In the oceans, marine currents form gyres—that is, giant whirlpools. These gyres are located at mid-latitudes and are driven by trade winds [i], variations in water density, and the Coriolis force [ii]. Plastic waste discharged into the oceans by human activity is naturally carried by marine currents and partially accumulates in the five gyres identified to date: two in the Atlantic Ocean, two in the...

The issue of floating marine debris is directly linked to human activities on land—not only those near the coasts but also farther inland. Regarding waste, the sea begins far from the shore: on land where streams, rivers, and waterways can carry significant amounts of debris into the oceans. As often seen on urban storm drains, “the sea starts here.” Experts and scientists agree that 80% of marine...

Waterway sweepers Street sweepers are part of the urban landscape, even in small towns like Marcillon-Vallon with its 1,800 inhabitants. Yet these cleaning machines represent a substantial investment: between €100k and €170k for acquisition, and annual operational costs of around €40k to €50k for a full-time maintenance worker and regular servicing. Still, no one questions their usefulness in keeping...