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How can I dissolve intersecting polygons with Overpass?

I want to create one polygon of these 3:

[out:json];
(
  area["name:nl"="Antwerpen"]["admin_level"=6];
  area["name:nl"="Limburg"]["admin_level"=6];
  area["name:nl"="Vlaams-Brabant"]["admin_level"=6];
) ->.a;
rel(area.a)["admin_level"=6];
out meta;
way(r);
out geom;

So the ways that are shared should be removed so it would be one area. Any way I could do this with Overpass?

Thanks, Frans

overpass overpass-turbo

asked 19 May '15, 14:44

_Frans_
46●1●1●3
accept rate: 0%

2 Answers:

Overpass API can't to this for you, but you could run the following Overpass API query in QGIS via QuickOSM plugin and merge the resulting polygons according to the description below.

[out:json];
(
  area["name:nl"="Antwerpen"]["admin_level"=6];
  area["name:nl"="Limburg"]["admin_level"=6];
  area["name:nl"="Vlaams-Brabant"]["admin_level"=6];
) ->.a;
(rel(area.a)["admin_level"=6];>;);out meta;

To merge intersecting polygons in QGIS, first select all polygons, then choose "Vector->Geoprocessing Tools->Dissolve" and dissolve by field "osm_type". Save the result in a new shape file and the result to your map. A new layer with a new multilinestring should appear like in the screenshot below.

Please see the following link for details. Here's how the result could look like with a bit of shapeburst styling:

alt text

answered 19 May '15, 16:10

mmd
5.7k●1●53●88
accept rate: 37%

edited 19 May '15, 20:48

Thanks, this solved my problem!

(21 May '15, 13:58) _Frans_

Thanks for answer, this helped me very much.

(03 May '16, 16:22) Chriss85

You can try the webservice from OSM user Wambacher:

https://wambachers-osm.website/boundaries/

and try the "Union" feature at the bottom of the screen after selecting some boundary elements from the tree structure on the left. Then try to export in the format you need.

answered 23 May '15, 19:03

stephan75
12.6k●5●56●210
accept rate: 6%

edited 05 Jul '17, 08:12

Frederik Ramm ♦
82.5k●92●720●1273