Brahmaputra Research Articles

A decision‐led evaluation approach for flood forecasting system developments: An application to the Global Flood Awareness System in Bangladesh

AbstractScientific and technical changes to flood forecasting models are implemented to improve forecasts. However, responses to such changes are complex, particularly in global models, and evaluation of improvements remains focussed on generalised skill assessments and not on the most relevant outcomes for those taking decisions. Recently, the Global Flood Awareness System (GloFAS) flood forecasting model has been upgraded from version 2.1 to 3.1 with a significant change to its hydrological model structure. In the updated version 3.1, a single fully configured hydrological model (LISFLOOD) has been adopted, including ground water and river routing processes, instead of two coupled models, a land surface and a simplified hydrological model, of the previous version 2.1. This study aims to evaluate changes in the simulated behaviour of floods and the forecast skill of the two GloFAS versions based on different decision criteria for early action. We evaluate GloFAS reforecasts for the Brahmaputra and the Ganges Rivers in Bangladesh for the period 1999–2018. For the Brahmaputra River, the old GloFAS 2.1 version performs better than the 3.1 version, especially in predicting low‐ (90th percentile) and medium‐level (95th percentile) floods. For the Ganges, GloFAS 3.1 shows improved probability of detection of low‐ to medium‐level floods compared to version 2.1, especially for lead times longer than 10 days. Both versions show limited skill for more extreme floods (99th percentile) but results are less robust for these less frequent floods given the lower number of events. Using lead‐time dependent thresholds improves the false alarm ratio while reducing the probability of detection. The changes in model structures influence the model performance in a complex and varied way and forecast skill needs further investigation across regions and decision‐making criteria. Understanding the skill changes between different model versions is important for decision‐makers; however, focused case studies such as this should also be used by model developers to guide future changes to the system to ensure that they lead to improvements in decision‐making ability.

The Himalayan uplift and evolution of aquatic biodiversity across Asia: Snowtrout (Cyprininae: Schizothorax) as a test case.

Global biodiversity hotspots are often remote, tectonically active areas undergoing climatic fluctuations, such as the Himalaya Mountains and neighboring Qinghai-Tibetan Plateau (QTP). They provide biogeographic templates upon which endemic biodiversity can be mapped to infer diversification scenarios. Yet, this process can be somewhat opaque for the Himalaya, given substantial data gaps separating eastern and western regions. To help clarify, we evaluated phylogeographic and phylogenetic hypotheses for a widespread fish (Snowtrout: Cyprininae; Schizothorax) by sequencing 1,140 base pair of mtDNA cytochrome-b (cytb) from Central Himalaya samples (Nepal: N = 53; Bhutan: N = 19), augmented with 68 GenBank sequences (N = 60 Schizothorax/N = 8 outgroups). Genealogical relationships (N = 132) were analyzed via maximum likelihood (ML), Bayesian (BA), and haplotype network clustering, with clade divergence estimated via TimeTree. Snowtrout seemingly originated in Central Asia, dispersed across the QTP, then into Bhutan via southward-flowing tributaries of the east-flowing Yarlung-Tsangpo River (YLTR). Headwaters of five large Asian rivers provided dispersal corridors from Central into eastern/southeastern Asia. South of the Himalaya, the YLTR transitions into the Brahmaputra River, facilitating successive westward colonization of Himalayan drainages first in Bhutan, then Nepal, followed by far-western drainages subsequently captured by the (now) westward-flowing Indus River. Two distinct Bhutanese phylogenetic groups were recovered: Bhutan-1 (with three subclades) seemingly represents southward dispersal from the QTP; Bhutan-2 apparently illustrates northward colonization from the Lower Brahmaputra. The close phylogenetic/phylogeographic relationships between the Indus River (Pakistan) and western tributaries of the Upper Ganges (India/Nepal) potentially implicate an historic, now disjunct connection. Greater species-divergences occurred across rather than within-basins, suggesting vicariance as a driver. The Himalaya is a component of the Earth's largest glacial reservoir (i.e., the "third-pole") separate from the Arctic/Antarctic. Its unique aquatic biodiversity must be defined and conserved through broad, trans-national collaborations. Our study provides an initial baseline for this process.

