OpenSeaMap Forum

Ackman

Member

Registered: 2015-06-14

Posts: 2

Adding sandbars to the OpenSeaMap

How do I add sandbars and underwater obstructions to the map? Can't seem to find the tag in the JOSM.

kannix

Member

From: Ruhrgebiet

Registered: 2013-10-27

Posts: 148

Website

Re: Adding sandbars to the OpenSeaMap

Hi,

full list of seamark objects: http://wiki.openstreetmap.org/wiki/Open … rk_Objects

Have a nice day, Dirk

malcolmh

Member

From: Hull, UK

Registered: 2012-09-05

Posts: 194

Re: Adding sandbars to the OpenSeaMap

A sandbar is not a marine chartable object, therefore has no "seamark:type" tag. It is a topographical feature, and as such would appear in charts as a depth area. However, OSM do not want us to put any depth data into the database. That is why we have started a separate project for crowd-sourced depth soundings, with the data to be kept separate from the main OSM DB. This project is still under development - you can find information here: http://depth.openseamap.org/

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Malcolm Herring, Developer

zenfunk

Member

Registered: 2014-08-13

Posts: 22

Re: Adding sandbars to the OpenSeaMap

When the sandbank is drying at low tide one could tag it as wetland=tidalflat.

For the others, how about seamark:type=obstruction;  seamark:obstruction:category=sandbank

Or:  seamark:type=sea_area; seamark:sea_area:category=shoal

The latter is already rendered, see: http://map.openseamap.org/?zoom=16&lat= … F0FFFFFFFF .

I have to admit that this tag it is not super useful, but it is more useful than having no information at all. Very shallow areas could be mapped sometimes by satellite imagery. Very usefull where noone dares to go over the shallows with his/her depth sounder.

Any thoughts?

Have a nice day,
Christian

malcolmh

Member

From: Hull, UK

Registered: 2012-09-05

Posts: 194

Re: Adding sandbars to the OpenSeaMap

There is no such obstruction category as "sandbank". The obstruction object type is for man-made features - see: https://wiki.openstreetmap.org/wiki/Ope … 8CATOBS.29

Tidalflats are rendered on the base map and shoal areas are rendered on the seamark layer.

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Malcolm Herring, Developer

zenfunk

Member

Registered: 2014-08-13

Posts: 22

Re: Adding sandbars to the OpenSeaMap

Hm, should we change the Wikipage then?
http://wiki.openstreetmap.org/wiki/Open … rk_Objects
There it says:

Obstructions are: "In marine navigation, anything that hinders or prevents movement, particularly anything that endangers or prevents passage of a vessel. "

Could be changed to e.g. "In marine navigation, anything MAN-MADE that hinders or prevents movement, particularly anything that endangers or prevents passage of a vessel. "

Cheers,
Christian

malcolmh

Member

From: Hull, UK

Registered: 2012-09-05

Posts: 194

Re: Adding sandbars to the OpenSeaMap

The descriptions, objects and categories are exactly as defined in the IHO S-57 catalogue. It is for them to be more precise in their documentation!

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Malcolm Herring, Developer