79 sq km, respectively [55].
Data layer source: HDX 2022. Note: The names of the studied villages are marked on each Union map.
3.3. Data collection procedure
Considering the objective of our study, a participatory research approach was employed. Participatory research emphasizes the use of a “bottom-up” technique, which involves privileging perspectives and priorities within a given local context [56]. Data was collected using a mixed-methods approach comprised of two participatory research appraisal (PRA) tools (i.e., key informant interviews and focus group discussions) and a household survey. The selected approach facilitated a well-rounded understanding of the research questions and responses and allowed for the triangulation of the findings, thus enhancing the reliability and validity of the results [57]. The household surveys, Key Informant Interviews (KII), and Focus Group Discussion (FGD) sessions were conducted in either Bengali or English (depending on the respondents’ preferred language) in accordance with the established protocols regarding consent. The respondents were recruited on 15 November 2022 and their participation continued until 22 July 2023.
3.3.1. Household survey.
The household survey is a pragmatic and extensively used quantitative method for assessing technology-based adaptive measures in response to climate change within the water sector [58,59]. In the present study, a sample of 300 households from the Krishnanagar (n = 144) and Mathureshpur Unions (n = 156) was selected using a random sampling method. A total of 5 villages from each Union were chosen randomly (Fig 2), with the heads of the selected households being invited to participate in the survey. The survey was a structured questionnaire (S1 Data) consisting of questions relating to socioeconomic attributes, water supply sources, the impact of climatic variability on water sources, the types and effectiveness of technologies adopted as adaptation measures, assess-to-technologies, and disparities. On average, the survey took approximately 30 minutes to complete.
Rahman et al. [60] used annual household income to create a socioeconomic profile of Bangladesh’s coastal communities. Conversely, a few researchers have defined the socioeconomic profiles of LMICs using “per day per capita income,” with reference to poverty line values provided by the World Bank [59,61–63]. In this study, we used per day per capita income data from the household survey to divide the participants into three socioeconomic groups: very low- and low-income (less than or equal to US$1.90 per day); lower middle-income (less than or equal to US$3.20 per day); and upper middle-income (less than or equal to US$5.50 per day).
3.3.2. Key informant interviews (KIIs).
To attain a nuanced understanding of the research questions, a total of 15 key informant interviews (KIIs) were conducted with individuals possessing direct and relevant experience and expertise. The KIIs were conducted up to data saturation to ensure a comprehensive analysis of climate-induced stress, technology-based adaptations, and the dynamics of technology adoption in the water sector. The interviews utilized a combination of open-ended and semi-structured questions to elicit detailed and in-depth data regarding the participants’ views, experiences, and understandings of the research subject. Participants were purposively selected from the study area and included 3 crop farmers, 2 shrimp cultivators, 1 day laborer, 1 schoolteacher, 2 local leaders, 2 NGO practitioners, and 4 members actively engaged in the governing bodies at Union and Upazila levels. Five KIIs were conducted in Krishnanagar Union, 7 were conducted in Mathureshpur Union, and 3 in Kaliganj Upazila. Notably, only 2 women participated in the KIIs due a lack of knowledgeable and literate women in the study communities. Each KIIs took an average of 45 min to complete.
3.3.3. Focus group discussions (FGDs).
Focus group discussions (FGDs) provide participants with a platform to share their views and experiences, which yields a comprehensive understanding of their reality with respect to a given research topic. We conducted a total 6 FGDs (3 in each Union), with potential participants being identified through snowball sampling [64]. From this sample, we randomly selected 12–16 participants for each FGD. A total of 80 participants in 6 FGDs came from diverse occupational backgrounds and included farmers, shrimp cultivators, small landowners, teachers, local government officials, community-based organization representatives, and elderly individuals (Table 1). In total, 14 women participated in the FGDs. The FGDs were conducted using a semi-structured questionnaire that addressed disparities in adopting technology as an adaptation approach to reduce water stress; the roles of stakeholders in adopting technology; and constraints and barriers to expanding technology-based adaptation. Each FGD lasted for approximately 60 minutes.
4. Results
4.1. Impact of climatic variabilities on water resources
Krishnanagar Union is situated near the banks of the Galghasia River, while Mathureshpur Union lies along the Kakshiyali River [55]. Both Unions are interspersed with numerous tributaries, distributaries, and small water bodies, such as ponds. The key socioeconomic attributes of the households surveyed in Krishnanagar and Mathureshpur Unions are presented in S1 Table. Notably, statistical analysis using regression analysis or significance testing could not be applied in the context of the present study. In the present study, first, the dataset is relatively small, consisting of only 300 households from two Unions, with only 8 households (less than 5%) classified as “wealthy.” Consequently, significance tests, such as the chi-square test, are not suitable for assessing whether socioeconomic status (e.g., wealthy or poor) influences response variables, like the adoption of technology for drinking, municipal, and irrigational water supply. Second, the collected data were primarily categorical or grouped, and the small observed frequencies in some categories prevented the likelihood function from converging for accurate regression parameter estimation. This limitation precluded the appropriate application of regression analysis to determine the influence of various factors on the adoption of technological adaptations.
