The Beninese Ministry of Living Environment and Sustainable Development kicked off the coastal protection works near the coastal villages Avlékété and Djégbadji, part of the town called Ouidah. At the beginning of 2018, the Ministry awarded Jan De Nul Group for its in-house developed design of a submerged dike installed off the coast to protect the coastline against the impact of the Atlantic Ocean.
"During the past year, our engineers carried out the necessary studies and demonstrated, based on model tests, that this concept is sustainable and that it works. We are proud that we are able to realize our concept on this scale in Benin and hope to be able to help other vulnerable coastlines in Africa and elsewhere in the world, "says Filip Morobé, Area Director Africa at Jan De Nul Group.
The coast of Benin is highly susceptible to erosion due to its geographical situation along the Atlantic Ocean. The erosion of the beaches is further enhanced by the construction of paved dikes on land. Consequently, coastal tourism can not develop in this area. For that reason, the Government makes an extra effort in its Government Action Programme to protect the Beninese coast.
Today, the client, local politicians, Jan De Nul’s Group project team and other prominent people attended the first stone installation activities, executed by the side stone installation vessel Pompeï, near Avlékété.
Sustainable and submerged
Jan De Nul Group's design is a submerged dike at about 150 meters off the coast. The dike has a wave damping effect, which means that the waves of the Atlantic Ocean are broken before they reach the coast. A wave-free climate develops between the submerged dike and the coast. This will significantly reduce the impact on the beaches, as a result of which the sand will move less and the erosion will decrease.
Because the dike is submerged, the view of the horizon will not be disturbed. From the beginning, Jan De Nul Group has worked on maintaining that aesthetic character, which is very important in the context of the government plans to fully develop coastal tourism in Benin.
Stone installation and beach regeneration
The works started in February 2018. Granite rock from national and international quarries was transported to site.
The stone installation works were kicked off today in Avlékété. In a first phase, a submerged dike of 2 kilometres will be installed. Another two rock installation campaigns of 2 kilometres each will follow, one in Avlékété and another in Djégbadji.
After the installation of the submerged dikes, Trailing Suction Hopper Dredgers of Jan De Nul Group will dredge and reclaim sand to restore the affected beaches.
Works will be completed in 2021.
During the past year, our engineers carried out the necessary studies and demonstrated, based on model tests, that this concept is sustainable and that it works. We are proud that we are able to realize our concept on this scale in Benin and hope to be able to help other vulnerable coastlines in Africa and elsewhere in the world.