Librarian
City, County, State, and Other Location Based Collections
At least in the US, it is common to find open data repositories for large populations at the city, county, and state levels. These repositories pull together data from multiple sources for their area of interest. Some examples of these repositories are below. Note that sometimes open data repositories include GIS-formatted datasets and other times GIS data have their own separate repositories.
How to proceed:
- Identify the geographic levels that might collect and share data for the location you are studying and search by name and open data (e.g. Chicago open data)
- For US federal and state portals, first check the "US Government GIS Data - Federal and State Portals" listing below, then
- Search online for the areas of interest, one at a time, (e.g, Chicago, Cook County, Illinois, etc.) by name with phrases like "open data," "data portal," "spatial data," "gis data," "geospatial data."
U.S. Federal and State Spatial Data Portals
- US Government GIS Data - Federal and State Portals
This link opens in a new window
Wei-Hsin Fu in the Carleton Spatial Analysis Lab maintains this comprehensive list of portals to GIS data maintained by federal and state angencies.
Examples of Portals from Cities, Counties, States, and the Nation
- Chicago Data PortalA city-wide collection of open data, both spatial and nonspatial (about 1700 datasets)
- NYC Open Data: 2018 Central Park Squirrel CensusAn example of a spatial dataset located in a city-wide open data portal.
- Bexar County Open Data PortalA county-wide repository of both spatial and non-spatial data collected by and for Bexar County, Texas
- Minnesota Geospatial CommonsA state-wide repository of GIS formatted data for Minnesota (over 1000 datasets)
- Water-Table Elevation and Depth to Water Table, Minnesota Hydrogeology Atlas Series HG-03A dataset available in the MN Geospatial Commons, featuring water table elevation from the Natural Resources Conservation Service
- Massachusetts Energy & Environmental Affairs Data PortalA state-wide collection of open environmental data. A hybrid of a location-based, topical repository.
- Data.govA nation-wide repository of open data across many topics. Limit by file type to locate data resources, for example, Shapefile, CSV, TXT, XLS, etc.
Example: Relevant portals if you want data about LA
- Los Angeles GeoHubA city-wide collection of mostly spatial open data (nearly 1300 datasets)
- County of Los Angeles Enterprise GISA county-wide collection of GIS data for Los Angeles County. Notice how you need to spend time in both Los Angeles sites to get a sense of what to expect in each one. (Nearly 600 datasets)
- California Open Data PortalA state-wide collection of open data (over 7000 datasets)
- California State GeoportalA state-wide collection of open spatial data (Over 6000 datasets)
Local (City, County, Etc.) Agencies that Share Data
Open data portals get their data from government agencies and organizations within their geographic area. Sometimes those portals are comprehensive and other times they only scratch the surface of what is available. Often the originating agencies offer more data than what they share with the larger portals. It's a good idea to identify the agencies that collect the kind of data you're interested in and look for the data they share. Some examples are below to give you an idea.
- Minnesota State Demographic CenterDemographic data by topic for the state of Minnesota
- County Data - Association of Minnesota CountiesA collection of datasets about Minnesota counties