Agriculture was identified as the predominant source of livelihood for the majority of households in Krishnanagar Union, followed by wage labor and various other professional pursuits, while aquaculture (e.g., collecting shrimp fry, shrimp, and other fish farming) was cited as the primary source of income for most households in Mathureshpur Union (Table 1). A comparative statistical analysis (P < 0.05) has revealed significant differences in water source dependency between Krishnanagar and Mathureshpur Unions for drinking, domestic, and irrigation purposes (Table 2). Despite the proximity to these surface water sources, residents of Krishnanagar Union predominantly rely on groundwater, while Mathureshpur Union exhibits greater use of surface water and rainwater for meeting these needs.
Local stakeholders from both Unions identified climate change-related hazards, including changing rainfall patterns (e.g., inadequate and extensive rainfall), increasing temperatures, waterlogging, and salinity intrusion has created a water crisis in relation to both drinking and agriculture uses (Table 3). In addition, consistent with existing literature, they expressed significant concern regarding the substantial reduction in upstream river flow, which exacerbates salinity intrusion in surface water sources [22,23]. Household survey data obtained using a Likert scale captured the negative impacts on water sources, their availability, and water quality caused by uneven climatic variability and extreme climatic events (Fig 3). Notably, the majority of respondents reported that climate variability in the region had extensively affected the availability and quality of surface water (78.47% in Krishnanagar Union and 68.59% in Mathureshpur Union; n = 300) and groundwater (54.86% in Krishnanagar Union and 75% in Mathureshpur Union).
Source: Collected field data 2022.
The respondents of the household survey also reported that salinity intrusion had significantly impacted the quality of surface water and groundwater sources (75% in Krishnanagar Union and 82.69% in Mathureshpur Union; n = 300), resulting in unbearable suffering for people living near the coastal belt along the riverbank. Additionally, in the KIIs (n = 15) and FGD sessions (n = 80), the local farmers noted that salinity levels typically increase from December to July, reaching excessive levels between March and May. Apart from the regulation of river water flow by the upstream country, the major climatic factors influencing salinity intrusion in the study area were inadequate rainfall, high temperatures, and rising sea levels. Furthermore, the participants of KIIs and FGDs observed that the expansion of shrimp farming into low-laying and arable lands in both study Unions had also contributed to increased salinity intrusion. The expansion of shrimp farming into these areas entails the redirection of saline water from coastal rivers to inland locations via sluice gates, which are predominantly controlled by large shrimp cultivators and local elites. Finally, the KII and FGD respondents identified water seepage from coastal rivers due to weak embankments and water overtopping from increased tidal-water levels as frequently occurring events that significantly influence salinity intrusion.
These stressors had an especially severe impact on drinking water availability, as over half of the FGD respondents in both Unions reported that climate-based stressors had significantly restricted their access to potable water [55.56% in Krishnanagar Union (n = 40) and 70.51% in Mathureshpur Union (n = 40)]. Similarly, the majority of FGD respondents in Krishnanagar Union (70.83%) and Mathureshpur Union (57.05%) reported that climate-based stressors had negatively affected the quality of the drinkable water they were able to access. The participants further shared that drinking water scarcity reached extreme levels during the dry season, as the lack of precipitation resulted in lower groundwater levels and higher salinity.
More than half of the FGD respondents from Krishnanagar Union (58.33%) and Mathureshpur Union (60.90%) reported that climate-based stressors had moderately impacted the availability of water for irrigation. This finding is notable, as the livelihoods of local people, especially in the agricultural sector, depend on the availability and quality of irrigation water. Lack of access to fresh water, extreme salinity intrusion into the groundwater, and insufficient rainfall often force farmers to use saline water, which results in reduced productivity and high economic losses.
4.2. Adoption of technology as an adaptation process in the coastal water sector
According to the Union Parishad authority, there are approximately 2,050 privately-owned tube wells, 377 low-lifting pumps, 1 community-based rainwater harvesting system, and 10 pond sand filters in the Krishnanagar Union. Conversely, Mathureshpur Union has around 1,052 privately-owned tube wells, 4 community-based rainwater harvesting systems, 16 pond sand filters, and 2 privately-owned deep submersible pumps. Table 4 shows the distribution of technologies used to obtain drinking, domestic, and agricultural water by socioeconomic group. As can be seen, most respondents in Krishnanagar Union depended on deep tube wells (DTW) for their drinking and domestic water supply, while reverse osmosis (RO) and rainwater harvesting (RWH) were more commonly used in Mathureshpur Union. Furthermore, the household survey respondents from both Unions expressed a general preference for low-lifting pumps (LLP) as the best technology for ensuring an adequate supply of irrigation water (Table 4).
A Likert scale was employed to assess these technologies’ effectiveness as adaptation strategies for alleviating climate-induced water stress (Fig 4). The data revealed that, in both Unions, groundwater-based technologies (e.g., RO, DTW, and deep submersible pumps (DSP)) were viewed as highly efficient adaptation techniques for dealing with climate-induced water scarcity, while shallow tube wells (STW) and pond sand filters (PSF) were viewed as less efficient, and, thus, were less favored.
