EfficacitÃ© du rechargement de la plage de Pilote Bar (Saint-Louis) aprÃ¨s une dÃ©cennie d’Ã©rosion - Balde, Omar; Sakho, Issa; Diouf, Mouhamadoul Bachir; Bop, Mamadou; Tine, Djibril; Ibouroi, Wardou (European Scientific Journal, ESJ, 2021)
L’ouverture d’une brÃ¨che dans la bande de sable de la Langue de Barbarie Ã Saint Louis (SÃ©nÃ©gal) en 2004 a eu des consÃ©quences sur l’Ã©tendue du bief fleuve-mer du Gandiolais. En effet, les zones en face de la brÃ¨che deviennent trÃ¨s vulnÃ©rables Ã l’action des vagues dÃ©vastatrices de la Grande CÃ´te. La dÃ©cision d’une protection douce par envasement a Ã©tÃ© prix pour protÃ©ger le village de Pilote Bar des risques d’Ã©rosion et de submersion marine. Cette premiÃ¨re expÃ©rience au SÃ©nÃ©gal a eu des rÃ©sultats positifs. La recharge de la plage du Pilote Bar a favorisÃ© la formation d’un lagon. Une sÃ©dimentation et une augmentation de la hauteur des pentes des plages voisines ont Ã©galement Ã©tÃ© observÃ©es.Les courants mesurÃ©s par l’ADCP RIVER 1200 kW, prÃ©sentent un fonctionnement normal caractÃ©ristique d’une zone fluvio-maritime. This work presents the results of a morpho-dynamic and sedimentological monitoring after beach nourishment and the consecutive formation of a lagoon. Topographic measurements have allowed determining the origin of the sediments present in the lagoon. The movement of the sediments is from the high beach to the lagoon. The analysis of current velocities shows a normal functioning of a fluvio-maritime system with high velocities during the flood period and low velocities during the ebb. Particle size analysis shows that fine-grained sediments are deposited in the underwater part of the beach profile. This first experiment in Senegal had positive results. The recharging of the Pilote Bar beach has favoured the formation of a lagoon. Sedimentation and increase in the height of the slopes of the neighboring beaches were also observed. The currents measured by the ADCP RIVER 1200 kW, indicate a normal operation characteristic of a fluviomaritime zone.