Identifying the stability trajectory of a large braided Brahmaputra river using reach-scale process-based approach

The dynamic evolution of a large braided river system is characterized by sporadic operation, impacted by a diverse range of natural and anthropogenic factors. The hydro-geomorphological interaction within the river corridor and its surrounding ecosystem presents a complex process, posing challenges in comprehending its dynamics. This study investigated the spatiotemporal heterogeneity in the vegetation-flow regime of a large braided reach of mighty Brahmaputra river. A detailed statistical analysis for the last three decades (1990 to 2019) was performed to demonstrate the in-stream vegetation characteristics for the selected middle reach (240 km) of the river. Google earth engine platform and advanced geospatial techniques have been used in this study. A novel indicator called stability trajectory indicator was developed that utilized vegetation information to identify the stability state of braided reaches. The findings of this study indicate a substantial increase in moderate and dense vegetation cover compared to light vegetation cover over the past decade. These results highlight the pronounced influence of increased moderate and dense vegetation type on the stability criteria of the reach, surpassing the contribution of light vegetation. The approach outlined in this study holds potential for river engineers to develop an effective management strategy for monitoring and maintaining river health.

Characterization and Upgrading of Low-grade Brahmaputra River Basin Ilmenite Concentrate: Exploring an Alternate Feedstock for Synthetic Rutile Preparation

Characterization and Upgrading of Low-grade Brahmaputra River Basin Ilmenite Concentrate: Exploring an Alternate Feedstock for Synthetic Rutile Preparation

Projected Discharge of Dudhnai River: A Tributary of the Brahmaputra River

Projected Discharge of Dudhnai River: A Tributary of the Brahmaputra River

Assessment of Changes in Brahmaputra River Course at the Pagladia Confluence Point using Remote Sensing and GIS Techniques

The river Brahmaputra is a large alluvial river that is prone to frequent bank erosion and channel pattern changes, leading to significant shifts in its course. This study aimed to analyze these changes along a 56-kilometer stretch of the river using a combined approach of remote sensing and GIS techniques. This study utilized USGS and Landsat 8 satellite imagery to map the river's channel configuration from 1985 to 2022, providing valuable insights into the river's morphology and the stability of its banks. Additionally, the analysis provided information on changes in the river's main channel which can help in predicting future behavior and mitigating the impact of these changes. The findings of this study have significant implications for river management, allowing for informed decision-making and improved strategies for protecting communities and infrastructure located along the river's course.

Contesting in the policy sphere: stakeholders and policy formulation on the lower Subansiri dam in the Northeast

ABSTRACT We advance a framework for analysis of democratic contestation in the policy and media spheres, in the context of the interest group theory and the stages of public policy evolution, to assess whether the contestation process favors some stakeholders over others in India, with a model that predicts pro- or anti-dam policy discourses in the news. There is evidence from participation in environmental movements, especially in the case of anti-dam protest groups, in the policy sphere that play a role in the contestation of scientific knowledge. Our core concern is to understand whether representation of the voices of non-governmental organizations (NGOs) and protest groups in the news media affects public policy on controversial mega-projects such as the building of a mega-dam. Our focus is on the timely and critically important case of the Lower Subansiri Hydro Electric Project (LSHEP), a mega-dam on the border of Assam and Arunachal Pradesh, the highest earthquake zoned states through which runs the mighty Brahmaputra river. The mega-dam construction was suspended after widespread protests led by social and environmental activists in 2010–11. However, the construction resumed after the election of the BJP-led national government in 2014 and in the state of Assam in 2016. The revival precipitated a new phase of democratic contestation in the policy sphere in 2015–17 which is modeled here, based on content analysis of news reporting. We find that in the policy sphere, the voices of anti-dam activists did not succeed in fostering an anti-dam frame in the news media in the form of news stories opposing the dam.

Ichthyofaunal Diversity of Tipkai River in Assam, India

Assam is endowed with dynamic rivers and lakes which in turn facilitates a rich diversity of fish species. The western Assam geographically blessed with such a river named Tipkai. Tipkai River is a Himalayan tributary of the Brahmaputra River in the Indian state of Assam which raises in the Bhutan hills flows through the Kokrajhar (BTR) and through Dhubri district of Assam and joins the Brahmaputra River at Chatakurachar of Dhubri district. The present study deals with the extensive Ichthyological fields survey conducted over a period of oneyear from January 2021 to December 2022 based on the data collected from six locations of the river from the Mahamaya (Bagribari) to Chatakurachar. The survey revealed the occurrence of great range of diversity of fishes representing 106 species distributed under 10 orders and 31 families. Among the recorded fish species 4 species are Vulnerable (VU), 2 species are Near Threatened (NT), 3 species are Endangered (EN),86 species are least concern (LC) while 3 species are Not Evaluated (NE), 2 species are Data Deficient (DD) with 65 genus, 10 order and 30 families. The highest order Cypriniformes with 49 species, Siluriformes 27 species Perciformes 17 species. The site Khoraghat represents the lowest fish diversity among the six sites during the study period might be due to sand mining and other anthropogenic reasons which needs further analysis of water quality. Thus, this beautiful river, a small tributary from Bhutan serves the land cover and maintains its beautiful biodiversity and also the lifeline for mankind.

