Laisse des eaux - Métropole 2016 - BD Carthage

The water leash includes:
- the highest water mark (limit of land never covered by the sea), whose continuity is assured throughout the BDCarthage. In the case of islands, it shall be seized only if it delimits an area of 1 hectare or more;
- the lowest water mark (limit of land always submerged), where it is more than 100 meters distant from the highest water mark (otherwise it is not seized) and outside the estuaries (where an arbitrary line closing the estuary is seized instead of the lowest water mark). In the case of islands that have emerged only at low tide, it shall be seized only if it delimits an area of 4 hectares or more.

A leash section is located by geometric arcs, corresponding to the attribute sections managed by the IGN: nature. Changing the value of an attribute only results in the creation of a leash section if the new value remains constant over a length of at least 1 km.