Vielen Dank für Deinen Kommentar. Es wäre schon nett gewesen, kurz zu fragen, warum ich das gemacht habe.

Hier also meine Erklärung:
Auf allen herkömmlichen Karten sind diese Areale nicht als Teil des Meeres abgebildet, sondern als Landfläche, die regelmäßig von Salzwasser überflutet wird. Da aber auch auf den Satellitenbildern in diesem Bereich dennoch immer wieder Bebauung zu finden ist, halte ich es nicht für richtig, den Bereich als Meeresfläche auszuweisen. So werden auf TPC-Karten diese Gebiete anderes dargestellt als z.B. das deutsche Wattengebiet, das dem Meer zugeordnet wird (Mouth of Indus: TPC J-8A, Wattenmeer: TPC E-2B). Auf der JOG-Karte NF 42-2 sind auch populated places gekennzeichnet, sowie Höhenangaben, die zwischen 10 und bis an die 40 ft betragen.

Wenn diese Areale als Meer klassifiziert werden, nur weil sie von Salzwasser überspült werden, müssten genauso die Salzwiesen der Friesischen Inseln Meeresfläche sein, denn auch diese werden regelmäßig von Salzwasser bedeckt. Aber diese werden auch in OSM nicht als Meer gekennzeichnet. (Beispiel: osm.org/?mlat=53.4882&mlon=6.2433#map=12/53.4882/6.2433)

Zudem trug die frühere landeinwärts gelegene Küstenlinie den PGS-Tag und sah auf den Satellitenbildern auch entsprechend "falsch" aus.

All das habe ich zum Anlass genommen, das Gebiet zu überarbeiten.

Thanks for pointing out this difference! I found the tag "seamark:fishing_facility:category=weir" for objects like these and changed all "waterway=weir" tags accordingly

"hires" polygons are remaining parts of indicating where high resolution images were available. Meanwhile they can be deleted because there is almost no part in the world without "hires" images. It would make more sense to indicate where they are missing...

Thank you for working with me on this great challenge!

Ok, this means that a multipolygon with the outermost ways is not the right choice. How about a boundary relation? According to taginfo there is also a usage of "boundary=natural" (https://taginfo.openstreetmap.org/keys/boundary#values). With this there would be no overlapping of wetland definitions. I have changed the relation now to this.

If you have another idea, feel free to adjust that as well.

Das war auch die größte Herausforderung...
Ich habe die Relation daher nur zu einem Teil geladen, innerhalb dieses Bereichs dann Elemente für eine Sub-Relation herausgenommen und diese Änderungen hochgeladen. Temporär gab es dadurch fehlerhafte Rollen in der originalen Relation (einige neue "outer" waren außerhalb des geladenen Bereichs noch als "inner" gekennzeichnet), aber das habe ich in Kauf genommen und per note darauf hingewiesen. Für jedes weitere Teil habe ich diese Schritte wieder in einem leeren JOSM durchgeführt. So hielt sich die zu verarbeitende Datenmenge jeweils in Grenzen.

:-) Done.

Das original Multipolygon enthält jetzt nur noch die Außenlinie und die größten Inseln. Alle Teilrelationen (nun ohne Namen) sind in einer "collection" zusammengefasst. Manche sind noch immer etwas zu groß, aber nun lässt sich das alles leichter handhaben.

Yes, a lot of work would need to be done here. My goal is first of all to make the "Okavango Delta" relations manageable.

It would also be possible to create a large "Okavango Delta" relation containing only the outermost boundary. All other relations would then be configured as "wetland" without a name. What do you think of this idea?

Currently there is only the way of a "collection" relation, which contains all "wetland/Okavango Delta" sub-relations.

I am not sure. Super relations are described in the wiki only for paths, not for areas (osm.wiki/Relation:superroute). I would therefore only use it as a container with the name tag. In addition, it would also have to be considered whether it makes sense at all to name exclusively the wetland relations as "Okavango Delta", because the water areas, the rivers etc. belong to it as well. And these are not currently part of it. A super-relation could combine them all. So different wetland types could also be part of it.

Yes, it's a big challenge, but now I'm almost done with the first pass. Currently all relations are named "Okavango Delta (Part xxx)", this helps me to keep the overview. Still some parts are bigger than recommended in the wiki, I have to divide them further. (See osm.wiki/Relation#Size: "... up to 300 members".) At last, all relations should be combined in a new relation, which will be just called "Okavango Delta".

I have only made a technical division, no adjustment of the tags. This can be done later by other mappers if necessary.

These are definitely river flows. They do not carry water all the time, so the way must actually get the additional tag "intermittent".

On satellite images you can see at the coordinate 9°59'08.5 "N 34°07'03.8 "E a thin watercourse within the riverbed. River courses usually have a lot of curves and follow the elevation profile, there are always confluences like for example at 10°02'09.4 "N 34°09'55.1 "E. And sometimes you can see by the vegetation that there is occasionally water running here, there are e.g. bigger plants at the river banks.

Roads run straighter and connect settlements. They are also considerably narrower, e.g. at 9°59'02.5 "N 34°06'32.9 "E, especially in a rather sparsely populated area.

So your way/1025570858 should be a river, too...

Oh, shit! There was some confusion within JOSM, but the JOSM conflict tool did not give me the option to chose the right ways.

Thanks for pointing that out! I have corrected the relation now.

A few years ago, Bing satellite images were not high resolution across the board. Some mappers marked the zones in the database where only low resolutions could be seen. At that time I probably adjusted such a zone. Actually these zones did not belong in the database, because they are not real objects "on the ground". Whenever I find one today, I delete these polygons. Because the satellite images are in high resolution almost everywhere.

Meine Quelle ist das PDF auf der Seite https://www.vettweiss.de/freizeit/natur-wandern.php.
Ich habe aber weder die betroffene Relation, noch den doppelten Weg editiert, wie sich aus den history-Daten ablesen lässt:
History der von Dir angemerkten Relation: relation/1027098/history
History Weg 31313644: way/31313644/history
History Weg 31313648: way/31313648/history

Ich bin diesen Weg damals auch nicht gelaufen...

Thanks for pointing out this wrong tag to me, it was originated by the first mapper. I have deleted the tag, this way is a waterway.

I have divided the bulky huge multipolygon of the region into smaller parts. At changeset/61293082 (changeset/61293082) there was a similar situation in 2018. Consensus according to the wiki is to create smaller multipolygons in principle ((waterway=riverbank#Choice_of_size_of_the_multipolygon_relations_for_riverbank_mapping). The validator in JOSM did not report any errors during these changesets, it is quite reliable in this respect.

The fact that I have added many areas of floating vegetation to the wetland zone may be too strict in some areas, but there are many possibilities to differentiate wetland (swamp/ bog/ fen/ marsh/ mud/ reedbed/ wet_meadow/ saltmarsh/ tidalflat/ mangrove) with the possibility to mark temporary flooding (tidal/ seasonal). Thus, such areas can be more accurately captured than by a simple water tag. The original ways have been retained in the database (with a corresponding note), they can be used to make these differentiations.

I've checked this way and two others nearby, but I could not reconstruct this edits. I have deleted the three ways.

I*ve done this work because the original MP had a note saying "This unmaintainable giant MP has to be split".

:-D

Oops, I'm sorry, this must be happened by mistake. I've recreated the relation now.

Sorry, if there has this effect happened. In the next days I'll go through the area to improve the data.