Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh

Coastal Bangladesh in the Ganges Delta is comprised of polders, which are unique hydrological boundaries that are crucial for the livelihoods of farmers and local dwellers. These polder systems are facing severe water scarcity for agricultural use in the dry season, and the shallow aquifer system is...

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Main Authors: Mizan, Syed Adil, Jampani, Mahesh, Rahman, Md. A., Hasib, Md. R., Sena, Dipaka Ranjan, Mondal, M. K., Alam, R., Matheswaran, Karthikeyan
Format: Abstract
Language:Inglés
Published: 2024
Subjects:
Online Access:https://hdl.handle.net/10568/168880
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author Mizan, Syed Adil
Jampani, Mahesh
Rahman, Md. A.
Hasib, Md. R.
Sena, Dipaka Ranjan
Mondal, M. K.
Alam, R.
Matheswaran, Karthikeyan
author_browse Alam, R.
Hasib, Md. R.
Jampani, Mahesh
Matheswaran, Karthikeyan
Mizan, Syed Adil
Mondal, M. K.
Rahman, Md. A.
Sena, Dipaka Ranjan
author_facet Mizan, Syed Adil
Jampani, Mahesh
Rahman, Md. A.
Hasib, Md. R.
Sena, Dipaka Ranjan
Mondal, M. K.
Alam, R.
Matheswaran, Karthikeyan
author_sort Mizan, Syed Adil
collection Repository of Agricultural Research Outputs (CGSpace)
description Coastal Bangladesh in the Ganges Delta is comprised of polders, which are unique hydrological boundaries that are crucial for the livelihoods of farmers and local dwellers. These polder systems are facing severe water scarcity for agricultural use in the dry season, and the shallow aquifer system is often saline because of sea level rise, tidal impacts, and incremental groundwater use during Rabi for irrigation. Integrated management options are needed for the polder systems to optimize the salinity conditions. In this context, a comprehensive groundwater flow and salinity transport model was developed for a polder near Khulna City in Bangladesh. Water and salinity dynamics were assessed to develop alternate polder management scenarios. The modeling framework involved coupling MODFLOW and SEAWAT models to evaluate salinity ingress to the aquifer due to tidal interactions and groundwater abstraction. The polder landscape in the Ganges delta system is aligned with a natural hydrological river boundary. The interplay between the polders and the surrounding river system is essential for maintaining the ecological balance of the delta. The controlled water levels within the polders support rice cultivation, aquaculture, and other agricultural activities, while the natural rainfall and tidal hydrology aid in replenishing the local aquifers. Aquifer parameters and geometry, water flows in the polder, climate, hydrology, and water quality data were collected from the field and also obtained from secondary sources. The model encompassed a detailed conceptualization of the polder aquifer system, including the dynamics of surface water-groundwater interactions with tidal intrusion induced salinity gradient. The calibrated model showed good agreement with observed or adopted and simulated groundwater levels within the polder. These findings highlight the significant influence of tidal dynamics in the peripheral rivers on seasonal variations in groundwater flow patterns and salinity dynamics. This model, with its robustness, can serve as a reliable tool for stakeholders and policymakers to design sustainable groundwater management strategies for the polder systems.
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spelling CGSpace1688802025-07-23T18:05:32Z Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh Mizan, Syed Adil Jampani, Mahesh Rahman, Md. A. Hasib, Md. R. Sena, Dipaka Ranjan Mondal, M. K. Alam, R. Matheswaran, Karthikeyan groundwater flow modelling salinity polders coastal areas Coastal Bangladesh in the Ganges Delta is comprised of polders, which are unique hydrological boundaries that are crucial for the livelihoods of farmers and local dwellers. These polder systems are facing severe water scarcity for agricultural use in the dry season, and the shallow aquifer system is often saline because of sea level rise, tidal impacts, and incremental groundwater use during Rabi for irrigation. Integrated management options are needed for the polder systems to optimize the salinity conditions. In this context, a comprehensive groundwater flow and salinity transport model was developed for a polder near Khulna City in Bangladesh. Water and salinity dynamics were assessed to develop alternate polder management scenarios. The modeling framework involved coupling MODFLOW and SEAWAT models to evaluate salinity ingress to the aquifer due to tidal interactions and groundwater abstraction. The polder landscape in the Ganges delta system is aligned with a natural hydrological river boundary. The interplay between the polders and the surrounding river system is essential for maintaining the ecological balance of the delta. The controlled water levels within the polders support rice cultivation, aquaculture, and other agricultural activities, while the natural rainfall and tidal hydrology aid in replenishing the local aquifers. Aquifer parameters and geometry, water flows in the polder, climate, hydrology, and water quality data were collected from the field and also obtained from secondary sources. The model encompassed a detailed conceptualization of the polder aquifer system, including the dynamics of surface water-groundwater interactions with tidal intrusion induced salinity gradient. The calibrated model showed good agreement with observed or adopted and simulated groundwater levels within the polder. These findings highlight the significant influence of tidal dynamics in the peripheral rivers on seasonal variations in groundwater flow patterns and salinity dynamics. This model, with its robustness, can serve as a reliable tool for stakeholders and policymakers to design sustainable groundwater management strategies for the polder systems. 2024-12-11 2025-01-12T05:44:59Z 2025-01-12T05:44:59Z Abstract https://hdl.handle.net/10568/168880 en Open Access Mizan, Syed Adil; Jampani, Mahesh; Rahman, Md. A.; Hasib, Md. R.; Sena, Dipaka Ranjan; Mondal, M. K.; Alam, R.; Matheswaran, Karthikeyan. 2024. Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh [Abstract only]. Paper presented at the American Geophysical Union Annual Meeting 2024 (AGU24) on What’s Next for Science, Washington, DC, USA, 9-13 December 2024. 1p.
spellingShingle groundwater flow
modelling
salinity
polders
coastal areas
Mizan, Syed Adil
Jampani, Mahesh
Rahman, Md. A.
Hasib, Md. R.
Sena, Dipaka Ranjan
Mondal, M. K.
Alam, R.
Matheswaran, Karthikeyan
Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title_full Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title_fullStr Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title_full_unstemmed Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title_short Modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal Bangladesh
title_sort modeling groundwater flow and salinity dynamics for developing polder management strategies in coastal bangladesh
topic groundwater flow
modelling
salinity
polders
coastal areas
url https://hdl.handle.net/10568/168880
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