Source: Collected field data 2022.
4.2.1. Tube wells.
Tube wells consist of a thin tube that is driven into the sub-surface to extract the groundwater from a confined aquifer. Tube wells were introduced to Bangladesh during British colonization in the 1920s and were subsequently adopted, with support from governmental and international organizations, in the 1960s and early 1970s as part of the Green Revolution initiatives. By the early 1990s, approximately 95% of rural communities in the country depended on tube wells for their drinking water supply [65]. Households that rely on STWs typically utilize the water for domestic purposes. However, in 1993, arsenic contamination was detected in tube-well water [66], which led to a significant decline in the use of hand-driven STWs for drinking water (the Department of Public Health Engineering (DPHE) defines STWs as wells with a boring depth of less than 76.2 m [67] (Table 4). The perceived ineffectiveness of this technology can be seen in Fig 4. Indeed, the rising health risks associated with the use of STWs have become a major public concern and have highlighted the urgent need for alternative sources of clean drinking water.
During the early 2000s, both the government and international institutions ardently promoted the adoption of DTWs (which have a boring depth greater than 76.2 m [67] as reliable and effective substitutes for STWs. By 2015, DTWs had surpassed STWs as the principal source of drinking water for 75% of the population living along Bangladesh’s southwest coast [68]. The principal advantage of a DTW is its capacity to provide safe drinking water without additional treatment or electricity [69]. This ability makes DTWs a highly effective option for addressing the climate-change-induced freshwater scarcity and has led to its widespread adoption (Fig 4) in both Krishnanagar and Mathureshpur Unions (Table 4). Households that had installed a DTW used the water for both drinking and domestic purposes. The KII and FGD participants cited the lack of an available high-grade aquifer and a shrinking groundwater table as the two major barriers to installing a DTW; this was particularly the case in Mathureshpur Union, where groundwater had been highly affected by salinity intrusion caused by rising sea levels and man-made factors.
4.2.2. Rainwater harvesting (RWH).
Rainwater harvesting (RWH) is an ancient, time-honored technique that involves careful collection, preservation, and purification of rainwater for daily use [70]. While the roots of RWH stretch back to Prehistoric times (3,200–1,100 BC), its current global popularity has been fostered by technological advancements such as the incorporation of roof catchments and water filtration facilities into RWH systems [70–72]. The relatively lower installation costs for RWH systems have made them an effective adaptation approach for the LMICs, where per capita water consumption is significantly lower compared to more developed countries [73]. RWH is an especially promising and sustainable water supply option for Bangladesh’s coastal regions, as these areas are increasingly experiencing critical water shortages during the dry (i.e., non-monsoon) season due to erratic rainfall patterns caused by climate change. The household survey (n = 300) results indicated that approximately 45% of the population in the study area had access to RWH for their water needs. Depending on the size of the reservoir, a typical RWH system can fulfill the water needs of a four-person family for four to six months.
The use of RWH for drinking purposes was significantly limited, especially in the Krishnanagar Union, primarily due to potential health risks posed by contamination from bird excreta, plants, dust on the rooftop, and design flaws that do not permit the first foul rainwater to be bypassed in order to maintain microbial quality [74]. In recent years, the emergence of other reliable technologies has reduced dependency on RWH for drinking water purposes in recent years (Fig 5); however, the household survey data showed that most people in the Mathureshpur Union (where DTWs are rarely found) still relied on this method to meet their drinking water requirements (Table 4). Although RWH was rated as average in terms of effectiveness due to its maintenance requirements and limited usefulness during the dry season (Fig 4), stakeholders from both Unions nevertheless recommended it as a climate change adaptation technology, as it can be highly efficacious for meeting drinking, domestic, gardening, and homestead water demands during water-stressed periods.
4.2.3. Pond sand filter (PSF).
Bangladesh’s rural population relies heavily on ponds as a primary source of water for their daily needs. Unfortunately, pond water is often contaminated with high levels of turbidity and bacteria, which can lead to significant health complications, including diarrhea, dysentery, and cholera. In response, the implementation of a low-cost PSF is a popular water treatment option in rural areas of Bangladesh. PSFs are small-scale filtration devices made of brick chips, stones, sand, and plastic pipes that are installed at the edge of a pond and manually operated by a hand-driven tube well [75,76]. This technology was introduced to Bangladesh’s coastal regions in 1984 by the DPHE and the United Nations Children’s Emergency Fund (UNICEF) to ensure the region’s access to a safe water supply [75]. On average a PSF costs around US$1,500 to install [10], with a standard-sized PSF (8 meters in length, 2.7 meters wide and 1.8 meters tall) having the capacity to treat up to 1,000 liters per hour. This volume of production is capable of satisfying the water needs of around 100 households [76].
