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Overview

OpenStreetMap (OSM) is a collaborative 'volunteered geographic information' project designed to create a free editable geographic database of the world.  OSM is not an original geographic data source but a repository of registered contributor's inputs from manual surveys, GPS devices, aerial photography , and other free sources.  (Read more about OSM at its its Wikipedia article.)

This page describes a workflow for acquiring and using OSM data as a shapefile.  It is not the only way and suggestions (in the comments box below) for enhancing this page are welcomed.

Acquiring OSM data

OSM ArcMap layer

The easiest way to incorporate OSM data with ArcGIS ArcMap is to add the 'OpenStreetMap' basemap layer to ArcMap.  This provides a tiled background layer like the one shown on the OSM website that can not be interrogated or differently symbolized.  It is normally preferable to acquire data that can be converted to a shapefile.

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A recommended .  

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Click Add data > Add basemap...

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Select OpenStreetMap > Add

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ArcGIS will add an OSM layer to the active frame.

The symbolization and content of the ArcGIS OSM layer cannot be changed.

Geofabrik

A free source of OSM data that can be obtained as a shapefile is Geofabrik Downloads.  Links to others are available here on the OSM website.  

The Geofabrik download page offers extracts of each continent, and links to sub-regional extracts.  Most continental extracts are only available in .pbf or .bz2 formats but the the continental pages have sub-regional extracts that are mostly available also as shapefiles.  (Conversion of .pbf files to shapefiles is described below.)  Geofabrik downloads contain all OSM data except the particular each feature's contribution metadata.

Most available Geofabrik extracts have been were acquired from OSM within in the previous two days.  (The download pages document the actual acquisition date.)  This could be critical during a sudden-onset crisis for which contributors make timely updates.

Example Geofabrik download resource options:

Global download page containing extracts and links to continent pages such as:

Central America download page containing .pbf, .bz2, and in most cases shapefile extracts, and links to sub-region pages such as:

Jamaica download page containing .pbf and shapefile extracts

Some locations are not available in sub-regional extracts.  For instance, Bermuda is only available as part of the North America extract - and only as a .bpf or .bz2 file.

Using

Geofabrik data

Gepfabrik Geofabrik .pbf extracts opened with QGIS deliver 'lines', 'multilinestrings', 'multipolygons', 'other_relations', and 'points' layers.  These can be exported to shapefiles with topologically unstructured overlapping features.  The 'multipolygons' layer, for instance, has fields like 'aeroway', 'boundary' and 'natural'.  Features are tagged in one or more of these fields so 'natural', for instance, can contain features tagged as 'water', 'beach', 'coastline', among others.  A water polygon layer could therefore be created from the 'multipolygons' layer of the .pbf file with a filter or definition query for 'natural' = 'water'.

If a Geofabrik Geofabrik extracts that are not available as shapefiles can be imported into QGIS for subsequent use and / or conversion.  But if a Geofabrik extract is available as a shapefiles shapefile it may be an easier and and more reliable way of preparing the desired features.  In the case of the area shown in the ArcGIS OSM basemap (above) one water polygon feature appears only in the .pbf 'lines' extract - and without any tag.

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OpenStreetMap .pbf lines file.    

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Geofabrik shapefile 'multpolygons' extract filtered for 'natural' = 'water'

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Geofabrik shapefile 'multilinestrings'.  Note that only some of the water polygon edges seem to be included as a 'multilinestring'.

extract filtered for 'natural' = 'water'

The line features marking the lake with an island (clearly visible in the ArcMap basemap rendering) is has no tags in the 'waterway' or any other field.

Nevertheless the Geofabrik 

Outputs/Resources

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