Dam Siltation in the Mediterranean Region Under Climate Change : A Case Study of Ahmed El Hansali Dam, Morocco
Mosaid, Hassan ; Barakat, Ahmed ; Bouras, El Houssaine LU
; Ismaili, Maryem
; El Garnaoui, Mohamed
; Abdelrahman, Kamal
and Kahal, Ali Y.
(2024)
In Water (Switzerland)
16(21).
- Abstract
Dams are vital for irrigation, power generation, and domestic water needs, but siltation poses a significant challenge, especially in areas prone to water erosion, potentially shortening a dam’s lifespan. The Ahmed El Hansali Dam in Morocco faces heightened siltation due to its upstream region being susceptible to erosion-prone rocks and high runoff. This study estimates the siltation at the dam from its construction up to 2014 using bathymetric data and the Brown model, which is a widely-used empirical model that calculates reservoir trap efficiency. Additionally, the study evaluates the impact of Land Use and Land Cover (LULC) changes and projected future rainfall until around 2076 based on siltation rates. The results indicate that... (More)
Dams are vital for irrigation, power generation, and domestic water needs, but siltation poses a significant challenge, especially in areas prone to water erosion, potentially shortening a dam’s lifespan. The Ahmed El Hansali Dam in Morocco faces heightened siltation due to its upstream region being susceptible to erosion-prone rocks and high runoff. This study estimates the siltation at the dam from its construction up to 2014 using bathymetric data and the Brown model, which is a widely-used empirical model that calculates reservoir trap efficiency. Additionally, the study evaluates the impact of Land Use and Land Cover (LULC) changes and projected future rainfall until around 2076 based on siltation rates. The results indicate that changes in LULC, particularly temporal variations in precipitation, have a significant impact on the siltation of the Ahmed El Hansali dam. Notably, rainfall is strongly correlated with the siltation rate, with an R2 of 0.92. The efficiency of sediment trapping (TE) is 97.64%, meaning that 97.64% of the sediment in the catchment area is trapped or deposited at the bottom of the dam. The estimated annual specific sediment yield is about 32,345.79 tons/km2/yr, and the sediment accumulation rate is approximately 4.75 Mm3/yr. The dam’s half-life is estimated to be around 2076, but future precipitation projections may extend this timeframe due to the strong correlation between siltation and precipitation. Additionally, soil erosion driven by land management practices plays a crucial role in future siltation dynamics. Hence, this study offers a comprehensive assessment of the siltation dynamics at the Ahmed El Hansali dam, providing essential information on the long-term effects of erosion, land use changes, and climate projections. These findings may assist decision makers in managing dam reservoir sedimentation more effectively, ensuring the durability of the dam and extending the reservoir life.
(Less)
- author
- Mosaid, Hassan
; Barakat, Ahmed
; Bouras, El Houssaine
LU
; Ismaili, Maryem
; El Garnaoui, Mohamed
; Abdelrahman, Kamal
and Kahal, Ali Y.
- organization
- publishing date
- 2024-11
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Ahmed El Hansali dam, bathymetric data, Brown model, climate change, LULC change, siltation analysis
- in
- Water (Switzerland)
- volume
- 16
- issue
- 21
- article number
- 3108
- publisher
- MDPI AG
- external identifiers
-
- scopus:85208599435
- ISSN
- 2073-4441
- DOI
- 10.3390/w16213108
- language
- English
- LU publication?
- yes
- id
- 4e7c05fd-5bbe-4e47-8732-daaabf4c8c9a
- date added to LUP
- 2025-01-15 11:29:34
- date last changed
- 2025-04-04 14:35:41
@article{4e7c05fd-5bbe-4e47-8732-daaabf4c8c9a,
abstract = {{<p>Dams are vital for irrigation, power generation, and domestic water needs, but siltation poses a significant challenge, especially in areas prone to water erosion, potentially shortening a dam’s lifespan. The Ahmed El Hansali Dam in Morocco faces heightened siltation due to its upstream region being susceptible to erosion-prone rocks and high runoff. This study estimates the siltation at the dam from its construction up to 2014 using bathymetric data and the Brown model, which is a widely-used empirical model that calculates reservoir trap efficiency. Additionally, the study evaluates the impact of Land Use and Land Cover (LULC) changes and projected future rainfall until around 2076 based on siltation rates. The results indicate that changes in LULC, particularly temporal variations in precipitation, have a significant impact on the siltation of the Ahmed El Hansali dam. Notably, rainfall is strongly correlated with the siltation rate, with an R<sup>2</sup> of 0.92. The efficiency of sediment trapping (TE) is 97.64%, meaning that 97.64% of the sediment in the catchment area is trapped or deposited at the bottom of the dam. The estimated annual specific sediment yield is about 32,345.79 tons/km<sup>2</sup>/yr, and the sediment accumulation rate is approximately 4.75 Mm<sup>3</sup>/yr. The dam’s half-life is estimated to be around 2076, but future precipitation projections may extend this timeframe due to the strong correlation between siltation and precipitation. Additionally, soil erosion driven by land management practices plays a crucial role in future siltation dynamics. Hence, this study offers a comprehensive assessment of the siltation dynamics at the Ahmed El Hansali dam, providing essential information on the long-term effects of erosion, land use changes, and climate projections. These findings may assist decision makers in managing dam reservoir sedimentation more effectively, ensuring the durability of the dam and extending the reservoir life.</p>}},
author = {{Mosaid, Hassan and Barakat, Ahmed and Bouras, El Houssaine and Ismaili, Maryem and El Garnaoui, Mohamed and Abdelrahman, Kamal and Kahal, Ali Y.}},
issn = {{2073-4441}},
keywords = {{Ahmed El Hansali dam; bathymetric data; Brown model; climate change; LULC change; siltation analysis}},
language = {{eng}},
number = {{21}},
publisher = {{MDPI AG}},
series = {{Water (Switzerland)}},
title = {{Dam Siltation in the Mediterranean Region Under Climate Change : A Case Study of Ahmed El Hansali Dam, Morocco}},
url = {{http://dx.doi.org/10.3390/w16213108}},
doi = {{10.3390/w16213108}},
volume = {{16}},
year = {{2024}},
}