salterns

Salterns are man-made systems of shallow evaporation basins designed to extract salt from seawater or highly saline groundwater. They are typically arranged as a sequence of ponds, each with controlled inflow and outflow, where solar energy and wind drive evaporation and concentration of brine until salt crystals form.

Construction and operation: Seawater is conveyed into first evaporation ponds, where rapid water loss concentrates brine. Water is then transferred through progressively higher-salinity ponds, eventually reaching crystallizer ponds in which halite deposits precipitate. Salt is harvested by mechanical rakes, washed to remove impurities, and dried for packaging. The process relies on climate: hot, dry conditions with steady evaporation are ideal, and operations often align with warm seasons.

Types and products: Open-pan solar saltworks produce coarse sea salt and finer refined salts; in some regions brine wells and solar ponds produce specialty salts such as fleur de sel or salt used in industry. Some salterns also extract by-products or salts with specific mineral blends; brine management may include recycling or mixing for quality control.

Geography and history: Salterns have been used since ancient times to obtain salt for food preservation and other uses. They are found along coastlines worldwide, with long-standing traditions in several European, Asian, and American regions.

Today, some salterns have declined, while others remain active or repurposed as cultural landscapes and biodiversity habitats. Modern operations emphasize water management, environmental safeguards, and efficiency while continuing to supply salt for food, industry, and de-icing.