Salt evaporation pond facts for kids

Salt evaporation pond in Île de Ré, France

Natural salt evaporation ponds at Pedra de Lume, Sal island, Cape Verde

A Salt evaporation pond (or saltern pond) is a man-made shallow pond. Usually it is located near the sea. The ponds can be filled with salt water. The water is then left to evaporate. The salt is left behind, and can be harvested. Such ponds also provide a habitat for several kinds of animals. Most of these animals are birds.

The color tells how much salt there is left in the water. Green colors come from special algae. These algae are there in low to mid salinity ponds (ponds with little salt in the water). In middle to high salinity ponds, an alga called Dunaliella salina shifts the color to red. Millions of tiny brine shrimp create an orange cast in mid-salinity ponds. Other bacteria such as Stichococcus also contribute tints. These colors are especially interesting to airplane passengers or astronauts passing above due to their somewhat artistic formations of shape and color.

Images for kids

Salt ponds in the San Francisco Bay area. The different colors are from different kinds of microorganisms in the ponds.
Another pond in Aigues-Mortes, in France
The salt, after it has been collected (This one in Batz-sur-Mer, in France
Salt evaporation pond in Île de Ré, France
A salt pan worker in a salt evaporation pond in Tamil Nadu, India.
San Francisco Bay salt ponds
Salt evaporation ponds at a lithium mine in Argentina. The brine in this salar is rich in lithium, and the mine concentrates the brine in the ponds.
Contemporary solar evaporation salt pans on the island of Lanzarote
Solar evaporation ponds in the Atacama Desert
Solar evaporation ponds in the Salt Valley of Añana, Spain
Solar evaporation ponds in the Salt Valley of Añana, Spain