On the Dewulf dune, which rises on the outskirts of Dunkirk, between a bus terminus and the sea, there are many traces of departures at the end of July, after a few days of favorable weather.
For the coastguards, the day begins with a quick drone flight to identify the main waste.
«Sometimes in the summer, we fill several skips a week with zodiacs and the like,» says the pilot, Florian Boddaert, before setting off with his colleagues on difficult paths.
The pollution is visual, but above all, this accumulation of rubbish disturbs the Natura2000 classified area, which is home to many native species, orchids and wild garlic, or even frogs, newts and birds.
Some fences are frequently damaged by candidates for exile, the guards also had to temporarily remove the goats installed on the site as ecological mowers.
Sometimes, ponds are polluted by gasoline intended for crossings.
From now on, most of the work consists of repairing the damage linked to clandestine departures, «it’s restrictive», according to Aline Bué, head of a team of six guards responsible for watching over 1,000 ha of dunes and natural sites.
– «Seeing children leave» –
Under the cover of thick thickets, sweaters, duvets, strollers, or cans of energy drinks mark the areas where migrants have waited to board. Tear gas canisters can also attest to a police intervention.
On a discreet flat area 300 m from the sea, an inflatable boat, lacerated by the police after a missed departure, awaits collection, surrounded by around forty new life jackets and jerry cans of gasoline.
The coast guards cut the boat, which will be recovered by an equestrian brigade, the only one able to intervene on the narrow sand paths.
Maintenance workers participate in the cleaning, crisscrossing the area on foot.
«One day, I came across a dozen migrants, with a mother who was carrying a baby, and a father who had two boys aged two and four years maximum», recalls their team leader, Mathieu Guerrien.
«The hardest thing is to see children go to the open sea, and come close to death», he is moved.
Since the authorities bunkered the Channel Tunnel and the port of Calais, more and more candidates for exile are trying their luck crossing the busiest sea route in the world.
– «Disastrous impact» –
The Dunkirk coast guards found their first zodiac in 2019. «Since then, we have reached a hundred,» says Aline Bué.
These time-consuming operations encroach on the other missions of the guards, watchdogs for biodiversity: it is difficult to verbalize wild camping in this context, or to find the time to carry out the selective mowing and the inventories of birds, dragonflies and batrachians necessary for the ecosystem health.
Local communities are calling on the state for help.
«We cannot be insensitive to all these departures, (…) it takes me to the guts, but there is also a disastrous environmental impact», deplores Olivier Ryckebusch, mayor of Leffrinckoucke, 4,500 inhabitants.
Worried about the Grand site de France label that the dunes of Flanders are about to receive after 20 years of procedures, he raises the cost of cleaning: in 2021, 20,000 euros just for his municipality.
«We are working on collective solutions for this problem which will last», indicates for his part the sub-prefect of Dunkirk Hervé Tourmente.
The state is conducting «negotiations with the British authorities so that they participate financially in the neutralization and evacuation of nautical equipment,» he adds.