Despite these advantages, the household survey results revealed that residents in the Krishnanagar and Mathureshpur Unions generally relied on technologies other than PSF to meet their drinking, domestic, and irrigation water needs (Table 4). The household survey participants viewed PSFs as being ineffective, instead preferring the use of more advanced options to attain a safe water supply (Fig 4). Furthermore, the KII and FGD respondents noted that high rates of infiltration and evaporation often led to ponds drying up, thus rendering PSFs unusable. As highlighted by the KII participants, another obstacle to the use of this technology is the challenge of finding ponds that are not used for fish farming, bathing, washing clothing, and watering livestock. This challenge is even more pronounced in regions where water scarcity has become a crisis due to climate change. Additionally, PSFs are not suitable in areas with extremely high saline, potassium, and chloride levels. Despite their effectiveness in reducing coliform and general bacteria levels, PSFs are unable to eliminate pathogens from contaminated water, which may pose health concerns and decrease their appeal in the study area.
4.2.4. Reverse osmosis (RO).
RO is a membrane-based desalination technology that was invented in 1964 by Srinivasa Sourirajan [77]. In this technique, water is purified by using pressure to separate out sodium chloride, dissolved solids, and other impurities [77–79]. RO has become widely used for water purification applications throughout the world, as its effectiveness is comparable or superior to other desalination and water treatment methods [80]. Over the last decade, many non-governmental organizations and private sector enterprises have invested in this technology via a locally owned fee-based business model in an effort to promote the construction of RO facilities along the coast of Bangladesh [81,82] (Fig 5). These projects have demonstrated RO’s ability to successfully alleviate the lack of potable water, which has motivated the steady growth of this technology’s popularity within Bangladesh’s coastal communities. As part of this initiative, wealthy residents in the study region have been encouraged to become “water entrepreneurs” by funding the construction of groundwater-based RO plants.
Among the various technologies, the household survey participants from the Krishnanagar and Mathureshpur Unions rated RO as the most effective for dealing with climate-induced stresses on drinking water availability (Fig 4), with a total of 72.91% of households (n = 300) depending on RO plants to meet their drinking water demands. The cost to install an RO plant capable of producing 1000 liters per hour is approximately US$26,000, which includes all machinery and civil structure costs [82]. The KII participants elicited that drinking water produced by an RO plant costs US$0.005 per liter if it is picked up from the plant, and US$0.01 per liter if it is delivered. Both KII and FGD respondents noted that RO’s efficacy in providing safe drinking water and improving quality of life by reducing water-borne diseases has led to its exponential adoption in many other parts of the world. Furthermore, RO plants provide employment opportunities for local individuals, particularly women, who often oversee their operation and maintenance. However, this technology is hampered by a number of limitations, including high energy consumption, the need for frequent chemical cleaning, and the need to replace membranes and other machinery to avoid membrane fouling and to obtain the optimum output [Jiang et al. 2017]. In an effort to minimize membrane fouling and prolong the lifetime of the RO systems, most of the RO plants in the study region were strategically located in areas with lower salinity levels. As a result, the RO plants operated primarily using high-quality groundwater, thus bolstering the cost-effectiveness of the technology.
4.2.5. Low-lifting and deep submersible pumps.
Water lifting devices have been employed to provide water since as early as 3,000 B.C. [83]. The demand for and applications of water lifting methods in various industries has significantly increased alongside advances in these technologies. Until the 1970s, the people of Bangladesh relied entirely on canal water and rainfall to satisfy their agricultural water demand [84,85]. However, this practice underwent a noticeable transformation with the introduction of power-operated water lifting technologies. For example, the introduction of pumps between 1963–1966 ensured adequate water supply for Boro rice production during the dry season (December-April) [85,86]. Low-lifting pumps (LLPs), known locally as shallow pumps, and deep submersible pumps (DSPs) (Fig 5) were identified as the most commonly used water lifting technologies in the Krishnanagar and Mathureshpur Unions.
The main limitations to the use of DSPs, as elicited by both KII and FGD participants, include the availability of high-quality aquifers, reduced groundwater tables, and high installation costs. Furthermore, the availability of DSPs was limited in the study area. One KII respondent who is a farmer in Krishnanagar Union and owned a DSP outlined the costs of using this technology:
The average installation cost of an electricity-driven deep submersible pump with a capacity of 150 horsepower and a boring depth of more than 200 m is 500,000 Taka [US $4,500]. In addition, the maintenance cost of this pump is nearly 5,000 Taka [US $47] per year. The monthly electricity cost to operate this technology is 10,000 Taka [US $95]. This submersible pump can fulfill the water demand for irrigation of 1,320 decimal agricultural land.
