Salt has been harvested in the bay between Le Croisic and Guérance on the edge of Brittany for centuries. The industry had been in decline but in more recent decades has started to grow again with the local attainment of a ‘red label’ quality status for its salt products.

We had the privilege of getting a tour of the salt beds with my old friend from Paris days, Ronan when we stayed with his family in the house he grew up in in Batz-sur-Mer. It was a welcome two-day stop on our Summer Tour.

As Ronan explained:

  • At high tide, sea water flows into reservoirs that stock the water for the day of salt harvesting.
  • This salt water is then directed by an intricate network of channels to blocks of salt beds.
  • Each salt bed is about the size of a typical English allotment. In a salt bed the water from the channels flows in and the flow reduced to almost a stand-still.
  • During the heat of the day, the water evaporates and salt crystals form. There are two salt products: the purer ‘fleur de sel’, which accumulates on the surface; and the darker ‘sel gris’ which accumulates on the bottom.
  • Morning and evening salt harvesters walk out to their salt beds and gently scrape the two types of salt out of the beds and pile them up on the side. Single bed can produce a wheelbarrow-full every day in high summer.
  • The salt harvesters transfer their salt to larger communal salt piles, which are then taken to the town cooperative.
  • Individuals and families have harvesting rights over a specific beds.

I find the salt beds a fascinating example of engineering and commoning. This is a common resource which requires shared infrastructure to harvest. What we take out is bountiful, but requires a shared responsibility for preserving the purity of the resource. Similar to the water irrigation channels that I saw in Mirenna in Spain many years ago.

The salt beds also create wonderful colours. The colour depends on the salt concentration and the angle of the sun.

A group of salt beds at Batz-sur-Mer
The morning’s harvest of fleur de sel is gathered up against the wall
The individual harvests are collected together
The colours of a salt bed
Map of the salt beds of Batz-sur-Met
The very slow flow of water through the salt beds – watch carefully.