Talk:Proposed features/Tidal Rivers

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tidal channels

I've a question regarding tidal channels; I hope this is the appropriate place to ask. I'm working on a map within a tropical mangrove estuary. The mudflats covered by mangroves are cut by large tidal channels partly tagged as "river" in existing coastline data in the neighbourhood. I think, however, that "river" is not really appropriate here -- do you have a suggestion how to tag tidal channels? Thanks! --Umehlig 15:02, 26 April 2008 (UTC)

Ah. In Brazil. Interesting. Are you in Brazil yourself?
It's a tricky question. Do these channels dry up at low tide? Become mud? Tag:waterway=river normally signifies permanent flowing water, but I guess not necessarily. The good thing about tagging it as a river is, it has most of the important properties of a river; You could take a boat down it. You can't cross it on foot easily. etc. But yeah it's more of a coastal inlet than a "river". Maybe add a tidal=yes tag. ...and a surface=mud perhaps.
Proposed features/Water cover tackles these kinds of things, however that all relates to areas, not ways.
-- Harry Wood 18:47, 27 April 2008 (UTC)
Yes, I'm currently in Brazil. The channels do not dry up completely (some almost, we have a tidal amplitude at spring tides > 5 m). At low tide, you can get across on foot sometimes (but it gets *very* muddy); during high tide, you normally can pass with smaller fishing vessels, at low tide even a canoe can get stuck. The more elevated mudflats around the channels are covered by mangrove forest (wetland=mangrove?). I didn't like "river" because for me this implies having some kind of freshwater spring ... May be one could add waterway=tidal_channel some day? Having a centre line in the middle of channel areas as suggested for river areas is probably not necessary, as tide goes in & out ...
Anyway, I tagged the channels as "rivers" for now, and added "tidal=yes"; I'll have a look at the Water cover stuff. Many thanks! --Umehlig 23:19, 27 April 2008 (UTC)
Good stuff. You should create yourself a wiki user page User:Umehlig, and add that page to Category:Users in Brazil. Also I created a section WikiProject Brazil#Natural resources. Not much information there, but I guess this could be a very interesting area for the project to develop. -- Harry Wood 10:06, 28 April 2008 (UTC)
Thanks again. I'll try to convince other collegues from the University Campus here to contribute ... --Ulf Mehlig 14:46, 28 April 2008 (UTC)

Problematic vs. usibility

Sorry for my bad english, might be, I didn't understand th Problem. As it's shown to me, I can't see the difference between the tidal part of a river, a tidal river and a sea-way through / between tidal-flooded land / coastal regions: on board I need to know, where I do have allways water. So I do feel very bad, if I come into a river, which has to less water, without the map shows that. I must know, if and when I shall get enough water, so I want to see altitude-lines even between low- and highwater. If there is 12 m tidal highwater and the flooded area has only 0,5 m depth or 11,5 m depth makes a fromidable difference. But this is just identic in all three cases: it doesn't matter, if I'm in the same situation in a river, in a tidal river or between lowwaterisland.

On the other hand low- and highwater lines will approch in each river. So for me a river beginns at the point of zero-tidal-difference. (And even then I want to see a depth-profil...)

This is, wy I think, we should treat all tidal water in the same way - if I have understood right, what you wrote. --Skipper Michael 16:46, 29 March 2010 (UTC)