A quarter of the French coastline is affected by erosion, a quiet scourge that has already displaced its first victims in France. With increasingly violent storms claiming metres at a time, whole towns are on the verge of engulfment. We can perhaps slow its progress, but how can seaside resorts defy the mighty ocean? The Down to Earth team takes a closer look.
Losing land
The sea engulfs 2.5m per year on some parts of France's Aquitaine coast, causing dunes like the Dune of Pilat to retreat inland.
Rates of erosion are alarming in this region, but the phenomenon is nothing new. The sand found on our beaches is the product of prehistoric glacial erosion inland, but for the last 10,000 years there has been a sand deficit, making our beaches vulnerable to coastal storms.
As a geologist at the Coastal Observation Institute of Aquitaine, Alexandre Nicolae-Lerma is responsible for monitoring the retreat of the coastline. He observes that the Dune of Pilat, the largest of its kind in Europe, around 110 metres high and 3 kilometres long, is under attack. He points out an "erosion notch": an area where the sea regularly removes sand, creating visible wounds in the landscape.
To illustrate the rate of erosion, Nicolae-Lerma uses the example of bunkers constructed on the dunes all along the Atlantic Coast during World War II. He points out that "today most of them are either at the foot of the dunes, on the beaches, or even in the sea".
Quite literally 'on his doorstep'
Fulfilling his lifelong dream to live by the sea, André Laforêt purchased his shorefront property in 2019. But on arrival, he soon saw his neighbours evicted and realised that local authorities would eventually be knocking on his door too as the sea edged closer towards his front door.
"We can't sell because there's an imminent danger," he explains, "but there's no money to compensate us". Laforêt says he is willing to sell his property to the authorities with a 20-30 percent reduction, but without that he will be left with nothing.
French law has the "Barnier Fund" to compensate victims of natural disasters, but beach erosion is not classified as such. Homeowners evicted from the Signal building just north of Biscarrosse in 2014 were denied compensation by the courts, and only received financial relief seven years later in a one-off political decision.
Buying time
Seaside resorts cannot turn back the tide and, in the long-term, the sea will prevail. However, in the absence of a contingency for the likes of Laforêt, a "soft approach" has been adopted.
Vincent Bawedin from the Landes sub-regional council oversees the annual sand replenishment on the beaches of his region. "On average we transport 70,000m³ of sand per year. The record was 2020 with more than 100,000 m³," he explains. The sand is taken from beaches further south and deposited on affected areas such as Biscarrosse, without which there would be no beach.
This is one of myriad actions in the region. For instance, the planting of sea grass on the sand stabilises the dunes, allowing them to better resist the elements.
Bawedin adds: "The effects of erosion are increasingly powerful, increasingly pronounced. It's the dawn of a problem that is going to need to be addressed in the decades to come, to which we don't have the solution."
.png?w=600)