Both KII and FGD participants noted that the DSP technology is primarily used to meet irrigation demand during the four-month Boro rice growing season. DSPs are primarily owned by local elites and financially solvent stakeholders, who have become vendors for water supply for irrigation during the dry season. Water is supplied to farmers’ lands via flexible rubber hose pipes connected to the DSP, which is located elsewhere—typically on the owner’s land. The respondents noted that it costs approximately US$40 to have irrigation water supplied to 33 decimals of agricultural land for the entire four-month Boro rice growing season. Overall, 45.33% of the household survey respondents (n = 300) rated DSP as an effective technology due to its effectiveness in meeting the farmers’ water demands during the dry season. In the study area, KII (n = 15) and FGD respondents (n = 80) further substantiated that access to this technology created opportunities for farmers to expand their rice cultivation to the dry season, as they had been previously confined to cultivating Aman rice during the monsoon season (July-November) due to water scarcity and extreme salinity during the dry season.
Compared to DSPs, KII participants found the LLPs are cost-effective and easy-to-use. The average cost to install an LLP with a boring depth of less than 76.2 m is approximately US$1,000. The majority of LLPs in the study area were diesel driven. However, although LLPs are a cost-effective option for satisfying irrigational water demand, this technology was rated by the household survey respondents (n = 300) as being a less effective adaptive strategy for mitigating climate-induced stress on water resources compared to DSPs (Fig 4). Farmers mostly used LLPs when they had no facilities or access to a DSP, or when they were unable to install a DSP due to the lack of a good groundwater aquifer and extreme salinity intrusion into the groundwater. In contrast, farmers in areas with comparatively lower salinity intrusion preferred to use LLPs to meet their irrigational water demand. This technology was also used to lift water from the river to the gher, which is a modified field with peripheral dikes for shrimp farming. In the Krishnanagar Union, local people’s livelihoods mostly depended on agriculture; hence, the number of people using both LLPs and DSPs was quite sizeable compared to the Mathureshpur Union (Tables 2 and 3).
4.3. Dynamics of adopting technology-based adaptations
4.3.1. Adoption process.
The dissemination of information and knowledge relating to technology-based adaptations significantly influences their adoption to mitigate climate-induced water scarcity. The roles played by various stakeholders and media in spreading knowledge and encouraging the adoption of technology in the study area are shown in Fig 6. In recent years, electronic media, such as television and radio, have emerged as significant mediums for disseminating information about technology-based adaptation across social groups.
Source: Collected field data 2022.
Community-based organizations and members from neighboring communities also played a critical role in educating the respondents about technology-based adaptation to water scarcity, as such local-level engagement can help to overcome barriers to behavioral change and values impeding the adoption of new technologies. A KII respondent-farmer in Krishnanagar Union who owned a DTW and DSP highlighted the importance of community engagement in facilitating technology adoption:
Prior to 2018, we cultivated rice only in the Aman season, where rainwater was the primary water source. Due to lack of water availability and extreme salinity, we could not cultivate rice in the Boro season. I learned from some farmers in our neighboring community who started producing rice in the Boro season on a limited scale by installing diesel-powered submersible pumps to withdraw groundwater for irrigation. Since then, I’ve been interested in harvesting rice on my arable land during the Boro season, but I was concerned that the location of my village is considerably closer to the coastal river area, where salinity intrusion poses the greatest difficulty. Initially, I assessed the possibility of having a good soil layer to extract water from a groundwater aquifer on my land by installing a hand-driven deep tube well. Then I installed the deep submersible pump with the help of a third-party contractor. These efforts worked very well.
Highlighted by the KII and FGD respondents, NGOs, INGOs, and local government representatives, including those from Upazila and Union Parishad, also served as essential communication channels by promoting technology-based adaptations in the water sector and organizing training programs at the community level. Furthermore, local governing bodies, particularly the DPHE, played a vital role in supporting community members who lacked financial means, but were interested in adopting adaptive technologies. Individuals seeking to adopt these technologies were only required to contribute service fees, which were substantially reduced, with the remaining expenses being partially subsidized. Similarly, NGOs and INGOs played a crucial role in the adoption of high-cost technology (e.g., RO) within the community through the implementation of two models: a hybrid subsidy model wherein they partially covered the implementation costs for interested individuals, and a locally-operated fee-based business model for operation and maintenance. These interventions have resulted in the rapid adoption of adaptive technologies at the community level, which has significantly alleviated climate-change-induced water crises.
4.3.2. Access to technology.
Our field data revealed disparities between socioeconomic groups in the Krishnanagar and Mathureshpur Unions regarding access to technology and its benefits for mitigating climate-induced water stress (see Table 4). In the Krishnanagar Union, individuals had greater access to DTWs (compared to RWH and RO) for securing adequate water supply. Specifically, 45.14% of the household survey respondents (n = 144) from this Union had a DTW on their property, while 50.69% of respondents who did not have a DTW had access to one owned by someone else. Access to the RO is noticeably limited owing to the unavailability of quality groundwater aquifers in this area. As the majority of people in Krishnanagar Union lived in poverty, they found it challenging to purchase drinking water from RO plants. Most RO plants are located in neighboring unions, and the additional transportation costs, combined with the water price, function as disincentives from using this source of drinking water by the residents in Krishnanagar (Table 4). For households without an RWH system, DTW, or access to an RO plant—but that did have access to someone else’s DTW—the average round-trip distance to fetch drinking water was approximately 874 meters. In most of these households, the women were largely responsible for fetching potable water from distant sources to meet their household’s drinking water demand. A farmer from Krishnanagar Union shared during the interview:
Rising salinity intrusion has made accessing quality groundwater a serious challenge in our village. Over time, many in our community have tried deep boring to locate suitable aquifers for installing reverse osmosis systems with our limited resources. While a few were successful, the majority faced difficulties in finding usable groundwater for drinking and irrigation purposes.
