How to detect flooding source (e.g. coastline mistake)?
In the past month, I've seen repeated water-flooding that keeps flipping between flooded/not flooded. This means that map is rendered inconsistently, as seen below.
![half-flooded map][1] - screenshot of [https://www.openstreetmap.org/query?lat=50.06402&lon=14.47634#map=19/50.06396/14.47586][2]
Yet, according to tile status, tiles are clean and rendered at the same time:
[https://tile.openstreetmap.org/19/283225/177664.png/status][3] is a northernmost flooded tile, and [https://tile.openstreetmap.org/19/283225/177663.png/status][4] is one non-flooded just adjacent.
Querying for enclosing features doesn't give any hints as to where the water comes from. Judging from the [flood] questions, this seems to be a coastline error, but as I'm in mainland Europe, the coastline is a bit long for manual inspection. Looking at [OSMi Coastline view][5], I don't see any issues either.
either; and from [http://tile.openstreetmap.org/cgi-bin/debug][6], I see coastline edits a few days old.
Now, my issue isn't "someone fix this instance of the error" (which is not entirely polite, given that I should theoretically be capable of fixing it myself) but rather "how can I find where the error is to fix this"?
[1]: https://help.openstreetmap.org/upfiles/flood.png
[2]: https://www.openstreetmap.org/query?lat=50.06402&lon=14.47634#map=19/50.06396/14.47586
[3]: https://tile.openstreetmap.org/19/283225/177664.png/status
[4]: https://tile.openstreetmap.org/19/283225/177663.png/status
[5]: https://tools.geofabrik.de/osmi/https://tools.geofabrik.de/osmi/
[6]: http://tile.openstreetmap.org/cgi-bin/debug