Managing hydrologic extremes using nature-based solutions in a snow-fed river basin of Nepal | |
| Author | Pradhan, Pragya |
| Call Number | AIT Diss no.WM-23-05 |
| Subject(s) | Climatic changes--Napal--Koshi River Basin Hydrological forecasting--Napal--Koshi River Basin |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering in Water Engineering and Management, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. WM-23-05 |
| Abstract | The Koshi River Basin is a transboundary river basin which experiences various hydrological extremes such as floods, flash floods, and droughts. These events have a significant effect on the economy, agriculture, and livelihoods of the region. However, the development of effective and efficient adaptation strategies to mitigate these hydrological extremes is challenging in the context of ongoing and increasing climatic stress. Therefore, this study aims to identify the hydrological extremes in the basin and assess the effectiveness of different Nature-Based Solutions (NBS) as adaptation strategies for their effective management. The study begins by projecting future climate (rainfall and maximum and minimum temperatures) to analyse their impact on hydrology, water availability, snowmelt, and hydrological extremes under Shared Socio-economic Pathways (SSPs) for three different future periods: near future (2015– 2045), mid future (2046–2075), and far future (2076–2100). The results indicate that all three regions of the basin (Low-lying Plain Areas, Middle Mountains, and High Himalayas) are likely to experience increases in rainfall and maximum and minimum temperatures in the future, resulting in decreased discharge in the near future period (2015–2045). The Soil and Water Assessment Tool (SWAT) is used to assess the impact of climate change on discharge, predicting a decrease in future discharge of 15– 20% in the Middle Mountains and High Himalayas during the near future period, and this figure is expected to increase by more than 50% in the far future (2076–2100). These analyses indicate that the basin will experience floods and flash floods in the future. Finally, the study provides different NBS as adaptation strategies to address the hydrological extremes caused by climate change. The research reveals that implementing NBS could decrease flood inundation by over 20% in urban and cropland regions. The findings of the study can be beneficial to early career researchers, policymakers, stakeholders, and local communities in identifying current strengths, shortcomings, and areas for improvement in hydrological extreme management before and after the occurrence of such events. The appropriate measures for reducing the impact of such hydrological extremes can assist in improving the livelihoods of the local inhabitants amidst the ongoing climate change in the Koshi River Basin of Nepal. |
| Year | 2023 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. WM-23-05 |
| Type | Dissertation |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shrestha, Sangam; |
| Examination Committee(s) | Sundaram, S. Mohana;Virdis, Salvatore; |
| Scholarship Donor(s) | Groundwater-Asia & CC-Thailand/ADB projects;Asian Institute of Technology Fellowship; |
| Degree | Thesis (Ph. D.) - Asian Institute of Technology, 2023 |