Due to its fee-based business model, access to RO-produced drinking water was entirely dependent on whether a household could afford it. The majority of respondents in the study area relied on RO for its ability to reliably supply of safe water, as well as due to the limitations of RWH during the dry season. Households that cannot afford home delivery, it is the women from those households who are typically tasked with fetching water from the RO plant. For households that relied on RO but could not afford the delivery charge (and that did not have access to RWH or DTW), the average round-trip distance to fetch water was 1993.34 meters. Installing RO systems in these localities requires substantial capital-cost, and mobilizing such resources from government and non-government organizations remains a significant challenge. As agricultural activity in this Union has become significantly limited due to salinity intrusion, the use LLPs and DSPs is considerably low. However, a handful of wealthy shrimp cultivators have access to LLPs and use them to carry saline water into their ghers for shrimp farming.
Locals in the Krishnanagar Union who owned or had access to a DTW preferred to use this technology to meet their domestic water demands. Aside from DTWs, the KII and FGD responses indicated that people also still relied on pond water and rainwater collected through traditional means to satisfy their domestic and personal water demands. As most people in Krishnanagar Union depended on agriculture for their livelihood, a significantly larger proportion of household survey respondents in this Union had access to LLPs and DSPs [89% (n = 144) compared to 17.07% in Mathureshpur Union (n = 156)], which they used to fulfill their agricultural water demands (Tables 2 and 3). In contrast, in Mathureshpur Union, where available water sources were significantly affected by salinity intrusion, and the availability of RO and RHW in this Union compared to Krishnanagar has facilitated greater reliance on these technologies then DTWs to get fresh drinking water (Table 4). Although Mathureshpur Union has four community-based RWH cisterns where locals can collect water, 72.44% of household survey respondents (n = 156) reported having a RWH system in their home, which significantly helped to fulfill their drinking and domestic water needs.
4.3.3. Disparities in resources distribution.
The field investigation revealed wide disparities in the distribution of resources and benefits from modern technologies. In the study area, RO technology has become essential for everyday life due to its ability to efficiently provide safe water throughout the year. However, RO plants are expensive to construct, and NGOs and INGOs only provide financial support to financially secure individuals, thus resulting to a locally-owned business model. The FGD respondents (n = 80) noted that although NGOs typically impose specific standards for RO plant operation, such as making water affordable and providing it free of charge to the disabled, these requirements are often not followed. As noted above, most residents in the study region lived in poverty and struggled to access drinking water from RO plants due to affordability issues (Table 5).
Economically disadvantaged communities that purchase water from RO plants but cannot afford home delivery services disproportionately suffer from severe hardship, especially the women, as they are often the ones who must fetch water for their families. During an FGD session, a female farmer expressed concern about the suffering of community members who depend on RO for drinking water, particularly during the peak of the COVID-19 pandemic in 2020.
Although the installation of RO plants has significantly reduced the community’s struggle with drinking water scarcity, it is still extremely difficult for poor individuals to collect water due to their limited financial resources. Nonetheless, they still manage to collect water from the RO plant because the acceptance and reliability of this technology in providing adequate drinking water supply are high. The situation worsened during the pandemic when the water supply from the RO plant, which serves the majority of the village, was halted for nearly six months as a precautionary measure to prevent the spread of the virus. During this time, some community members were forced to collect water from far-off sources, while others relied on pond water to meet their needs.
Another major disparity observed in the study area, as revealed by the KII and FGD participants, was the uneven access to water resources for irrigation, particularly regarding the use of DSPs, as these pumps are predominantly owned by wealthier individuals and local elites, with limited support on the part of NGOs or governmental entities. When it comes to providing water for irrigation during the dry season, priority is given to wealthy farmers and the elite class who own more arable land. The lack of financial resources to install DSPs (Table 5), the absence of high-quality groundwater aquifers, and the use of the pump’s maximum capacity to supply water to wealthy farmers and local elites results in poor and marginalized farmers being deprived of access to these resources. Thus, these marginalized farmers suffer most from water scarcity for irrigation.
Additionally, despite the government’s extension of financial assistance to community members, most participants in the FGDs who owned one or more of the aforementioned technologies did not receive any financial support to install them. They explained that favoritism is prevalent in the local government and other institutions in allocating such funds, which deprives poor and marginalized people of financial support that could be used to implement technology to alleviate climate-induced water stress.
