• Throughout France, drought and the lack of effective rainfall are worrisome, especially for the production of drinking water.
  • On the island of Sein, there is no risk of running out of water. To water its inhabitants, the island pumps seawater and transforms it.
  • An ingenious system that offers independence to the island but which costs it dearly, as well as its inhabitants who pay four times the price of the continent.

To our knowledge, this is a unique case in France. Nestled a few kilometers from the famous Pointe du Raz, the island of Sein seems to be the only one to drink sea water in France. On this pebble of South Finistère, there are between 120 and 150 inhabitants in winter. A figure that climbs to a thousand during the summer season when some tourists take the boat to blow in the spray of the Atlantic. Here as throughout the country, there is concern about the consequences of the low rainfall at the beginning of the year. According to Meteo-France, the country did not experience any real rain for thirty-two days, the longest weather drought ever recorded. Data that raises fears of a disruption in the supply of drinking water in some regions. But not in Sein, where the available reservoir is huge. The problem is that it is as high as the bill of the taxpayers who buy from it. Welcome to the land of seawater.

The island cannot pump during storms

Before arriving at the tap of the Sénans, the water of the Atlantic must obviously be treated. For this, the island has two reverse osmosis systems, arrived about twenty years ago. Before that, it was a boiler that was used. Developed by SLCE, reverse osmosis systems normally equip French Navy ships to desalinate seawater on board. "We have two. The largest can treat up to 140 m³ of water per day, the smallest comes as a supplement and can treat 30 m³," explains Mayor Didier Fouquet. More than enough to meet the needs of the inhabitants, even in summer, but do not forget to fill the reserves. Regularly confronted with storms, the island can not pump in all weather and sometimes has to cut the valves. "But we have never been deprived of water," says the mayor. In January, a blackout disrupted the supply and the municipality distributed bottled water.

Who is Sein's drinking water saboteur?

On the island, "everyone is aware of the scarcity of water," comments the owner of a restaurant. Here, almost all the houses are equipped with rainwater collectors and waste has no place. A strange case of a saboteur who would "have fun" wasting drinking water has been shaking the island for a few months. The municipality filed a complaint, hoping to put an end to this regular waste. Because in Sein, water is a precious commodity. And above all a very expensive good. "People always think that seawater is free and that it doesn't cost us much. But it's quite the opposite! " assures the mayor. Despite the financial efforts of the municipality, the cubic meter of drinking water is charged 7.55 euros, four times more than on the mainland, where it costs an average of 2 euros per 1,000 liters. "The products we use to treat water are very expensive, as is the replacement of equipment that deteriorates over time."

This staggering cost also explains why the island of Sein is one of the few territories not to be integrated into a community of communes. "Nobody wants us," laughs the mayor. It is also impossible to pipe the bottom of the ocean for 26 kilometers. The attempt made in the past with telephone cables had not resisted the onslaught of the swell.

What does water taste like without salt?

And what does this desalinated water taste like? "The same as on the continent," says the mayor. Reached by phone, a couple from the island is more reserved. "You don't feel salt. But sometimes it has a rusty color, it has a different taste, "explain this man and woman who prefer to remain anonymous. They even noticed a strange phenomenon. In Sein, a hot water tank would last only two or three years, where it can live up to fifteen years on the continent. "In Sein, everything that is metallic does not last very long," tempers the mayor Didier Fouquet, who had never heard of this inconvenience. The ocean is generous but does not give gifts.

  • Planet
  • Quimper
  • Brittany
  • Island
  • Water
  • Drinking water
  • Sea
  • Ocean
  • Atlantic Ocean
  • Drought
  • Rennes