Canal dug to control flooding

A 4-meter-wide canal, 1.5 meters deep, and about 100 meters long was dug during the night of October 3 to October 4, 2003, in Saint-Louis, Senegal. This was done to lower water levels in the city, which were rising due to heavy rains in the Senegal River basin. The canal provided the river with a direct outlet to the Atlantic Ocean to prevent flooding.

Location of the canal

The canal was dug 7 kilometers south of the Faidherbe Bridge, where the sandbar was the thinnest. This location was chosen to make the excavation easier. Initially, the project succeeded in lowering the water level by about 1 meter and preventing a flood. However, experts later criticized the decision for not considering long-term effects on the sandbar.

Sandbar erosion over time

The Langue de Barbarie, a natural sandbar that protects Saint-Louis from being submerged by the sea, was significantly weakened by the canal. The breach widened rapidly, reaching 80 meters by October 5, 2003, and expanding to 330 meters within three weeks. By 2007, the breach was 1,500 meters wide and 6 meters deep.

Continued expansion of the breach

By February 2015, the breach had grown to 5,200 meters, and by 2016, it measured 5.5 kilometers. The canal became the new mouth of the Senegal River, shifting the river’s outlet from about 30 kilometers upstream to 6 or 7 kilometers south of the island of Saint-Louis. This change altered the river’s flow and impact on the surrounding area.

Environmental and social impacts

The change in the river’s flow increased the size of tides in Saint-Louis, leading to the submersion of two villages, Doun Baba Dièye and Keur Bernard. Keur Bernard was completely lost, while Doun Baba Dièye was partially reoccupied later. The surrounding land, once used for growing crops, has become too salty for farming, and residents of the Mboumbaye lagoon now face frequent tides from the Atlantic. Erosion has also removed dunes and other natural features in the southern part of the area.

Impact on local fishermen

The breach has disrupted the marine ecosystem, creating dangerous conditions for local fishermen. Canoes often capsize in the channel, and reports suggest hundreds of deaths since 2003, though no official numbers are available. Fishermen from Guet Ndar describe returning from fishing as a high-risk activity. By late October 2026, the breach had become a major concern for local fishermen, with Idrissa Ndiaye, newly elected head of the Regional Union of Artisanal Fishermen of Saint-Louis, calling it "the main obstacle for Saint-Louis fishermen." He warns that traditional fishing practices are "in danger" and urges the government to consult with industry stakeholders.

Environmental protection and current state

Despite the challenges, the area remains protected as the Langue de Barbarie National Park was designated a Ramsar wetland on April 7, 2021. The current width of the breach varies, with measurements in 2018 showing 5.2 kilometers and a recent study indicating up to 7 kilometers with two channels. Saint-Louis has not experienced a major river flood since 2003.