Is the Camargue in danger of disappearing, submerged under salt water? By 2100, the sea level will have risen by 40 to 70 centimeters according to scientists. A trajectory that seems disastrous for the Camargue. The majority of the territory is located less than one meter above sea level.
When they go to the beach, at the end of their land in Saintes-Maries-de-la-mer, Aude Raynaud and her father, Frédéric never bathe. They observe.
They assure it, the sea advances year after year “one or two meters”. Biting inexorably on the pastures of the family of manadiers, located near the mouth of the Petit Rhône at Saintes-Maries-de-la-Mer.
Frédéric’s great-grandfather settled on these lands belonging to the Conservatoire du Littoral in 1950. “At the time, the sea was a kilometer from here. There were blockhouses from the Second World War. They are now under water.”.
Aude confirms. “We had 1000 hectares of land. Today I think we are more around 800. That makes less room to feed our animals.”
The bulls bred by the Raynaud family are renowned. In the middle of a field, Frédéric points to an imposing animal, winner of a Camargue race the previous weekend. “We’re going to leave him alone, he needs to rest.”
To feed it, the Raynauds have to cultivate hay elsewhere, far from the sea. The area here is no longer enough.
For the past twenty years, the rise in water levels has accelerated. The sea rises by precisely 3.7 millimeters every year. In the 20th century, the level only increased by 2 mm per year. “We are only at the beginning of the phenomenon”says François Sabatier, lecturer at the European Center for Research and Education in Environmental Geosciences (CEREGE), in Aix-en-Provence.
If the consequences for the herdsmen are very real, the erosion of the coastline is however not the most immediate danger for the Camargue. “It is an environment in perpetual motion. Erosion has always existed. For the moment, we do not observe any acceleration due to global warming.”
If the beach recedes at the Raynauds, according to François Sabatier, it is due to the dykes built a few kilometers away, to protect the village of Saintes-Maries-de-la-Mer. “When we harden a place, we move the problem elsewhere. On the sides, the decline continues”.
According to the scientist, the main threat to the Camargue is storms. “We are going to feel stronger and more frequent storms, because of the rise in sea level.” Centennial storms, the most powerful, will occur every ten years at the end of the century. Or even every five years according to the most pessimistic scenarios, causing a vicious circle.
Heavy seas aggravate the phenomena of erosion and submersion of the land, and cause a great deal of damage.
Anticipating future public policies for the protection of the Camargue is the mission of Symadrem, the Interregional Joint Syndicate for the Development of Dykes in the Rhône Delta and the Sea.
The organization takes care of the management of the many dykes that protect the Camargue from the onslaught of the waves. This containment policy was launched after the great storm of 1982, when the whole of the Camargue was flooded.
In a diagnosis presented on October 18, the organization estimates that the damage caused by the storms will have an average annual cost in 2100 5 times higher if nothing is done.
“The average annual damage caused by storms is currently 3 million euros over the entire delta. It will be 15 million in 2100”, explains Thibaut Mallet, the director of Symadrem. The cities of Port-Saint-Louis-du-Rhône, Grau-du-Roi and Saintes-Maries-de-la-Mer will be particularly affected.
But you don’t have to wait until the end of the century to see significant changes. In 2030, according to the Symadrem diagnosis, massive seawater flooding, mainly affecting agricultural activities, will have a 65% chance of occurring each year.
Data that confirms Frédéric Raynaud in his intuition. The manadier feels that storms causing seawater flooding have been more frequent in recent years.
To protect him, the municipality of Saintes-Maries-de-la-Mer sent an excavator to his home in the fall of 2021. It erected a fragile sand dike between his land and the saltwater pond. which borders the pastures of the bulls.
A makeshift, but necessary protection explains Aude Raynaud. “When the sea overflows it goes very quickly, in a few minutes it finds itself at the door of the Mas, which is one kilometer from the sea.” Regularly, the family must therefore evacuate, leaving the animals with their feet in the water.
But the biggest problem remains the salt deposited by the sea when it withdraws. “It kills all our pastures”laments Aude.
Increased flooding could therefore make the land unsuitable for cultivation in the future. Long before they disappeared under the water.
If scientists agree that the Camargue will eventually disappear one day or another, the deadline is further away than 2100.
“It will not be for our generation or even that of our grandchildren, we rather on the horizon 200 or 300 years” says Jean Jalbert, biologist and director of the Tour du Valat. In this area located to the east of the Delta, a team of scientists is in the front row to observe the effects of global warming in the Camargue.
“But you have to understand the trajectory we are on. It is painful, it is disastrous. But it is an objective reality. Even if we stop emitting the slightest gram of CO2, the sea will continue to rise for centuries. .”
For him, this awareness must be a driving force for adapting and considering solutions. “Take short-term measures such as rockfill or underwater dykes, why not. But in a few years they may no longer be adapted to the rise in sea level. Other strategies will have to be considered. We must anticipate it now.”
The Tour du Valat, for example, is experimenting with the “renaturation” strategy. The principle seems counter-intuitive. Let nature and storms take their course, rather than protecting with dikes.
“We see that the sea deposits sand with each storm, which creates a new coastal strip. Over the years, it will form dunes which will protect the Camargue against the storms of tomorrow.”
A strategy that cannot be applied where there are dwellings or human activities. For Francois Sabatier, “we must already consider a slow evacuation of the low areas of the Camargue.”
This is precisely the path taken by the Raynaud family. “My father was born here, my sister and I were born here. It’s painful, but we are preparing to abandon these lands. We hope as late as possible,” explains Aude.
The family already owns several hectares in the Gard.
Leave and adapt, to ensure that young children have the opportunity to take over the business, if they wish, when they grow up. And preserve their future.
Find our report on the subject on Monday November 7 in the 12/13 and 19/20 Provence-Alpes edition