Development of seasonal flow outlook model for Ganges-Brahmaputra Basins in Bangladesh

Abstract. Bangladesh is crisscrossed by the branches and tributaries of three main river systems, the Ganges, Bramaputra and Meghna (GBM). The temporal variation of water availability of those rivers has an impact on the different water usages such as irrigation, urban water supply, hydropower generation, navigation etc. Thus, seasonal flow outlook can play important role in various aspects of water management. The Flood Forecasting and Warning Center (FFWC) in Bangladesh provides short term and medium term flood forecast, and there is a wide demand from end-users about seasonal flow outlook for agricultural purposes. The objective of this study is to develop a seasonal flow outlook model in Bangladesh based on rainfall forecast. It uses European Centre for Medium-Range Weather Forecasts (ECMWF) seasonal precipitation, temperature forecast to simulate HYDROMAD hydrological model. Present study is limited for Ganges and Brahmaputra River Basins. ARIMA correction is applied to correct the model error. The performance of the model is evaluated using coefficient of determination (R2) and Nash–Sutcliffe Efficiency (NSE). The model result shows good performance with R2 value of 0.78 and NSE of 0.61 for the Brahmaputra River Basin, and R2 value of 0.72 and NSE of 0.59 for the Ganges River Basin for the period of May to July 2015. The result of the study indicates strong potential to make seasonal outlook to be operationalized.

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INCOSE Practitioners Challenge 2019: Clean Water and Sanitation in the Ganges River Basin

Insight ◽

10.1002/inst.12256 ◽

2019 ◽

Vol 22 (3) ◽

pp. 28-33 ◽

Cited By ~ 1

Author(s):

Omar El‐Haloush ◽

Stephen Powley ◽

Yash Kaushik ◽

David Flanigan ◽

Joseph Sitomer

Keyword(s):

River Basin ◽

Clean Water ◽

Ganges River ◽

Water And Sanitation ◽

The Ganges ◽

Ganges River Basin

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Characterization of artisanal fisheries in Nepal and potential implications for the conservation and management of Ganges River Dolphin (Platanista gangetica gangetica)

10.7287/peerj.preprints.1197 ◽

2015 ◽

Author(s):

Shambhu Paudel ◽

Juan C Levesque ◽

Camilo Saavedra ◽

Cristina Pita ◽

Prabhat Pal

Keyword(s):

Anthropogenic Activities ◽

Fishing Effort ◽

Main Channel ◽

Artisanal Fisheries ◽

Ganges River ◽

River Systems ◽

River Dolphin ◽

Main River ◽

Local Species ◽

The Ganges

The Ganges River dolphin (Platanista gangetica gangetica) (GRD) is classified as one of the most endangered of all cetaceans in the world and the second scarcest freshwater cetacean. The population is estimated to be less than 2,000 individuals. In Nepal’s Narayani, Sapta Koshi, and Karnali river systems, survival of GRD continues to be threatened by various anthropogenic activities, such as dam construction and interactions with artisanal fisheries. A basic description of the geographic scope, economics, and types of gear used in these fisheries would help managers understand the fishery-dolphin interaction conflict and assist with developing potential solutions to reduce interactions between GRD and local fisheries in Nepal. The main purpose of the study was to collect fishery and socio-economic information by conducting interviews with local fishermen in the Narayani, Sapta Koshi, and Karnali river systems. Based on interviews (n = 163), 79 percent of Nepalese fishermen indicated fishing for local species (e.g., mullet [Rhinomugil corsula] or siloroid catfish [Bagarius bagarius]) was their primary form of income. Fishermen reported fishing effort was greater in summer than winter; greatest in the afternoon (1430 hrs ± 0.27) and during low water level conditions; and gear was set 4.8 ± 0.2 days/week. Fishermen reported using eight different types of monofilament nets (gillnets and cast nets). Sixty percent used gillnets less than 10 m long, and less than one third preferred gillnets between 10 and 100 m long; a few used gillnets longer than 100 m. Fishermen usually set their gear close to their village, and about 50 percent preferred to fish in tributaries followed by the main channel behind sandbars and islands, and the main channel near a bank. Fishermen reported seeing more GRD in the main river stem in winter. In summer, fishermen spotted more GRD in tributaries. Most fishermen told us they believed education, awareness, and changing occupations were important for GRD conservation, but they indicated that occupational options were currently limited in Nepal. Nepalese fishermen acknowledged that fisheries posed a risk to GRD, but they believed water pollution, and dam/irrigation development were the greatest threats.

