Hydrological responses of the Brahmaputra river basin using CMIP6 GCM projections for supporting climate resilient infrastructure design

ABSTRACT

The central northern region of Bangladesh has a low density and quality of sustainable rural infrastructures, and it is frequently affected by climate change-induced seasonal flooding and associated river erosion. This study used the Soil and Water Assessment Tool (SWAT) hydrological model to simulate future discharges under moderate and extreme Shared Socio-economic Pathway (SSP) scenarios, utilizing 13 bias-corrected Coupled Model Intercomparison Project Phase 6 (CMIP6) General Circulation Models (GCMs). Using these flow projections, the 1D HEC-RAS hydrodynamic model was then simulated to assess future water level fluctuations in six major rivers in the study region. The results indicate that the dry season will experience a more notable flow increase (up to 45%) than the wet season (up to 42%) compared to the baseline under the extreme scenario by 2100. The subsequent rises in water levels will also be significant in the major rivers in the Brahmaputra-Teesta River system. Based on these future water level changes, the study has prepared a guideline for building climate-resilient infrastructures in the study area.

KEYWORDS:

• Brahmaputra river basin
• climate change
• climate resilient infrastructure
• design water level changes
• future flow projections

Acknowledgments

The work has been supported by the research project entitled, ‘‘PROVATi3 (Promoting Resilience of Vulnerable through Access to Infrastructure, Improved Skills, and Information’ carried out by the Institute of Water and Flood Management (IWFM) of Bangladesh University of Engineering and Technology (BUET). This project is implemented by the Local Government Engineering Department (LGED) and sponsored by the International Fund for Agricultural Development (IFAD). The authors would like to acknowledge the access to observed water level, discharge, and bathymetric data from the Bangladesh Water Development Board (BWDB).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, ASI, upon reasonable request.

Additional information

Funding

The work was supported by the International Fund for Agricultural Development under PROVATi3 project of Local Government Engineering Department.

Notes on contributors

Faruque Abdullah

Faruque Abdullah is a Master’s student in the Department of Water Resources Engineering of Bangladesh University of Engineering and Technology (BUET). He graduated from the Department of Water Resources Engineering, BUET in 2017. He served as a Research Associate in the Climate Modelling and Simulation Lab of Institute of Water and Flood Management (IWFM), BUET from 2018 to 2022 and worked on numerous national and international research and consultancy projects focusing on regional climate modelling, climate change assessments, basin-scale hydrological modelling, river hydrodynamic modelling, urban drainage design and flood simulation, coastal and storm surge modelling, weather forecast modelling, GIS and satellite remote sensing etc. He represented BUET in the International Youth Scientific Conference (IYSC)-2019, Kathmandu, Nepal. He worked as a Visiting Scientist at the Potsdam Institute for Climate Impact Research (PIK), Germany from October, 2019 to December, 2019 and worked with PIK’s Research Department 2- Climate Resilience. After Returning to Bangladesh, he continued working with PIK as a Guest Researcher from 2020 to 2022 on various research collaborations such as assessing future climate change impacts on flood in the GBM basin, Evolution of global climate models (CMIP3 to CMIP6) in capturing climate variability of South Asia etc. In his Masters thesis, he is currently working on developing an integrated monitoring system of water level, flood, shoreline and floodplain bathymetry of Jamuna River from multi-satellite data. Moreover, he is currently working as an Assistant Engineer at PGCL of Bangladesh Oil, Gas and Mineral Corporation (Petrobangla) from 2022.

Wasif Bin Mamoon

Wasif Bin Mamoon is a PhD candidate in Environment and Water Resources specialisation at Marquette University in Milwaukee, WI. He received his BSc and MSc in Water Resources Engineering from Bangladesh University of Engineering and Technology, in 2019 and 2022, respectively. His current research focuses on analysing stream nutrient dynamics and modelling stream nutrients using dimension-reduction techniques. Before that, he was a Research Assistant at the Institute of Water and Flood Management, responsible for assessing the climate change impacts and applying hydrologic and hydraulic models at the watershed scale.

AKM Saiful Islam

AKM Saiful Islam is a Professor at the Institute of Water and Flood Management at the Bangladesh University of Engineering and Technology (BUET). He has received a Bachelor of Science in Civil Engineering (1989) from BUET, a Master of Science in Water Resources Engineering (1999) from BUET, and a Ph.D. in Civil Engineering (2004) from Drexel University, USA. His research interests aim at climate change impact on hydrology, water resources management, urban and coastal flood risk management, remote sensing applications for disaster risks reduction. His research adopted regional climate modelling, basin-scale hydrological modelling, river hydrodynamic modelling, urban flood modelling, coastal and storm surge modelling, weather forecast modelling, satellite remote sensing for environmental monitoring, hydroinformatics for disaster risks reduction and climate change adaptation. He has published over 70 peer-reviewed journal articles, more than 100 conference papers, and contributed to 9 book chapters. Over the past decade, Dr. Islam has led several major international scientific climate change assessments and the reports by the Intergovernmental Panel on Climate Change (IPCC). He contributed to the IPCC’s Fifth Assessment Report and IPCC Special Report on Global Warming of 1.5°C as an Expert Reviewer. He was a Lead Author on the IPCC’s Sixth Assessment Report (AR6) for Working Group I (WGI). He also currently serves as the Coordinator of the Climate Change Study Cell at IWFM, BUET.

