Sea Map
This page covers the creation of the project of an open sea map "OpenSeaMap or OseaM. OseaM is part of the OSM project.
Introduction
To date, OSM extends mainly to the continents. The water areas are simply "blue". Of course, traffic will take place on the water. Therefore, the OSeaM will be prepared analogous to the corresponding road map chart.
River maps for the river cruise, canoe maps for canoeists, and others should however be developed in their own projects. OSeaM only is a project name within OSM. Of course OSeaM is just a snippet, and thus an integral part of OSM (though in terms of area with 71% being a fairly big one).
Definition of sea level
The whole thing is complicated: wikipedia: en: Geodetic_system#Vertical_datum How we do it in OSM?
So far, the "shoreline" as natural=coastline as average flood marks.
It is unclear when the river is a coastal indentation. See Proposed features/Tidal Rivers.
It is unclear how low-tide areas (DE:Watt) to be presented satellite map .
It is unclear how water depths are given.
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