Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River
<p>The construction of the Akosombo and Kpong dams in the Lower Volta River basin in Ghana changed the downstream riverine ecosystem and affected the lives of downstream communities, particularly those who lost their traditional livelihoods. In contrast to the costs borne by those in the vicin...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2023-05-01
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| Series: | Hydrology and Earth System Sciences |
| Online Access: | https://hess.copernicus.org/articles/27/2001/2023/hess-27-2001-2023.pdf |
| _version_ | 1797819749206327296 |
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| author | A. Owusu A. Owusu J. Zatarain Salazar M. Mul P. van der Zaag P. van der Zaag J. Slinger J. Slinger |
| author_facet | A. Owusu A. Owusu J. Zatarain Salazar M. Mul P. van der Zaag P. van der Zaag J. Slinger J. Slinger |
| author_sort | A. Owusu |
| collection | DOAJ |
| description | <p>The construction of the Akosombo and Kpong dams in the Lower Volta River basin in Ghana changed the downstream riverine ecosystem and affected the
lives of downstream communities, particularly those who lost their
traditional livelihoods. In contrast to the costs borne by those in the
vicinity of the river, Ghana has enjoyed vast economic benefits from the
affordable hydropower, irrigation schemes and lake tourism that developed
after construction of the dams. Herein lies the challenge; there exists a
trade-off between water for river ecosystems and related services on the one hand and anthropogenic water demands such as hydropower or irrigation on the other. In this study, an Evolutionary Multi-Objective Direct Policy
Search (EMODPS) is used to explore the multi-sectoral trade-offs that exist
in the Lower Volta River basin. Three environmental flows, previously
determined for the Lower Volta, are incorporated separately as environmental objectives. The results highlight the dominance of hydropower production in the Lower Volta but show that there is room for providing environmental flows under current climatic and water use conditions if the firm energy requirement from Akosombo Dam reduces by 12 % to 38 % depending on the environmental flow regime that is implemented. There is uncertainty in climate change effects on runoff in this region; however multiple scenarios are investigated. It is found that climate change leading to increased annual inflows to the Akosombo Dam reduces the trade-off between hydropower and the environment as this scenario makes more water available for users. Furthermore, climate change resulting in decreased annual inflows provides the opportunity to strategically provide dry-season environmental flows, that is, reduce flows sufficiently to meet low flow requirements for key ecosystem services such as the clam fishery. This study not only highlights the challenges in balancing anthropogenic water demands and environmental considerations in managing existing dams but also identifies opportunities for compromise in the Lower Volta River.</p> |
| first_indexed | 2024-03-13T09:28:10Z |
| format | Article |
| id | doaj.art-62e56925d66b4fe1a729203bdb0f13eb |
| institution | Directory Open Access Journal |
| issn | 1027-5606 1607-7938 |
| language | English |
| last_indexed | 2024-03-13T09:28:10Z |
| publishDate | 2023-05-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Hydrology and Earth System Sciences |
| spelling | doaj.art-62e56925d66b4fe1a729203bdb0f13eb2023-05-26T06:27:08ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382023-05-01272001201710.5194/hess-27-2001-2023Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta RiverA. Owusu0A. Owusu1J. Zatarain Salazar2M. Mul3P. van der Zaag4P. van der Zaag5J. Slinger6J. Slinger7Land and Water Management Department, IHE Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the NetherlandsFaculty of Technology, Policy and Management, TU Delft, Jaffalaan 5, 2628 BX Delft, the NetherlandsFaculty of Technology, Policy and Management, TU Delft, Jaffalaan 5, 2628 BX Delft, the NetherlandsLand and Water Management Department, IHE Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the NetherlandsLand and Water Management Department, IHE Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the NetherlandsFaculty of Civil Engineering and Geosciences, TU Delft, Stevinweg 1, 2628 CN Delft, the NetherlandsFaculty of Technology, Policy and Management, TU Delft, Jaffalaan 5, 2628 BX Delft, the NetherlandsInstitute of Water Research, Rhodes University, Drosty Rd, Grahamstown, 6139, South Africa<p>The construction of the Akosombo and Kpong dams in the Lower Volta River basin in Ghana changed the downstream riverine ecosystem and affected the lives of downstream communities, particularly those who lost their traditional livelihoods. In contrast to the costs borne by those in the vicinity of the river, Ghana has enjoyed vast economic benefits from the affordable hydropower, irrigation schemes and lake tourism that developed after construction of the dams. Herein lies the challenge; there exists a trade-off between water for river ecosystems and related services on the one hand and anthropogenic water demands such as hydropower or irrigation on the other. In this study, an Evolutionary Multi-Objective Direct Policy Search (EMODPS) is used to explore the multi-sectoral trade-offs that exist in the Lower Volta River basin. Three environmental flows, previously determined for the Lower Volta, are incorporated separately as environmental objectives. The results highlight the dominance of hydropower production in the Lower Volta but show that there is room for providing environmental flows under current climatic and water use conditions if the firm energy requirement from Akosombo Dam reduces by 12 % to 38 % depending on the environmental flow regime that is implemented. There is uncertainty in climate change effects on runoff in this region; however multiple scenarios are investigated. It is found that climate change leading to increased annual inflows to the Akosombo Dam reduces the trade-off between hydropower and the environment as this scenario makes more water available for users. Furthermore, climate change resulting in decreased annual inflows provides the opportunity to strategically provide dry-season environmental flows, that is, reduce flows sufficiently to meet low flow requirements for key ecosystem services such as the clam fishery. This study not only highlights the challenges in balancing anthropogenic water demands and environmental considerations in managing existing dams but also identifies opportunities for compromise in the Lower Volta River.</p>https://hess.copernicus.org/articles/27/2001/2023/hess-27-2001-2023.pdf |
| spellingShingle | A. Owusu A. Owusu J. Zatarain Salazar M. Mul P. van der Zaag P. van der Zaag J. Slinger J. Slinger Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River Hydrology and Earth System Sciences |
| title | Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River |
| title_full | Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River |
| title_fullStr | Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River |
| title_full_unstemmed | Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River |
| title_short | Quantifying the trade-offs in re-operating dams for the environment in the Lower Volta River |
| title_sort | quantifying the trade offs in re operating dams for the environment in the lower volta river |
| url | https://hess.copernicus.org/articles/27/2001/2023/hess-27-2001-2023.pdf |
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