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A framework to understand gender and structural vulnerability to climate change in the Ganges River Basin: lessons from Bangladesh, India and Nepal

10.5337/2014.230 ◽

2014 ◽

Cited By ~ 3

Author(s):

F. Sugden ◽

S. de Silva ◽

F. Clement ◽

N. Maskey-Amatya ◽

V. Ramesh ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Structural Vulnerability ◽

Ganges River ◽

Vulnerability To Climate Change ◽

The Ganges ◽

Ganges River Basin

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Hydro-geochemical evaluation of groundwater for irrigation in the Ganges river basin areas of Bangladesh

10.21203/rs.3.rs-161359/v1 ◽

2021 ◽

Author(s):

Md Shajedul Islam ◽

Md. Golam Mostafa

Keyword(s):

Water Quality ◽

River Basin ◽

Irrigation Water ◽

Anthropogenic Sources ◽

Total Hardness ◽

Water Type ◽

Irrigation Water Quality ◽

Ganges River ◽

The Ganges ◽

Ganges River Basin

Abstract Groundwater is a vital source of irrigation water, and it provides over 80% of the irrigated water supply in Bangladesh. The study aimed to assess the status of irrigation water of the Ganges river basin areas in the middle-west part of Bangladesh through the hydrogeochemical characterization and classification of groundwater. The study parameters were pH, EC, TDS, Ca2+, Mg2+, total hardness, Na+, K+, B, Cl−, HCO3 −, SO 42−, NO3 −, and PO43− along with irrigation water quality index (IWQindex), Na%, soluble sodium percentage, sodium adsorption ratio, residual sodium bicarbonate, magnesium adsorption ratio, permeability index, and Kelley’s ratio. The results showed that most of the water samples were acidic in the pre-monsoon and alkaline in the post-monsoon seasons, and the water type was Ca-HCO3. The significant geochemical process in the area determined was calcite and dolomite mineral dissolution, and there was no active cation exchange, and silicate weathering occurred. The statistical analyses showed that both the geogenic and anthropogenic sources were controlling the chemistry of the groundwater aquifers. Concerning irrigation water quality, the results revealed that all the quality parameters and IWQindex (32.04 to 45.39) were within the safety ranges, except for the EC and total hardness. The study results would be useful for future groundwater monitoring and management of the Ganges basin areas of Bangladesh part.

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Reviving the Ganges Water Machine: why?

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-12-8727-2015 ◽

2015 ◽

Vol 12 (9) ◽

pp. 8727-8759 ◽

Cited By ~ 3

Author(s):

U. A. Amarasinghe ◽

L. Mutuwatte ◽

L. Surinaidu ◽

S. Anand ◽

S. K. Jain

Keyword(s):