Quantifying the relative contributions of climate change and ENSO to flood occurrence in Bangladesh

Bangladesh is highly vulnerable to flood hazards, and its flood risk is projected to increase with global warming. In addition to climate change, internal climate variation, such as the El Niño–Southern Oscillation (ENSO), influences flooding in many rivers worldwide. However, the impact of internal climate variability on flooding in Bangladesh remains unclear due to the limited observations. Here, we assess the impacts of ENSO and climate change on flood occurrence in Bangladesh using a large-ensemble climate simulation dataset and a global river model (CaMa-Flood). After separating 6000 years of simulation (100-member ensemble river simulations for 1950–2010) into El Niño, La Niña, and neutral years, we calculated the extent to which each ENSO stage increased flood occurrence probability relative to the neutral state using the fraction of attributable risk method. In addition, we estimated the impact of historical climate change on past flood occurrence through a comparison of simulations with and without historical global warming. Under the no-global-warming climate, La Niña increased the occurrence probability of a 10 year return period flood at Hardinge Bridge on the Ganges River by 38% compared to neutral years. The influence of La Niña or El Niño state on flood occurrence probability in the Brahmaputra River at Bahadurabad station is negligible. Historical global warming increased the occurrence of flooding in the Ganges River, the Brahmaputra River, and their confluence by 59%, 44%, and 55%, respectively. The impact of ENSO on flood occurrence probability decreased in the historical simulation, likely due to the conflation of ENSO and climate change signals, and no significant correlation between ENSO and flood occurrence was detected when only small-ensemble simulations were used. These findings suggest that the use of large-ensemble climate simulation datasets is essential for precise attribution of the impacts of internal climate variability on flooding in Bangladesh.

Luminescence fingerprints fluvial sediment transport from the Tibetan Plateau to the Bangladesh Delta

Fluvial sediment fingerprinting employs various methods, directly link sink and source. However, the identification and quantification of the transformation that sediments experience during fluvial transport remain unclear. The luminescence properties of quartz and K-feldspar change during the burial/exposure to sunlight cycles undergone by fluvial sediments, potentially allow scientists to trace fluvial sediment transport. Here, we report on changes in luminescence properties in active river bars from source to sink along the Yarlung Tsangpo-Brahmaputra River system. Optically stimulated luminescence (OSL) sensitivities and residual doses of quartz and K-feldspar within the fluvial sediments are used for the fingerprint method. Source rock is identified as the primary determinant of regional variations in quartz OSL sensitivities within fluvial sediments along the Yarlung Tsangpo River, while transportation distance governs local changes. Samples from narrower river channels with higher normalized channel steepnesses (Ksn) along the Yarlung Tsangpo River exhibit higher residual doses. Furthermore, the Brahmaputra River exhibits higher residual dose values compared to the Old Brahmaputra River. The sediments' residual doses are therefore employed to fingerprint fluvial erosion ability. Our luminescence fingerprint results indicate that coarse-grained fractions experience a “dilution” effect due to the input of new sediments after traveling approximately 50-200 km along the Yarlung Tsangpo River and about 50-100 km along the Brahmaputra-Old Brahmaputra River course. The comparison of luminescence (quartz and feldspar) and detrital zircon fingerprinting within the fluvial sediment holds the potential to trace weathering and erosion cycles during transportation in large river contexts.