GM Tarekul Islam

G M Tarekul Islam is a Professor at the Institute of Water and Flood Management (IWFM), Bangladesh University of Engineering and Technology (BUET). He graduated in Civil Engineering in 1994 and did his Master’s in Water Resources Engineering in 1996 from BUET. He received his PhD from the University of Tokyo in 2000. He was awarded the prestigious JSPS fellowship for post-doctoral research at Hiroshima University, Japan, from 2006 to 2008. He was a Visiting Professor at the Department of Disaster Risk Management and Sustainable Development of Bahir Dar University, Ethiopia, in 2011, where he immensely contributed to updating and developing new course curricula for introducing a Master’s program in Disaster Risk Reduction under the sponsorship of UNDP. He played a pivotal role in introducing the post-graduate academic program on humanitarian engineering at BUET. He was awarded by the University Grants Commission (UGC) of Bangladesh as the best researcher in the Engineering and Technology category in 2003. He has served on various committees of national and international organizations and has provided consultancy and advisory services to numerous projects for government and non-government entities. He has published over 150 papers in international journals and conference proceedings.

Sujit Kumar Bala

Sujit Kumar Bala is a professor (retired) at the Institute of Water and Flood Management (IWFM), Bangladesh University of Engineering and Technology (BUET). He did his Master’s in Irrigation Engineering in 1982 from Tashkent Institute of Irrigation and Mechanization of Agriculture, Uzbekistan, ex-USSR. He received his PhD from the same Institute in 1986 in the field of modernization of water application in cotton fields through modification of a sprinkler system. Since returning back to Bangladesh from ex-USSR in 1986, he was involved in various consultancy jobs in Bangladesh including the Jamuna Multipurpose Bridge Construction (River Training and Guide Bund), the Large Bridge and Culvert Project implemented by LGED from 1994 to 1997 in different upazilas of Bangladesh and many more. He joined the Institute of Water and Flood Management (IWFM), Bangladesh University of Engineering and Technology (BUET) in 1997. His field of interest was agricultural water management; hydrology; bridge informatics; gender, water and society; interdisciplinary research, etc. He was involved in many national and international research projects and has a good number of international journal publications, Book Chapters, etc. He has published over 100 papers in international journals and conference proceedings. He served as the Director of the IWFM from 2017 to 2019, At present, he is an Honorary Chairman of the Board of Members of Dhaka WASA.

Shadman Kaiser

Shadman Kaiser is an Associate Consultant at WSP USA. He earned a Master of Science in Civil and Environmental Engineering from the University of Utah, where he conducted research on water quality and treatment. His work, funded by the National Institutes of Health, focused on harmful cyanobacterial growth in Utah, Nevada, and California. Previously he completed his B.Sc. in Civil Engineering from Bangladesh University of Engineering and Technology (BUET) in 2019 and served as a Research Assistant at the Institute of Water and Flood Management (IWFM), BUET afterwards.

Khaled Mohammed

Khaled Mohammed works as a forecaster at the Hydrologic Forecast Centre (HFC) of the Province of Manitoba, Canada. He has a BSc in Civil Engineering from Ahsanullah University of Science and Technology (AUST), an MSc in Water Resources Development from Bangladesh University of Engineering and Technology (BUET), and is a PhD in Civil Engineering candidate at the Université de Sherbrooke (UdeS). His research interests include flood forecasting, machine learning, remote sensing and climate change.

Maruf Billah

Maruf Billah received his B.Sc. degree in Disaster Management from Patuakhali Science and Technology University, Patuakhali, Bangladesh, in 2017, and his M.Sc. degree in Water Resource Development from the Bangladesh University of Engineering and Technology (BUET), Dhaka, Bangladesh, in 2022. His professional expertise primarily encompasses remote sensing, water resource development, flood management, and environmental science. Previously Maruf worked as a GIS and Remote Sensing Specialist in the Climate Modeling and Simulation Laboratory at the Institute of Water and Flood Management (IWFM). Currently, he serves as an IT and GIS Specialist in the Khulna Water Supply Project Phase Two, an ADB-funded initiative. In addition, he is the Director and CEO of Verdantcore Research and Consultancy, a consulting firm dedicated to environmental and resource management solutions.

Mohan Kumar Das

Dr. Mohan Kumar Das, born in Cox’s Bazar, Bangladesh, is the Executive Director at the National Oceanographic and Maritime Institute (NOAMI) and an Adjunct Faculty member in the Department of Meteorology at the University of Dhaka. He has held key roles in institutions like the Bangladesh Meteorological Department, the SAARC Meteorological Research Centre, and the Regional Integrated Multi-Hazard Early Warning System in Bangkok. His post-doctoral research was conducted with the Institute of Water and Flood Management (IWFM) at BUET and the Potsdam Institute of Climate and Impact Research (PIK) in Germany. He has received the Ocean Science Best Trainee Award from UNESCO/IOC-ODC and the Best Presenter Award (Professionals Category) at the International Conference on Climate Change 2022 (ICCC 2022). Dr. Das has published extensively on ocean and climate extremes, hydro-meteorology, flash floods, rainfall, nor’westers/tornadoes, monsoons, climate change, and tropical cyclones. As a multidisciplinary researcher and practitioner, specializing in Physical Sciences, Numerical Modelling, Satellite Technology, Climate Science, Meteorological Hazards Risk Management, and Data Analytics, Dr. Das is the Associate Editor of the Journal of NOAMI and a founding member and Joint Secretary of the South Asian Meteorological Association (SAMA).