Water Supply ◽

River Basin ◽

Water Use ◽

Water Demand ◽

Monsoon Season ◽

Subsurface Water ◽

Ganges River ◽

Hot Weather ◽

The Ganges ◽

Ganges River Basin

Abstract. The Ganges River Basin may have a major pending water crisis. Although the basin has abundant surface water and groundwater resources, the seasonal monsoon causes a mismatch between supply and demand as well as flooding. Water availability and flood potential is high during the 3–4 months of the monsoon season. Yet, the highest demands occur during the 8–9 months of the non-monsoon period. Addressing this mismatch requires substantial additional storage for both flood reduction and improvements in water supply. Due to hydrogeological, environmental, and social constraints, expansion of surface storage in the Ganges River Basin is problematic. A range of interventions that focus more on the use of subsurface storage (SSS), and on the acceleration of surface–subsurface water exchange, have long been known as the "Ganges Water Machine". One approach for providing such SSS is through additional pumping prior to the onset of the monsoon season. An important necessary condition for creating such SSS is the degree of unmet water demand. This paper highlights that an unmet water demand ranging from 59 to 119 Bm3 exists under two different irrigation water use scenarios: (i) to increase Rabi and hot weather season irrigation to the entire irrigable area, and (ii) to provide Rabi and hot weather season irrigation to the entire cropped area. This paper shows that SSS can enhance water supply, and provide benefits for irrigation and other water use sectors. In addition, it can buffer the inherent variability in water supply and mitigate extreme flooding, especially in the downstream parts of the basin. It can also increase river flow during low-flow months via baseflow or enable the re-allocation of irrigation canal water. Importantly, SSS can mitigate the negative effects of both flooding and water scarcity in the same year, which often affects the most vulnerable segments of society – women and children, the poor and other disadvantaged social groups.

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Stable Strontium Isotopic Compositions of River Water, Groundwater and Sediments From the Ganges–Brahmaputra–Meghna River System in Bangladesh

Frontiers in Earth Science ◽

10.3389/feart.2021.592062 ◽

2021 ◽

Vol 9 ◽

Author(s):

Toshihiro Yoshimura ◽

Shigeyuki Wakaki ◽

Hodaka Kawahata ◽

H. M. Zakir Hossain ◽

Takuya Manaka ◽

...

Keyword(s):

River Water ◽

Chemical Weathering ◽

Drainage Basin ◽

Dissolution Kinetics ◽

River System ◽

Ganges River ◽

Brahmaputra River ◽

Terrestrial Water ◽

Stable Strontium ◽

The Ganges

The Sr isotopic composition of rivers and groundwaters in the Bengal Plain is a major contributor to the global oceanic Sr inventory. The stable strontium isotope ratios (δ88Sr) provide a new tool to identify chemical weathering reactions in terrestrial water. In this study, we investigated the spatiotemporal variations of δ88Sr in samples of river water, bedload sediment, and groundwater collected from the Ganges–Brahmaputra–Meghna drainage basin in Bangladesh, which is known to strongly influence the 87Sr/86Sr ratio in seawater. The average δ88Sr values of waters of the Ganges, Brahmaputra, and Meghna rivers were 0.269, 0.316, and 0.278‰, respectively. Our data showed little difference between seasons of high and low discharge. The δ88Sr values measured in sequential leaching fractions of sediments varied from –0.258 to 0.516‰ and were highest in the silicate fraction, followed in turn by the carbonate fraction and the exchangeable fraction. Both 87Sr/86Sr and δ88Sr of these waters are primarily controlled by the inputs of Sr in weathering products from the Bengal Plain and Sr from the Himalayan rivers (Ganges and Brahmaputra). Values of δ88Sr and Sr/Ca were higher in the Brahmaputra River than in the Ganges River, a difference we attribute to greater input from silicate weathering. The variations of δ88Sr and 87Sr/86Sr were greater in groundwater than in river waters. Mineral sorting effects and dissolution kinetics can account for the large scatter in 87Sr/86Sr and δ88Sr values. The depth profile of δ88Sr showed wide variation at shallow depths and convergence to a narrow range of about 0.31‰ at depths greater than 70 m, which reflects more complete equilibration of chemical interactions between groundwater and ambient sediments owing to the longer residence time of deeper groundwater. We found that δ88Sr values in the groundwater of Bangladesh were almost identical to those of river water from the lower Meghna River downstream of its confluence with the Ganges–Brahmaputra river system, thus confirming that the δ88Sr composition of the groundwater discharge to the Bay of Bengal is very similar to that of the river discharge.

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