Ganges River Dolphin (Platanista gangetica gangetica): An Indicator of Ecosystem Health in the River Basins

Along with turtles, crocodiles, and a few different species of sharks, the Ganges river dolphin (Platanista gangetica gangetica) is one of the oldest animals on the planet. The Ganges and Brahmaputra river basins in India, Nepal, and Bangladesh are home to this species. It generally lives in countercurrent systems of the main river channel and feeds mostly on fish. The Gangetic river dolphin is considered important because it acts as an indicator of the health of the overall river ecosystem. It was designated as the National Aquatic Animal of India on 5 October 2009. This species is now extinct in most of the areas where it once existed, due to serious threats from water development projects, pollution, poaching, and deaths from accidental entanglement in fishing gear. Currently, their population is estimated to be less than 2000 individuals. The Ganges river dolphin comes under Schedule I of the Wildlife Protection Act (1972). They are classified as Endangered in the IUCN Red List and included in CITES Appendix I. The Wildlife Institute of India launched an initiative called "Development of a Conservation Action Plan for Dolphins" in 2016 with the intention of saving these endangered dolphins.

River bank erosion vulnerability demarcation based on the sensitivity analysis of geotechnical parameters: Majuli Island, India

The present study assesses the vulnerability of the river bank area most sensitive to erosion by combining the data obtained from existing literature and performing numerical simulation using finite element-based numerical code. Various geotechnical parameters, like average particle size (D50), Plasticity Index (PI), Elastic Modulus (E), Dry Unit Weight (γd) or Saturated Unit Weight (γsat), Coefficient of Permeability (k), Undrained Shear Strength (cu), Moisture Content (w%) and soil types based on the Unified Soil Classification System (USCS), were taken into account. Weighted Ranking Analysis (WRA) was performed based on the sensitivity of relevant geotechnical factors affecting bank erosion. The results indicate that the areas influenced by the Subansiri River (western bank) and the Brahmaputra River (southern bank) fall in the highly vulnerable zone category, while the Luhit and Kherkutia Suti Rivers (northern bank) fall in the moderately vulnerable category to river bank erosion.

Distribution and Genesis of Wetlands in Nagaon District, Assam: A Geomorphological Perspective

Assam is endowed with a large number of wetlands of different kinds. The number and areas of wetlands are variously distributed over the state. Assam has a total wetlands area of 1012 sq.kms with 3514 wetlands representing the highest area under wetlands among the North Eastern states. More than 80 percent of the wetlands falls in Assam regions, which suggest that majority of the regions wetlands originates in the fluvial domain of the Brahmaputra River system. Wetland distribution in district level reveals that Nagaon District has the highest number of wetlands among all the districts of the state. Depending on their locational characteristics, the wetlands are prone to various kinds of geo-environmental problems. Therefore, with growing need of wetlands management, it has become highly imperative to study genesis and development of wetlands.

Matrilineal phylogeny and habitat suitability of the endangered spotted pond turtle (Geoclemys hamiltonii; Testudines: Geoemydidae): a two-dimensional approach to forecasting future conservation consequences.

The spotted pond turtle (Geoclemys hamiltonii) is a threatened and less explored species endemic to Bangladesh, India, Nepal, and Pakistan. To infer structural variation and matrilineal phylogenetic interpretation, the present research decoded the mitogenome of G. hamiltonii (16,509 bp) using next-generation sequencing technology. The mitogenome comprises 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs), and one AT-rich control region (CR) with similar strand symmetry in vertebrates. The ATG was identified as a start codon in most of the PCGs except Cytochrome oxidase subunit 1 (cox1), which started with the GTG codon. The non-coding CR of G. hamiltonii was determined to have a unique structure and variation in different domains and stem-loop secondary structure as compared with other Batagurinae species. The PCGs-based Bayesian phylogeny inferred strong monophyletic support for all Batagurinae species and confirmed the sister relationship of G. hamiltonii with Pangshura and Batagur taxa. We recommend generating more mitogenomic data for other Batagurinae species to confirm their population structure and evolutionary relationships. In addition, the present study aims to infer the habitat suitability and habitat quality of G. hamiltonii in its global distribution, both in the present and future climatic scenarios. We identify that only 58,542 km2 (7.16%) of the total range extent (817,341 km2) is suitable for this species, along with the fragmented habitats in both the eastern and western ranges. Comparative habitat quality assessment suggests the level of patch shape in the western range is higher (71.3%) compared to the eastern range. Our results suggest a massive decline of approximately 65.73% to 70.31% and 70.53% to 75.30% under ssp245 and ssp585 future scenarios, respectively, for the years between 2021-2040 and 2061-2080 compared with the current distribution. The present study indicates that proper conservation management requires greater attention to the causes and solutions to the fragmented distribution and safeguarding of this endangered species in the Indus, Ganges, and Brahmaputra (IGB) river basins.

