Senegalese island keeps coastal erosion at bay with stakes in sand

DIOGUE ISLAND, Senegal, July 25 (Reuters) – Simple wooden structures padded with coconut palm fronds are helping residents of Senegal’s southern Diogue Island reclaim stretches of sandy beach from sea swells. Atlantic that threaten much of the West African coast.

In some areas, half-submerged tree stumps and crumbling abandoned buildings show the impact of the waves – and the continued degradation of the coastline, where 56% of West Africa’s economic activity is generated and about a third of its population live, according to the World Bank.

“The ocean was so far away that you could hear it without seeing it,” says Angèle Diatta, head of the women’s association in the village of Diogue Diola, on the island at the mouth of the Casamance river, where the big tides sometimes sweep away the dwellings. .

West Africa has many of these low-lying deltas, making its coastal ecosystems among the most vulnerable to sea level rise, erosion, saltwater intrusion and flooding, the United Nations World Climate Group said in its latest report. Read more

On Diogue, a method of driving clusters of piles into the wet shore helps protect some of the island’s beaches. These areas have grown by about 30 meters (98 feet) since 2019, according to project organizers.

“Each time we gain ground, we can extend the structure, add more sticks, as they say little by little the bird makes its nest,” said Gilbert Bassene, a teacher at the local primary school, who helped to maintain the homemade defenses of the beach.

In early July, he and the initiative’s founder, Patrick Chevalier, used a red string and a marked stick to measure the amount of sand accumulated next to one of the structures and wove dry coconut branches to through its stakes to help trap more sediment.

These semi-permeable groynes are based on a model pioneered in Canada, where beaches were protected without accelerating sediment loss elsewhere, according to a 2002 analysis by scientists at the University of Quebec.

“With the little we have, we can do amazing work,” Bassene said on the palm-lined beach, where children had gathered to watch him work.

Nevertheless, better coastal management is needed at the regional level in West Africa, where “despite interventions, rates of coastal erosion in different countries continue to increase”, according to a 2020 study published in the Journal of Coastal Conservation.

Communities are already suffering from the fallout.

Coastal degradation cost Benin, Ivory Coast, Senegal and Togo a total of $3.8 billion in 2017, according to the World Bank, which is supporting an ongoing project to relocate 10,000 people of Saint-Louis, a city in the north of Senegal which extends on a thin peninsula between the Senegal River and the ocean.

Some people on Diogue think they face a similar fate. “It’s not easy to admit, but one day the village will have to move,” said village chief Cherif Diatta.

Editing by Alessandra Prentice; edited by Barbara Lewis

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