Because the bottom of the lagoons remained below sea level, and because the sea is so close, inlets of sea water are formed which, when they evaporate, naturally produce salt. This has meant that, from time immemorial, the salt marshes have been harvested by the inhabitants of the region

 RECENT HISTORY

In 1766, under the administration of the State, the salt marshes at Torrevieja and La Mata began developing salt production for trade.

From 1869, with the liberalisation of the salt trade, the production of the lagoon was privatised, the sites being leased out by the Crown.

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The system of production has changed enormously since the start of exploitation and the labour intensive work of the 18th century has been replaced by a high level of automation.

In 1841, the current method of harvesting was established. The salt is harvested without drying the lagoon, as it had been done up until then.

In 1869, a timber wharf to embark the salt, a floating cable to pull the trail of barges in the Torrevieja lagoon and a railway to transfer the salt to the wharf were built.

In 1923, the lagoon at La Mata was connected to the lagoon at Torrevieja by a pumping station which increased production to 250,000 tonnes a year. The extraction of the salt from the lagoon was mechanised via the invention of ‘Harvester’ machines which replaced the specialised work force. The Levant dyke was then built to improve the protection of the port against the wind and this enhanced the operational facility for loading the boats.

The salt works were nationalised in 1937. From1951 the “Nouvelle Compagnie Locative des Salines de Torrevieja” took over the production and a new modernisation plan was applied to update the existing machinery and build the Ponant dyke.

The last, important technological milestone occurred in 1970 with the ‘Pinoso’ project. This increased the production of salt at Torrevieja by bringing in saturated brine via a 52-kilometer pipe from the Cabezo de Pinoso salt deposit.

Current environmental concerns, which affect all sectors of the economy, have opened up possibilities for improving production. Salt production is an example of an economic activity which is performed in a valuable ecosystem and which actually preserves this precious environment.

The lagoons at Torrevieja and La Mata are some of the principal wetlands in Spain. In 1988, they were declared a nature area and, in 1996, they became nature reserves. The lagoons were also declared Wetlands of International Importance by the Ramsar Convention and a European Union SPA (Special Protection Area) for birds.

  THE PROCESS

The production of salt is obtained by evaporating the water in the brine, via the combined action of several factors: principally, solar radiation and wind.

Saturation occurs when the concentration of NaCl (sodium chloride) reaches approximately 260 gr/l. From this moment, if the evaporation continues, the precipitation of the salt crystals starts and these crystals are deposited on the bottom of the lagoon.

 During years when the climate is normal, crystallisation starts at the end of spring and reaches its maximum period in July and August.

The salt is extracted from the bottom of the lagoon using special ‘Harvester’ machines. These machines have an inclined blade which separates the layer of salt from the bottom of the lagoon and loads it onto the boats. The boats transport the salt to an unloading facility, where it is washed and transformed into an industrial product or ‘sea’ salt (also called common salt). 

From very recent times, certain sectors of the market have increasingly called for products with specific characteristics (generally speaking, a lower humidity rate) and NCA Salines de Torrevieja S.A. was a pioneer in establishing new processes to satisfy these market sectors.

 http://www2.cth.gva.es/parques/ingles/mata.asf