OpenStreetMap

OpenStreetMap (OSM) is an open source website that provides open map data from user contributions (not official sources). While this allows for data to be updated more quickly, the type of data available for each location varies. Therefore, you must first check if the data you need is available on OSM's website. If OSM does not have the data you need, please talk to a staff member.

  1. Open a web browser and go to http://www.openstreetmap.org/.
  2. Zoom in to your desired location.
  3. Check if the spatial data you need (roads, building footprints, etc.) is available for that location.

Now that you have ensured that the data is available, you can extract the data. 

Geofabrik Downloads

This method extracts OSM data into shapefiles that each represent roads, building footprints, waterways, etc. 

Geofabrik Downloads offers regularly-updated extracts of continents, countries, and selected cities.

  1. Open the website in a browser.
  2. Click on the Export tab on the top of OpenStreetMap web page.
  3. From the menu, go to Geofabrik Downloads.
  4. From the table, click on the Sub-Region your area of interested is located in. Some countries and regions are subdivided into smaller datasets.
  5. Find and click on the link with .shp.zip file extension, which yields ESRI compatible shape files when unzipped.

 

Assigning a Projection

Before exporting to CAD, it is important to assign a projection to the map. Without a projection, the data is not usable in CAD.

  1. In the Analysis tab, click Tools.
  2. In the search bar, type 'Project.'
  3. Click on the Project (Data Management Tools) tool.
  4. Select the layer from the 'Input Dataset or Feature Class' drop-down menu.
  5. Click the Select coordinate system icon next to 'Output Coordinate System'.
  6. Click the Projected Coordinate Systems folder. For a very specific GIS project, it is important to research the appropriate projection. However, if you are working on a general architecture project, there are several basic ways to choose which projection to use:
    1. Consult the map hanging above computer 3 in the GIS computer lab. Find the UTM zone where your area of interest is located and choose the projection that corresponds with this zone in the UTM folder.
    2. Use the search tool to search the country of your area of interest and choose a reasonable projection from the search results.
    3. Navigate to the National Grids folder and find the folder for the country where your area of interest is located. Choose a suitable projection from this folder.
  7. Run the projection on one layer first to make sure that it works.
  8. If this process is successful, use the projection on all layers using the Batch Project tool.

Now, you are ready to export to CAD.


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