4.3.4. Constraints and barriers.
The expansion of advanced groundwater-based technology in the study area faces significant challenges due to salinity intrusion. According to the KII and FGD participants, the majority of STWs in the study area, as well as some DTWs, ROs, and DSPs, have failed or become less effective at providing an adequate water supply due to groundwater aquifer failure caused by extreme salinity. Despite the need for advanced technology (e.g., RO, DTWs, and DSPs) in these regions, installing and expanding such equipment near shrimp farming areas is almost impossible because the saline water used for shrimp farming infiltrates and significantly pollutes groundwater aquifers.
Although the impacts of climate change are not discriminatory, disadvantaged groups are disproportionately affected by unequal access to resources that could help them implement adaptive technologies, thus making it more difficult for them to mitigate water stress. Financial barriers to acquiring these technologies in the water sector have limited the adaptation process, as most people in the study area live in poverty. Furthermore, as Bangladesh is an LMIC, limited budgets for climate finance and uneven distribution of resources create inequalities in society such that the wealthy and elite class obtain most of the benefits from technology-based adaptation approaches. Moreover, most respondents in the participatory research reported that development activities conducted by NGOs had substantially decreased, especially those involved with providing microfinance in Kaliganj Upazila after the emergence of Rohingya refugee crisis in Bangladesh in 2017.
5. Discussion
Similar to other LMICs and areas of Bangladesh [60,70,71,89], STWs, DTWs, and RWH were the most commonly used adaptation technologies at the household level in the study area. Technology-based adaptations used at the community level included PSFs, RWH, DTWs, and RO [60,79]. The increased availability of LLPs and DSPs significantly helped to alleviate irrigation water crises during the dry season and expand agricultural activities in the study area. With regards to climate change adaptation, the outcomes of adopting and implementing such technologies conform with the findings of Bell et al. [90].
Especially high levels of effectiveness of various technologies were found to be particularly high for RO, DTWs, and DSPs, which have been implemented in parts of the study area with comparatively low levels of salinity. These technological measures were adopted in consideration of the limitations and lesser availability of high-quality groundwater aquifers. It is important to note that the majority of these highly efficient technologies rely on groundwater as the primary source. This high dependency, along with the excessive extraction of groundwater, places immense pressure on the water table, which leads to its reduction and, ultimately, the lateral intrusion of saline water from the sea into coastal groundwater aquifers [17,18]. The integration of environmental factors and maximization of technological efficiency requires capacity building in community members, which can be achieved via community-focused approaches aimed at reducing dependency on groundwater-based technologies and encouraging the adoption of environmentally friendly alternatives, such as RWH (Fig 1).
A household’s socioeconomic status plays a pivotal role in determining its vulnerability to crises or hazards. This is especially true of Bangladesh’s coastal areas [60]. The high proportion of low-income groups and agriculture-based livelihoods in the study area makes it particularly vulnerable to climate-induced water crises. With regards to the adoption process, the ability of community members to afford adaptive technologies was the most crucial factor affecting whether they were adopted and installed. Additionally, stakeholder influence was also critical to the dissemination of information and diffusion of knowledge relating to technology-based adaptations and the distribution of resources and the benefits of adopting such technologies. Empirical studies [47,48,50,91] have found that limited access to public goods and services, unequal distribution of wealth and benefits, and unequal participation in the decision-making process negatively impact rural communities’ adaptive capacities with respect to reducing the effects of climate change. Furthermore, these conditions also reinforce and exacerbate pre-existing inequalities in society, particularly for marginalized groups, including women; the findings of our study reaffirm this relationship.
Studies in various LMICs in Africa and South Asia have found that the distribution of and access to resources is often unequal and subject to favoritism and power dynamics between local stakeholders [92–94]. For instance, in Gurgaon, India, the majority of adaptive facilities (e.g., DTWs) are owned by local elites, while favoritism and power dynamics regarding water distribution have forced the affected poor communities to use saline water for drinking and irrigation. The same factors and outcomes were observed in the study area of the present study (i.e., Bangladesh’s coastal communities). In addition, the lack governmental monitoring over the use of these technologies also contributed to inequalities in access to resources and the distribution of benefits among the communities. These findings align with those of studies conducted in LMICs in Africa. For example, in East African countries—where DTWs, motorized pumps, and drip irrigation are the most common technology-based adaptive actions—ineffective monitoring by governing institutions has resulted in social discrimination [92]. Similarly, in Ethiopia, water distribution is exclusively controlled by community leaders known as “Abo Mai,” which has resulted in inequitable resource distribution, as there is little oversight on the part of the appropriate governing bodies [94]. In our study area, low budgets and ineffectiveness on the part of governing authorities also resulted in the poor monitoring of resource allocation and the distribution of water using such technologies, which in turn amplified inequality within Bangladesh’s coastal communities.