Historical and projected evolutions of glaciers in response to climate change in High Mountain Asia

Glacier changes are regarded as the conspicuous icon of climate change in High Mountain Asia (HMA) alpine environments. Multi-temporal glacier coverage is essential for mass balance estimations and understanding glacial changes in response to climate variability. However, consistent multi-temporal glacier area datasets across the HMA are limited due to challenges posed by seasonal snow and cloud cover in remote sensing satellite images. In this study, a new method is proposed to estimate glacier and nonseasonal snow (GNS) areas by combining the normalized difference snow index (NDSI) and bright temperature bands from Landsat remote sensing images in 1990s, 2000s, 2010s and 2020s. Meanwhile, the integrated ice dynamic Open Global Glacier Model (OGGM) is applied to simulate nine typical glaciers and project their changes using 15 general circulation models (GCMs) under four shared socioeconomic pathways (SSPs). The results showed that total GNS areas in HMA were estimated at 71.26 × 103 km2 in the 1990s, and decreased to 53.17 × 103 km2 in the 2020s. Massive proportions of GNS were mainly distributed in the southeast and northwest region. Tipping points of GNS indicating a transition from mass balance gain to loss during four periods were detected in the Upper Tarim basin, Inner Tibetan Plateau, Upper Yangtze river basin, Upper Brahmaputra river basin, and Upper Salween river basin. The reduction of total GNS area was attributed to significantly rising temperature and decreasing solid precipitation. The projections indicate that glacier shrinkages will be the dominant trend in the future, and most typical glaciers will experience a mass loss of 60% under SSP245 (SSP2-RCP4.5) and over 90% under SSP585 (SSP5-RCP8.5) by the end of the century. The response of glaciers to climate change is also found to be influenced by factors including local topography and elevation ranges. The findings of this study provides a better understanding of glacial dynamics in response to climate change and highlights the importance of making water resources management strategies to mitigate the influence of glacier retreat.

Post-earthquake Sedimentation Changed the Morphology of the Brahmaputra River

Post-earthquake Sedimentation Changed the Morphology of the Brahmaputra River

Holocene landscape evolution of the Brahmaputra River valley in the upper Assam Basin (India): Deduced from the soil-geomorphic studies

The Brahmaputra River basin exhibits a variety of landforms, including alluvial fans, old and active floodplains, and piedmont belts. The surface expression of the subsurface basement ridge, known as the Brahmaputra Arc, is characterized by paleosol exposures aligned along its crestal region. Using Optically Stimulated Luminescence (OSL) chronology and paleopedological studies, four stages of landform development have been identified in this region, influenced by neotectonics and climate change. The soils in the study area have been categorized into four members of the Quaternary Brahmaputra Morphostratigraphic Sequence (QBMS). QBMS-I (<1.77 ka) represents the youngest soil found in the active floodplains, QBMS-II (2–3.65 ka) includes the Mikri hills piedmont and adjacent river plains, QBMS-III (4–6.5 ka) covers most parts of the study area and is formed on alluvium. The oldest unit QBMS-IV (>7 ka) is exposed on the crest of the Brahmaputra Arc. These soils provide insights into the geomorphologic history of the region, with QBMS-II and III recording multiple avulsions during the Holocene. Micromorphological studies indicate that these soils have undergone multi-phase development under varying redox conditions. The Mid-Miocene compression in the foreland basin led to the formation of the Brahmaputra Arch, and subsequent sedimentation covered the crestal part. Presently, erosion and removal of sediment from the crestal region have exposed older soils as paleosols. Two alluvial fans occur in the study area, the older one located in the central part and the younger one in the northeast corner. The Naga hill piedmonts also exhibit a similar distribution, with the older segment in the central part and younger segments in the northern and southern parts. These patterns of piedmonts and alluvial fans suggest distinct tectonic episodes responsible for sediment redistribution in the study area. The proximity of the Brahmaputra Arc and the Naga thrust in the central part further supports this observation. The findings of this study are consistent with the episodes of neotectonic activity in the nearby Ganga plain, highlighting their regional relevance. Overall, the study provides valuable insights into the evolution of landforms in the Brahmaputra River basin, highlighting the role of neotectonics and climate change in shaping the landscape.

