Tide mark

Refers to the extreme limit reached by the sea in a given day. The lowest tide mark is the limit of continuously submerged lands. It is distant more than 100 metres from the high-flow mark (otherwise it is not entered) and outside estuaries (where an arbitrary line closing the estuary is entered instead of the lowest tide mark). In the case of islands only emerged at low tide, it is entered if it delimits a zone with a surface area greater than or equal to 4 hectares. The high-flow mark is the boundary of the land never covered by the sea. Continuity is ensured in the entire Carthage database (reference dataset on hydrography). In the case of islands, it is entered only if it delimits a zone with a surface greater than or equal to 1 hectare.