Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir
Sustainable water resources of reservoirs depend on preserving the valuable storage capacity. Sediment management is a crucial task in reservoir operations. Extreme floods caused by typhoon events have brought a massive amount of sediments from the watershed of Shihmen Reservoir in Taiwan. In the ca...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-02-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/14/3/479 |
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| author | Fong-Zuo Lee Jihn-Sung Lai Tetsuya Sumi |
| author_facet | Fong-Zuo Lee Jihn-Sung Lai Tetsuya Sumi |
| author_sort | Fong-Zuo Lee |
| collection | DOAJ |
| description | Sustainable water resources of reservoirs depend on preserving the valuable storage capacity. Sediment management is a crucial task in reservoir operations. Extreme floods caused by typhoon events have brought a massive amount of sediments from the watershed of Shihmen Reservoir in Taiwan. In the case study of Shihmen Reservoir, the primary purpose of the sediment management strategies is to minimize sediment deposition and recover reservoir capacity. Two assessment indexes, the capacity–inflow ratio (CIR) and the capacity–sediment ratio (CSR) are investigated to provide a feasible assessment of desilting techniques. Three desilting projects have been planned and implemented in progress, including one modified power plant penstock and two desilting tunnels. Without effective sediment management strategies, the projected storage capacity may drop to 32.9% of the initial storage capacity in the next fifty years. On the other hand, if sediment management is implemented as per the project schedule, 70.3% of the initial storage capacity may be retained, enabling the provision of sustainable water supplies to meet projected water demands. In investigating the impacts caused by the desilting operations, the floodwater level and riverbed variations along the downstream river of the dam are simulated by the hydromorphological model. From simulated results, the downstream river morphology may adjust toward the equilibrium state under the long-term desilting operations of Shihmen Reservoir. Although relatively high sediment concentration is released during the desilting operation, it decays gradually along the downstream river. In addition, riverbed deposition does not significantly affect the floodwater level caused by the increment of riverbed elevation in desilting operations. |
| first_indexed | 2024-03-09T22:55:03Z |
| format | Article |
| id | doaj.art-5203b077564f4d709b838d0dde1dd19a |
| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-09T22:55:03Z |
| publishDate | 2022-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-5203b077564f4d709b838d0dde1dd19a2023-11-23T18:12:31ZengMDPI AGWater2073-44412022-02-0114347910.3390/w14030479Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen ReservoirFong-Zuo Lee0Jihn-Sung Lai1Tetsuya Sumi2Hydrotech Research Institute, National Taiwan University, Taipei 10617, TaiwanHydrotech Research Institute, National Taiwan University, Taipei 10617, TaiwanWater Resources Research Center, Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, Kyoto 611-0011, JapanSustainable water resources of reservoirs depend on preserving the valuable storage capacity. Sediment management is a crucial task in reservoir operations. Extreme floods caused by typhoon events have brought a massive amount of sediments from the watershed of Shihmen Reservoir in Taiwan. In the case study of Shihmen Reservoir, the primary purpose of the sediment management strategies is to minimize sediment deposition and recover reservoir capacity. Two assessment indexes, the capacity–inflow ratio (CIR) and the capacity–sediment ratio (CSR) are investigated to provide a feasible assessment of desilting techniques. Three desilting projects have been planned and implemented in progress, including one modified power plant penstock and two desilting tunnels. Without effective sediment management strategies, the projected storage capacity may drop to 32.9% of the initial storage capacity in the next fifty years. On the other hand, if sediment management is implemented as per the project schedule, 70.3% of the initial storage capacity may be retained, enabling the provision of sustainable water supplies to meet projected water demands. In investigating the impacts caused by the desilting operations, the floodwater level and riverbed variations along the downstream river of the dam are simulated by the hydromorphological model. From simulated results, the downstream river morphology may adjust toward the equilibrium state under the long-term desilting operations of Shihmen Reservoir. Although relatively high sediment concentration is released during the desilting operation, it decays gradually along the downstream river. In addition, riverbed deposition does not significantly affect the floodwater level caused by the increment of riverbed elevation in desilting operations.https://www.mdpi.com/2073-4441/14/3/479reservoirsediment managementextreme floodtyphoondesilting techniquesustainable water resources |
| spellingShingle | Fong-Zuo Lee Jihn-Sung Lai Tetsuya Sumi Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir Water reservoir sediment management extreme flood typhoon desilting technique sustainable water resources |
| title | Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir |
| title_full | Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir |
| title_fullStr | Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir |
| title_full_unstemmed | Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir |
| title_short | Reservoir Sediment Management and Downstream River Impacts for Sustainable Water Resources—Case Study of Shihmen Reservoir |
| title_sort | reservoir sediment management and downstream river impacts for sustainable water resources case study of shihmen reservoir |
| topic | reservoir sediment management extreme flood typhoon desilting technique sustainable water resources |
| url | https://www.mdpi.com/2073-4441/14/3/479 |
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