GIS/IT Department

The Jo Daviess County Geographic Information System (GIS) was established in 1999 and Information Technology was added to the department in 2006. The office provides GIS and Information Technology services and support to all County departments and provides GIS products and services to the general public as well.

What is GIS?  “GIS is an integrated system of computer hardware, software, and trained personnel linking topographic, demographic, utility, facility, image and other resource data that is geographically referenced.” NASA.  A GIS allows features of a map to be related to attribute information in a database, resulting in "intelligent maps."  

There are four major components of a GIS: (1) hardware - such as computer workstations, servers, printers, plotters, scanners, and GPS receivers; (2) software - Intergraph, ESRI, & MapInfo being three of the leading software companies in the industry; (3) users - ranging from County staff who use the system on a daily basis to the citizen who wants a map of his/her property; (4) data - the core of GIS, is developed from a wide variety of sources.  The Jo Daviess County GIS has multiple data sets including digital orthophotography, parcel ownership boundaries, road and street centerlines, topographic contours, soils, political boundaries, and taxing districts.

County employees and officials use the GIS in daily activities and through the decision-making process.  The system also provides products and services to users in both the private and public sectors.  Most commonly requested products are parcel maps, GIS website subscriptions, county maps, address atlases, and digital data.  These products and services are listed in more detail in the GIS cost recovery policy.  This policy was put in place to help maintain and continue developing the system. 

The department also posts and updates information on the Jo Daviess County website.

Jo Daviess County GIS Products, Services, & Fees
The Jo Daviess County GIS/IT Department can provide a wide variety of maps, geospatial analysis data reports, and other services. 

Available GIS products and services

Online GIS product/service request form


GIS Hardware

A dedicated server stores the GIS data and hosts the GIS online website.  Other servers also store a variety of data used by GIS/IT Staff.


Also in the office is a wide format inkjet plotter/scanner/copier.  This device can print high quality color or black & white maps up to 36" wide and it has the ability to scan documents up to 36" wide.  The County Recorder's Office also uses this device for scanning large plats.


 The hardware used in the County's Geographic Information System are the physical devices, cabling and network backbone equipment allowing the system to function. Five (5) computer workstations are used by GIS/IT Staff.


A multifunction color laser printer/scanner/copier is shared on the computer network between the GIS/IT Department and the Chief County Assessment Office. This device allows for high quality color or black & white printing, scanning and copying.

GIS Software


GIS software allows the user to interact with the GIS data.  The software resides on computer workstations and a dedicated server.

The GIS software provides the functions and tools needed to develop, analyze, store, present, and maintain GIS data. A database management system (DBMS) and an easy-to-use graphical user interface (GUI) are part of the software programs.

The County GIS/IT Department uses software developed by the Intergraph Corporation called GeoMedia, GeoMedia Professional, and GeoMedia WebMap. GeoMedia is designed for end-users, allowing data to be analyzed and presented. GeoMedia Professional is a step-up from GeoMedia and it allows for data creation and maintenance in addition to data analysis and presentation capabilities. The GeoMedia WebMap software allows GIS data to be accessible via a web browser. 

The GeoMedia software used by the County GIS/IT Department is compatible with most GIS vector data formats used in the industry today, including: ESRI, MapInfo, AutoCAD, and Microstation. The software also displays the most commonly used raster data formats including: TIF, GeoTIF, and MrSID.
GIS Users

A GIS user is anyone who uses the system or products derived from the system (such as maps or reports) to solve a question or problem.  Jo Daviess County has five full-time GIS/IT professionals who develop, maintain, analyze, and present geographic information and also provide IT support. 
Almost all County Departments and Offices have GIS users at various skill levels, including: the Office of the County Administrator, Planning & Development Office, Animal Control Office, Chief County Assessment Office, County Clerk/Recorder's Office, Health Department, Highway Department, Sheriff's Office, and the State's Attorney Office.  The Jo Daviess County Board and Planning Commission/Zoning Board of Appeals use the GIS at monthly meetings.

Other users of the system include: other local government entities in Jo Daviess County,  Illinois Department of Transportation, real estate agencies, title companies, conservation organizations, appraisers, engineers, and citizens (to name a few).
GIS Data

Nearly 80% of information housed in government is geographic in some way. In order for Jo Daviess County officials and employees, as well as the general Public, to make informed and accurate decisions, all geographic information involved with a certain area must be known and understood. Efficient and accurate development, maintenance, and presentation of this geographic data is what GIS is all about.

GIS data is derived from a wide variety of formats, including: hard copy maps, images, CAD files, spreadsheets, databases, and proprietary digital data formats. Data with limited accuracy is usually available for free or at a minimum charge whereas very accurate data can be quite costly. Choosing the appropriate data to be used for a specific project depends on the accuracy required.

Spatial GIS data are stored in two formats: raster or vector.

Raster data is a cellular data structure composed of rows and columns for storing images. Each block or cell of information is called a "pixel." Raster data includes such things as scanned aerial photographs, digital orthophotography, satellite images, and scanned documents.


Orthophotography in a raster data format.

Vector data are features defined by x,y (and sometimes 'z') locations on a grid which the software connects to produce points, lines, or polygons. Vector data includes features like parcel boundaries, road centerlines, topographic contour intervals, and address locations.


Vector data displaying subdivision lots, golf courses, roads, and text.

Tabular data are attributes describing a specific feature in the GIS. For example, a road centerline feature in the GIS could have attributes describing the road's name, jurisdiction, pavement type, and right-of-way width. Tabular data is stored in a database. It can be derived from spreadsheets, documents, and hard copy files of information.


Tabular data showing attributes of a road centerline feature.