West African Coast Struggling with Coastal Erosion
Deltares is working on the quantification of the large-scale coastal sediment budget of four countries in West Africa: Ivory Coast, Ghana, Togo and Benin.
The main objective of the study is to quantify natural sediment transport patterns and the potential effects of major human interventions and climate change on the sediment budget and consequent shoreline changes.
According to the Deltares project leader Alessio Giardino, the study is unique for a number of reasons. “First of all, the quantification of the large sediment budget, with one consistent set of numerical models, will make it possible to overcome the fragmentation of information between different countries.”
“This large-scale study will also allow for the assessment of the implications of action in one country for neighboring countries. Finally, sharing information and creating awareness are key to the success of a project of this kind and so the main output from the project will be shared in a number of consultation and validation workshops,” added Giardino.
The coast of West Africa consists of a narrow low-lying coastal strip maintained by sediment from rivers that is transported along the coast by waves and currents like a “sand river”.
The coastal areas are home to 31% of the region’s population — which is growing at a rate of four percent annually. The coast also accounts for 56% of the region’s GDP.
Today, however, much of the fluvial sand flow is blocked by river dams and/or interrupted at several locations by harbor jetties. The sandy coastal barrier is therefore eroding almost everywhere; the situation is already critical and it is likely to degenerate in the future due to climate change.