Fluvial sediment transport degradation after dam construction in North Africa

Recent reductions of sediment transport are observed in Bouregreg River and estuary close to the city of Rabat in Morocco. The cause of this evolution in sediment transport which may be due to human activities (dam, pollution), climate variability and natural events has been investigated from a paleo-hydrological approach. Sedimentological and geochemical analyses of slackwater flood deposits are used to assess the impact of a dam installed in 1974 and the climate change on the evolution of sediment transport during about 60 years. Higher accumulation rate of about 3,64 cm/year is observed between 1950 and 1978, whereas it was much lower about 0,41 cm/year between 1990 and 2017. This strong decrease in sediment rate appears much more due to the impact of dam construction rather than to climate change, however climate change in an increasing concern for the future.

Automated summary

Recent reductions in sediment transport in the Bouregreg River and estuary near the city of Rabat in Morocco have been attributed to a combination of human activities, climate variability, and natural events. Research indicates that the installation of a dam in 1974 has had a significant impact on sediment transport rates, with climate change also becoming a growing concern for the future.