Near Montpellier, a Danish dredger to resilt Petit Travers beach

Le Magni, drague de 75 m de la flotte Rohde Nielsen, décharge sa cargaison de sable devant Carnon. Midi Libre – MiKAEL ANISSET

Since Tuesday February 27, Rohde Nielsen's barge has been sucking up sand in front of La Grande-Motte to fill in the spaces between the three new groynes of the Petit Travers. More than 40 m of coastline gained in the long term.

In front of the Petit Travers, the red buoy can just be seen on the horizon. Attached to the buoy, one end, then a chain. And at the chain, a submerged coupler which will make the junction with 700 m of steel pipes, 80 cm in diameter, installed up to the beach by the Occitan construction company Cazal.

The ship approaching the red buoy impresses the gathered onlookers on this sunny Thursday. The “Magni”, a 75 m vessel from the Danish group Rohde Nielsen specializing in dredging and coastal protection, which arrived in the area on Tuesday, began its rotations on Wednesday evening.

The Dane Tobias Leysen (left), by Rodde Neilsen, and Maxime Bel, site manager of the Occitan construction company Cazal. PCa

For ten days 24 hours a day

"Our team works in shifts, 24 hours a day, explains Maxime Bel, the site manager of the Cazal site. And there we are for ten days non-stop!" Between two walkie-talkie calls with his men at the controls of 35 t monsters, the site manager keeps an eye out. "It's about to start, I saw Tobias' car pass."

Tobias Leysen is Rohde Nielsen's project engineer, who joined Carnon by road. "We move 3,500 to 4,000 m³ of sand per day, he explains in exotic French. The objective, for our team of 8 men on the dredger, is to ultimately bring here 40,000 m³."

"If the weather remains favorable"

The Magni took the sand at the exit of the port of La Grande-Motte, in an accretion zone off the coast of Couchant. These samples, taken on inert bottoms 200 m from the edge, will reinforce the dune cord inside the three newly created groynes at Petit Travers.

"Between the two points, for the Magni, continues Maxime Bel, c’ is half an hour one way, 40 minutes unloading, half an hour return and one hour loading. We should go through six rotations this Thursday."

"If the weather remains favorable, completes Tobias Leysen, we're here for ten days."

Machines, wheels and tracks in the water

The huge dredge has just connected. After a few minutes, muddy sprays of dark sand spring up onto the beach, at the mouth held in place by a backhoe.

The two settling tanks fill at a dizzying pace, while the machines resume their ballet, wheels and tracks in the water. The onlookers can't believe it.

"Ultimately, the operation will allow the beach to gain at least 40 meters, or even more in places, indicates Maxime Bel, experienced in projects of this type. I carried out similar work on the coastline, in Sète, Sérignan or Valras."One eye on his smartphone where an app allows him to follow live the position of the Magni heading back towards the Pyramids, the site manager says with a smile: "And at night, we don't see not the buoy, but with all the lighting, it's not bad too!"

Within ten days, the space between the three new groynes will have been re-silted. Midi Libre – MiKAEL ANISSET

A €1.8M project

The community the Pays de l’Or agglomeration department is the project manager for this work which, at the end of March, will have lasted for 100 years. six months. "They fall within the framework of the 2015-2020 State Region plan contract, detailed Sylvain Ribeyre, deputy secretary general at the Agglo. Their start-up was very slow. delay by the length of the studies."

The operation carried out by the Agglo and its Gemapi competence on the management of the coastline is probably the last of the kind. "It represents an overall budget of 1.8 M€ excluding taxes, continues the manager of the water and natural spaces center of the Agglo. Of this amount, the work itself represents a budget of 1.5 M€, a third of which goes to Rodde Neilsen."

I subscribe to read more