GEOSPATIAL DATA REPORT : Finding and Using GIS Data

http://www.census.gov/geo/www/tiger/tgrshp2009/tgrshp2009.html
(or directly from http://www2.census.gov/geo/tiger/)

2009 version just came out on 10/1/09! Previous versions are also linked from this site.

The TIGER/Line Shapefiles are extracts containing selected geographic and cartographic information from the Census Bureau’s MAF/TIGER® database. Unlike the previous Cartographic Boundary Files site, this site includes block boundary files as well as hydrography, transportation/streets and landmark data files. Users can also download multiple TIGER/Line Shapefiles at a time via this FTP site.

Again, these files contain no demographic information but are designed to be used with decennial census population and housing data as well as other related federal datasets.

http://openstreetmap.org/

“OpenStreetMap creates and provides free geographic data such as street maps to anyone who wants them. The project was started because most maps you think of as free actually have legal or technical restrictions on their use, holding back people from using them in creative, productive, or unexpected ways.” http://wiki.openstreetmap.org/

With Map Quest, Google Maps and Google Earth, street data seems to be available anywhere and to everybody but it really wasn’t. Data may have been developed very slowly at a local government (i.e. developing countries) or data isn’t freely available because of data proprietorship issues. But wait – we have OSM now! OpenStreetMap (OSM) is a unique and innovative data initiative, making hard-to-get street data available to everybody who needs them. Data submitted by contributors are available for downloading for various purposes, including GPS.

Data downloading options at OSM are limited to XML, images and HTML, but shapefiles/GIS data format option is available at the following sites:

http://www.geofabrik.de/data/download.html

Geofabrik downloads server makes OSM derived shapefiles available for free, which are updated everyday.

http://downloads.cloudmade.com/

CloudMade downloads site also offers OSM derived free shapefiles (and other useful datasets.) I don’t know how frequently data have been updated.. I like the way the data are organized by country.

I downloaded the OSM derived shapefiles for Mali and Japan. Mali street networks weren’t many. The Japan street data were fairly good for free, covering major roads of Tokyo for example. Attribute data are fairly limited – like street names. Even the street names of Tokyo major streets are sporadic. BUT, it’s free – I definitely look forward to the future OSM data development.

http://www.stats.govt.nz/statistics-by-area/geography-mapping/digital-boundaries.htm

Digital Boundaries are electronic files of the various geographic boundaries (in digitised form) for use in mapping and geographic information systems (GIS). Meshblock boundaries, and boundaries of larger areas, are available digitally.

Also available from this site are:

• Streets file – an electronic list of address ranges and street names that fall within meshblocks, which can be used to geocode addresses to meshblocks
• Area files – an electronic list that classifies meshblocks into larger geographic areas. The Area files, also known as a concordance file, provide a mapping of the geographic hierarchies so you can see how the various geographic boundaries link together

http://geodepot.statcan.ca/Diss/Data/Data_e.cfm

Census geography covers a wide range of geographic areas – from provinces and territories down to city blocks. These geographic areas have boundaries, names, and other information that make it possible to locate them on the ground and to relate census data to them.

Two major datasets available from here are:

• Census boundary files
• Road network file, 2005

The Canadian Road Network includes address ranges for street segments and thus probably the best free source for geocoding Canadian address locations. I believe this is the source data for the free Canadian geocoder site, http://geocoder.ca/ .

See also: http://www.statcan.gc.ca/mgeo/index-eng.htm

http://www.cityofchicago.org/gis

City of Chicago GIS dataset, printable maps and interactive maps are available from this site. To access GIS data files, click on “GIS Data” or select categorized datasets.

Note: Come back often to this site to get the latest data – the City of Chicago GIS irregularly updates data files – and you cannot tell which files were updated until you download data and compare!  For example, well sought after geocodable Chicago streets shapefiles, TRANSPORTATION_DSLV_1.zip, are now available from the site. Still, no metadata comes with the files..

Datasets available from the site area are categorized into the following groups:

• Base data
• Boundary data
• Incentive programs
• Points of interest
• Transportation Data