Assessment of long-term hydrogeological changes and plausible solutions to manage hydrological extremes in the transnational Ganga river basin

L. Surinaidu,Upali Amarasinghe,M. J. Nandan,R. Maheswaran

doi:10.2166/h2oj.2020.049

Abstract

AbstractThe Ganga is an international transboundary river that flows across three major riparian countries: India, Nepal, and Bangladesh, where India shares a significant proportion of the total basin area. The river system is highly dynamic and regularly floods in all three countries due to abundant rainfall in a short period of only four months each year that causes tremendous loss of both property and human life. In this study, we have done a synoptic review to synthesize the hydrology, hydrogeology, and modeling studies that have analyzed hydrological changes and their impacts in the Ganga basin. This review also identifies some of the knowledge gaps and discusses possible options for enhancing the understanding of sustainable water development and management. This review indicated that transparent data sharing, use of satellite-based observations along with in-situ data, integrated hydro-economic modeling linked to reliable coupled surface–groundwater models, a central shared decision support center for early warning systems to deal with hydrological extremes, joint river commissions and monitoring teams, and multilateral water sharing treaties (agreements) are required to promote sustainable and equitable distribution of water resources and to avoid water sharing conflicts in the Ganga basin.

Highlights

The Ganga river flows across three major south South Asian countries: Nepal, India, and Bangladesh, and supports the livelihoods of more than 600 million people (Sharma et al 2010; Amarasinghe et al 2016a)
Gandak, and Yamuna indicated water availability would increase by 13%, 33, 21, and 28%, respectively, in these four sub-basins by the year 2050 when compared to the year 2010 under the greenhouse gas Representative Concentration Pathway (RCP) scenario 4.5
A recent study by Dutta et al (2020) on the Ganga river indicated that river quality has improved in terms of increased dissolved oxygen (DO) and reduced biological oxygen demand (BOD), fecal coliform, total coliform, and nitrate (NO3- ) concentrations following the nationwide lockdown due to the COVID-19 pandemic coupled with increased rainfall in 2020 of about 60% greater than average

Summary

Introduction

The Ganga river flows across three major south South Asian countries: Nepal, India, and Bangladesh, and supports the livelihoods of more than 600 million people (Sharma et al 2010; Amarasinghe et al 2016a). Any change in river flows/abstractions compromises the integrity of broader ecosystem functions (Richter & Thomas 2007), leading to tremendous pressure on basin water resources (Sharma et al 2010)

Methods

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Discussion

Conclusion