Lake Retba, also known as Pink Lake, is well known as one of the most salty lakes in the world with approximately 40% salinity. The pink color of the water is due to a type of algae (Dunaliella salina) that is typical of salt lakes. The lake lies near the village of Sangalkam in the Rufisque Department of Senegal, 35 km north of Dakar. It is divided into four sections: Khar Yaala, Khoss, Virage and Daradji.
Extraction of the salt is very labor intensive and usually done by men. They cover themselves in shea butter to protect their skin from the corrosive water before swimming out and breaking the salt crust on the lake bed with long sticks. The salt is then collected with shovels or by diving down and taking it by hand. The harvest is ferried back to shore on a pirogue (traditional boat) where women wait to carry it to drying piles by the lakeside. Each salt collector uses his own initials to mark his drying piles and bags, weighing around 25 kg each and fetching 700 CFA francs depending on the current market price. Before being consumed the salt must be iodized. Pink Lake salt is traditionally used by Senegalese fishermen to preserve fish but its is also sold on to nearby African countries such as Gambia, Guinea, Mali and Benin.
Lake Retba was originally a fresh water lake up until the 1980s when severe drought caused a change in the composition of the water and allowed for people to start harvesting the salt. Unfortunately Lake Retba has become over exploited. With harvest currently around 40,000 to 50,000 tons per year an incredible threat is posed to the biodiversity of this unique environment. Villagers and local authorities would like to impose a rest in production in order to preserve the lake’s ecosystem.