Josh Tanner, GIS Specialist
Geographic Information Systems
141 South Main Street, Suite 501
Decatur, IL 62523
Phone: (217) 425-5733
Fax: (217) 424-1459
M-F 8:30 a.m. to 4:30 p.m.
excluding legal holidays
GIS services are located in the Macon County Planning and Zoning Office. GIS is a computer system that is capable of linking, holding and using data that are related by a geographic location. Examples include property boundaries, addresses, zoning districts, streets and roads, bike trails, precincts and election districts.
GIS is a tremendously powerful resource when mapping or performing land based analysis. It is an analytical tool using locational associations or relationships of different data, allowing the information to be displayed in a visual form. The principal use of GIS is decision making. By providing broad analysis capabilities, various comparisons of numerous geographic data layers along with traditional databases. GIS enhances the County's ability to make the best decisions in the shortest amount of time.
Questions that GIS can help answer include:
- Location: "Where is it?"
- Condition: "What is located at…"
- Trends: "What has changed since…"
- Patterns: "What spatial patterns exist?"
- Modeling: "What if…"
Recently the County contracted with the Army Corp of Engineers to
acquire Light Detection and Ranging (LIDAR) data for
the entire county. This data will be used to create a Digital
Eleveation Model (DEM), a three dimensional model of the ground,
that will be submitted to the Federal Emergency Management Agency
(FEMA). FEMA will use this data along with other data collected
in the field to update the County's Digital Flood Insurance Rate
Map (DFIRM). This maps is used by insurers to determine if
flood insurance is need and is also used by the county for building
and subdivision permits. This is not the only use for LIDAR data,
the April issue of GEOWORLD magazine explains how LIDAR is being
used for Natural-Resource and Agricultural Management. Click
on the picture to the right for a link to the online article.
Interactive Mapping Application
Click here for the Interactive Mapping Application
Please visit our downloads page and click on the GIS link on the left hand column for a complete list of the available GIS downloads.