As in the above-discussed technology-based adaptation studies, we found that the operational standards set by donors to maintain equity in distributing the benefits of advanced technologies (e.g., RO, DTWs, and DSPs) were not being followed. In most cases, advanced technologies were owned by elite and wealthy groups, who consequently enjoyed the lion’s share of the benefits. Our findings revealed the prevalence of discrimination in access to governmental financial facilities—and thus, the ability to adopt such technologies—as such access is often determined based on favoritism. Additionally, affordability is a primary barrier to the use of these technologies to reduce water vulnerability, as attempts to scrape together the funds to acquire such technologies often create financial stress for poor and marginalized communities. The reduced availability of these technologies in more saline-affected areas further creates suffering and hardship for marginalized communities, as it is more difficult to obtain safe water using these technologies and women are often required to fetch clean water from distant sources. A large portion of the poor and marginalized households in the studied communities that lacked access to such technologies (due to either availability and affordability) still relied on pond water and traditional RWH methods using plastic or cloth, followed by filtration with Potassium Alum (known locally as Fitkari) and boiling.
Although groundwater-based technologies were highly preferred, RWH was rated by the participants as moderately effective and was widely recognized by stakeholders as the most sustainable technology for ensuring water security at the household level [73]. Unfortunately, most of the community-based RWH systems had become dysfunctional due to lack of maintenance. Thus, local leaders and community members must take responsibility for the maintenance of such community-based RWH technologies, as doing so will significantly reduce water stress for marginalized households that cannot afford water from RO plants. The governing authorities and NGOs also have a major responsibility to provide more training on climate change adaptation and the maintenance of such technologies to alleviate climate-induced water stress at the community and household level.
Nonetheless, pretreating the primary water used in RO systems and deploying RO plants in more saline-affected areas, particularly those adjacent to the coastal belt, would be able to ensure an adequate water supply and benefit thousands of poor and marginalized households. Recent studies have demonstrated that “coagulation,” which aids in the initial destabilization of suspended solids in the water, is an effective pretreatment process for RO systems [95–98]. For instance, Tabatabai et al. [99] evaluated the efficacy of coagulation for removing organic matter from seawater, with findings indicating that it possesses immense potential for removing suspended solids and enhancing membrane longevity. While the cost to install RO systems with sophisticated facilities may high, such investments promise significant returns, as they can reduce membrane fouling and operational expenses and boost the availability of RO technology in saline-affected areas, thus alleviating climate-induced stress on drinking water accessibility.
6. Conclusions
This study pursued a key scientific research question to explore what technology-based adaptation measures are being adopted in alleviating water scarcity; and what are the processes and underlying factors involved in expanding these adaptive approaches in southwestern coastal communities of southwestern Bangladesh. This work thus makes a novel contribution to the literature concerning the nature and extent of adoption of technology in water related adaptation in coastal regions.
Our research findings address a significant knowledge gap by providing valuable insights into the effectiveness of the identified technology-based adaptation measures and how they can be expanded further among the coastal communities. Specifically, our findings reveal that technology-based adaptation approaches noticeably reduced climate-induced stress related to the availability of water drinking and irrigation purposes. Furthermore, reaffirming Rogers’s [29] Diffusion of Innovation theory, community-based organizations, members from neighboring communities, and electronic media were all found to play critical roles in the diffusion and adoption of these technologies. These communication and mobilization channels served to enhance awareness about various adaptation options among community members. Notably, financial assistance from GOs, NGOs, and INGOs has made it easier to adopt such adaptation technologies to reduce water scarcity.
Grounding on the findings of our research, we recommend the following to inform future policies:
- a). Given the inadequate availability of data and knowledge regarding the effects of technology adoption in water sector, it is necessary to develop effective systems for monitoring groundwater-based technologies, as such systems will be key in ensuring equitable access to water resources, especially by poor and marginalized community members. The primary determinant for community adoption of technological water services is affordability. To ensure equitable access, authorities must establish and enforce operational standards, prioritizing marginalized populations. Transparent monitoring mechanisms, including water meters and advanced engineering tools, are essential for accountability. A publicly accessible database detailing the number, location, extraction, and supply of water technologies, along with their operational status, is also recommended.
- b). To alleviate climate-change-induced stress in the water sector, program and policy development should prioritize transparency and devoting a larger portion of the budget to climate-related initiatives aimed at promoting the adoption of appropriate adaptation technologies. Groundwater-based technologies like RO, DTW, and DSP effectively supply drinking and irrigation water. However, over-extraction depletes groundwater levels and increases saline intrusion into coastal aquifers. The use of sustainable technologies such as RWH should be increased at the household and community levels, as such methods will undoubtedly enhance access to fresh water and reduce reliance on groundwater-based methods.
- c). RO systems are typically deployed in areas with lower salinity due to the limited availability of fresh groundwater and reduced maintenance costs. Pretreatment facilities into RO plants should be incorporated as deploying this technology in more saline-affected will significantly reduce reliance on a single water source (e.g., high-quality groundwater aquifers) and improve the wellbeing of community members and mitigate water vulnerability in the region.
- d). Advocate for transparency in fund allocation by governing bodies for technology-based adaptations, including supplementary subsidies and tax incentives. Equitable access to such technology across socioeconomic groups should be prioritized in order to ensure equity and equality with respect to access to water.
Supporting information
S1 Table. Socioeconomic characteristics of the sampled households (n = 300).
https://doi.org/10.1371/journal.pclm.0000460.s001
(DOCX)
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