South banks of lake Baikal flooded.

The south banks of lake Baikal flooded at the moment:

Well if you look at Mapnik tiles. If you change to Osmarender the situation is still normal.

-Is this the richt plcae to post such errors?
-Is it better to post this in the russian subforum?

It breaks at the position where the coastline is splitted.
It seems that one of the coastlines had a wrong direction but that was fixed a few days before.

I merged the coastlines into 2 ways )both are under the 2k limit) and gave the multipolygon a natural=water tag.
I hope that this will fix the rendering bug.

It probably had fixed it but the way the coastline is handled in Mapnik delays the re-rendering of the coastline until it is regenerated. Nevertheless, your merging of the ways is probably a good idea. :slight_smile:
At the moment there is no connection with the points where the two ways join and where the trouble starts.

The flooding is different at different zoomlevels.
Mapnik does not draw all inner ways (islands) of this relation.

Hope that all comes right.

Sorry but I do not quite understand what you mean. Yesterday I forced Mapnik to render new tiles by shortly adding a city (with the name TEST) near the border of Baikal west from Babushkin. After some minutes the tiles were rendered. I saw the TEST city. But the flooding was the same. After that I removed the node.


In Mapnik layer the coastline is not rendered directly from live OSM data but coastlines are periodically preprocessed into shapefiles. Read more at

I apologise, it was very badly phrased. :slight_smile:
JRA has already said what needs to be said.

OSM data is continually being imported into a second database which is used by Mapnik for rendering the OSM Mapnik layer. Coastline data isn’t handled directly though, instead large shapefiles are created every now and then. These are used for the coastline in the OSM Mapnik layer. So your changes to coastlines aren’t going to have any immediate effect, but sooner or later will get imported through a new set of coastline shapefiles.

When it comes to coastlines patience is necessary. I’m currently waiting on some coastline as well, so you’re not alone. :slight_smile:

The flood is over.

But now there is something at Listvianka wich you see if you zoom in:

There’s also a more serious problem going on at

I’ve seen the same sort of problem in GIS applications when rendering huge shapefiles - random vertical lines that appear only at certain zooms. It happens with roads too:

create a bug report in trac for mapnik

edit I fixed it with a forced rerendering

Ok fixed. But here still the same and also at Listvjanka.

Hoe did you force that? Invalidating tiles or so?