Assessing the spatial spread–skill of ensemble flood maps with remote-sensing observations

Abstract. An ensemble of forecast flood inundation maps has the potential to represent the uncertainty in the flood forecast and provide a location-specific likelihood of flooding. Ensemble flood map forecasts provide probabilistic information to flood forecasters, flood risk managers and insurers and will ultimately benefit people living in flood-prone areas. Spatial verification of the ensemble flood map forecast against remotely observed flooding is important to understand both the skill of the ensemble forecast and the uncertainty represented in the variation or spread of the individual ensemble-member flood maps. In atmospheric sciences, a scale-selective approach has been used to evaluate a convective precipitation ensemble forecast. This determines a skilful scale (agreement scale) of ensemble performance by locally computing a skill metric across a range of length scales. By extending this approach through a new application, we evaluate the spatial predictability and the spatial spread–skill of an ensemble flood forecast across a domain of interest. The spatial spread–skill method computes an agreement scale at every grid cell between each unique pair of ensemble flood maps (ensemble spatial spread) and between each ensemble flood map with a SAR-derived flood map (ensemble spatial skill; SAR: synthetic aperture radar). These two are compared to produce the final spatial spread–skill performance. These methods are applied to the August 2017 flood event on the Brahmaputra River in the Assam region of India. Both the spatial skill and spread–skill relationship vary with location and can be linked to the physical characteristics of the flooding event such as the location of heavy precipitation. During monitoring of flood inundation accuracy in operational forecasting systems, validation and mapping of the spatial spread–skill relationship would allow better quantification of forecast systematic biases and uncertainties. This would be particularly useful for ungauged catchments where forecast streamflows are uncalibrated and would enable targeted model improvements to be made across different parts of the forecast chain.

Receptor model-based source tracing and risk assessment of elements in sediment of a transboundary Himalayan River

This study utilized surface sediments from a potentially less polluted transboundary Himalayan River (Brahmaputra: China-India-Bangladesh) to investigate the abundance of 15 geochemically and ecologically significant elements and to predict their sources and ecological consequences. INAA was applied to determine the elemental concentrations. The average abundances (μg.g−1) of Rb (94.20), Cs (4.49), Th (20.31), & U (2.73) were 1.12–2.26 folds elevated than shale. Environmental indices disclosed a pollution status ranging from “uncontaminated to moderately contaminated,” with minimal Rb, U, and Th enrichment in the downstream zone. Consensus-based sediment quality guideline (SQG) threshold values suggested that only Cr (60% samples > TEL) may impose rare biological effects. Ecological risk indices suggested “minor to no” possible eco-toxicological risks for the accounted elements (Cr, Co, Mn, Zn, Sb, & As). The positive matrix factorization (PMF) model predicated the predominance of geogenic or crustal contributions (∼72.69%) for Al, K, Na, Ti, Co, Zn, Ba, Cs, As, Rb, Th, & U derived from elemental fractionations, mineral weathering, and bio-geo-chemical mobilization. The relative contributions of anthropogenic sources (∼27.31%; such as the construction of roads, settlement expansion, litter disposal, municipal waste discharge, mining activities, agricultural encroachment, etc.) on elemental distribution were significantly lower. The abundance of Cr and Mn was mainly influenced by anthropogenic sources. This study demonstrated the effectiveness of utilizing geo-environmental guidelines and receptor models in discriminating the natural & anthropogenic origins of metals in the complex riverine sediments of a less anthropogenically affected river.

Modeling the water-energy-food-environment nexus and transboundary cooperation opportunity in the Brahmaputra River Basin

Study regionThe Brahmaputra River Basin. Study focusThe Brahmaputra River Basin (BRB) is the most environmentally fragile and politically unstable transboundary river basin in South Asia. Therefore, incorporating the environmental sector into water-energy-food system analysis is necessary to better serve water resource management in the BRB. Integrated water resources system analysis can provide more perspectives for alleviating political tension and promoting cooperation in the basin. This study proposes a modeling framework to explore the water-energy-food-environment (WEFE) nexus and analyze transboundary cooperation opportunities in the BRB. Employing the framework, we attempt to answer three questions: (1) how can we understand the relationships between various sectors and coordinate their water demands? (2) How do these relationships influence riparian countries’ decisions? (3) What measures can promote the sustainable development of the BRB under climate change and water infrastructure development? New hydrological insights for the regionThe results show that the trade-off curve between economic benefits and environmental costs has declining marginal value in the BRB. When environmental constraints are raised, countries are more inclined to cooperate to obtain more economic benefits. Full cooperation in the BRB increases the economic benefits and prompts riparian countries to take a greener road among the shared socioeconomic pathways (SSP126). Water resource project construction can improve the utility of water resources in a country, thus enhancing its discourse power on benefit reallocation.