Water Leave — Metropole 2017 — BD Carthage

The water leash includes:
— the leash of the highest waters (limit of land never covered by the sea), the continuity of which is ensured throughout the BDCarthage. In the case of islands, it shall be seized only if it delimits an area greater than or equal to 1 hectare;
— the leash of the lowest waters (limit of the land still submerged), where it is more than 100 meters from the leash of the highest waters (otherwise it is not seized) and outside the estuaries (where an arbitrary line closing the estuary is seized in place of the leash of the lowest water). In the case of islands that emerge only at low tide, it is seized only if it delimits an area greater than or equal to 4 hectares.

A leash section is located by geometric arcs, corresponding to the cut-offs by attributes managed by the IGN: nature. The change in 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.