Historical aerial photos of Illinois, state climate and soil data, and interactive geologic maps are just a few of the offerings provided on the Illinois Geospatial Data Clearinghouse, a project of the Illinois State Geological Survey (ISGS). The clearinghouse has become the starting point for the GIS and remote sensing user communities in Illinois, but even hikers and fishermen will find useful data on the site.
Data are provided under the categories of climate, elevation, geology, hydrology, infrastructure, and land cover. Digital orthoimagery collections have prompted requests from Google, Mapquest, Microsoft Earth, and the National Weather Service.
Some of the newer additions to the clearinghouse include a database of 70,000 pages of typed and scanned ISGS field notes, a set of 12 geologic and geophysical maps of the Midwest, and a map viewer of hourly and daily soil moisture and temperature readings across the state.
A popular dataset available is the elevation data obtained through Light Detection and Ranging (LiDAR) technology as part of the Illinois Height Modernization Program. LiDAR derivatives and raw data are available for most of Illinois.
Also of interest for home buyers may be the data on areas that contain sinkholes in Illinois, which are susceptible to aquifer contamination and may also lack the stability required for certain land uses.
Historians may enjoy the Indian treaty boundary lines viewer map, data on the Illinois land cover from the early 1800s, and aerial photography of Illinois from 1937-1947. The collection history gives details about the approximately 33,500 photographic paper prints that were scanned.
For more information about the clearinghouse, visit https://clearinghouse.isgs.illinois.edu/about.