A simple command line utility to generate administrative boundaries from OpenStreetMap via Overpass and OSM Land Polygons.

Please make sure you have installed poetry locally. Then clone this repository and run poetry install from the root folder. In order to generate not only maritime but also land (coastal) boundaries, you will need to download land polygons derived from OpenStreetMap and generiously hosted here. To decrease the computation time please download the WGS84 split variant.

make_boundary --help
usage: make_boundary [-h] -a ALPHA2 [ALPHA2 ...] -f FORMATS [FORMATS ...] [-l ADMIN_LEVEL] [-d LAND_DATA_DIR]
                     [--debug] [--no-debug]

required arguments:
  -a ALPHA2 [ALPHA2 ...], --alpha2 ALPHA2 [ALPHA2 ...]
                        List of ISO-3166-1 alpha2 country codes, e.g. ES FR DE
  -f FORMATS [FORMATS ...], --formats FORMATS [FORMATS ...]
                        Output formats, one or multiple of shp, gpkg, csv, geojson, mapinfo

optional arguments:
  -l ADMIN_LEVEL, --admin_level ADMIN_LEVEL
                        OSM administrative level, currently only level 2 supported. Read more at
                        https://wiki.openstreetmap.org/wiki/Key:admin_level
  -d LAND_DATA_DIR, --land_data_dir LAND_DATA_DIR
                        Path to the OSM land data polygons folder, read more and download from
                        https://osmdata.openstreetmap.de/data/land-polygons.html
  --debug
  --no-debug

Depending on the selected country the processing time will vary. While the maritime boundaries will take a few seconds to be generated, the land boundaries will take longer due superior spatial detail. Land boundaries for countries with with greater coverage, e.g. the United States, Canada or France, can take up to 45 minutes to be generated and will require up to 8g of memory. The reasons are resource hungry geopandas overlay operations intersecting the maritime boundaries with the OSM land polygons dataset.

make_boundary --alpha2 AU --formats geojson

make_boundary --alpha2 ES --formats geojson shp gpkg --land_data_dir /path/to/land-polygons-split-4326

make_boundary --alpha2 FR CA --formats csv --land_data_dir /path/to/land-polygons-split-4326

The file output formats can either be ESRI Shapefile, GeoJSON, CSV, GeoPackage or MapInfo and will be saved as archives into the data folder residing in path/to/nintynine-boundaries/nintynine_boundaries.

The plan is to include further administrative levels for individual countries at a later stage.