Workshop Notes
GIS for local Government - EWCRC April 1, 1999

GIS for local Governments - EWCRC April 1, 1999

On Thursday, April, 1999 the Eastern Will County Regional Council hosted a workshop abut Geographic Information Systems (GIS) for local governments. This was a very interesting and informative presentation by Jason Morrison the Will County GIS Manager and Ron Hodgen of Ruettiger, Tonelli & Accosicates. The presentation was done in two parts: Introduction to GIS and Histroy of Will County GIS.


WILL County Geographic Information Systems

Presented By:
Jason Morrison Will County GIS Manager
Ron Hodgen Ruettiger, Tonelli & Associates

Overview:
What is GIS? Explanation of the technology
Applications of GIS: how it is being used and the ways it can be used
GIS projects in Will County
Implementing a GIS system in Local Government
Demonstration

Definition of GIS:

  • An organized collection of computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyze, and display all forms of geographically referenced information. IT IS A SYSTEM

  • A computer system capable of holding and using data describing places on the earth: a database management system.

  • A GIS creates "smart-applets": maps, or tables, or applications that are produced as the result of a query of a database. Maps or data that display answers to questions.

  • GIS software contains a set of tools for visualizing, exploring, editing, and analyzing information linked to geographic locations

  • A GIS is NOT a mapping system
  • A GIS is NOT a design tool
  • A GIS is NOT a display tool

  • A GIS IS an analytical tool
  • A GIS IS a problem solver

  • A GIS answers questions

GIS uses Database Information:

GIS Data Structure:

The Layering of Geographic Data:

Questions a GIS can Answer:

· Location: what is at_?

_ The first of these questions seeks to find out what exists at a particular location. A location can be described in many ways using: a place name, a postal or zip code, or a geographic reference such as latitude and longitude.

· 2. Condition: where is at_?

_ Where certain conditions are satisfied.

_ Example: Find all the unforested land at least 2,000 sq. meters in size that do not border a road or is crossed by a stream of more that 25 meters wide.

· 3. Trends: what has changed since_?

_ finding the differences within an area over time.

_ Example: Display the areas where cancer rates are highest_lowest_how has this changed over the past 10 years.

· 4. Patterns: what spatial patterns exist...?

_ This question is more sophisticated. You might ask this question to determine whether cancer is a major cause of death among residents near a nuclear power station. Just as important, you might want to know how many anomalies there are that don't fit the pattern and where they are located.

· 5. Modeling: what if_?

_ What if a new stop sign is added to a road network

_ "What if .." new street was added to the road network - how would this affect emergency response times. Answering this type of question requires geographic as well as other information.

Applications of GIS:

· Emergency Dispatch: routing for police, fire and ambulance_businesses such as UPS, American Airborne, and Federal Express.

· Site Selection: deciding where to set up a facility, business, or service.

· Boundary Determination: school districts, tax districts, arbitrary boundaries such as sales boundaries.

· Planning: allocating resources for road/highway maintenance, emergency planning, taxing.

· Land Parcel Information: tax assessment

· Water and Sewer (utility departments or utility companies): determining flows, pipe breaks, outages, new service, and planning new development

· Digital Data Warehousing: data is being used while being stored-data management system.

· Community Involvement: Internet

Examples of GIS Output:

· Digital Orthophoto Imagery (Aerial Photography).

· Layered information: layered information can include topography, utility, parcel and/or zoning information which can be produced as tables or maps.

· Examples...

 

Digital Orthophoto Quad

Elevations

Parcel Information: Building Footprints

The Need for GIS:

· Geography (and the data describing it) is part of our everyday world.

· Almost every decision we make is constrained, influenced, or dictated by some fact of geography.

· Example: sending fire trucks to fires by the fastest available routes.

· Governments often award grants to local governments based on population.

· We study disease by identifying areas of prevalence and rate of spread.

GIS projects in Will County:

· Supervisor of Assessment: Cadastral (Parcel) Information - tax assessment

· Land-use: Planning, Engineering, Zoning

· Emergency 911: Dispatch

· County Clerk: Census 2000

· Other Departments using: Forest Preserve District, Recorder of Deeds

Implementing a Successful GIS System in Local Government:

· Partnerships may be the key

· Implementing the right hardware and software systems

· Most important factor: personnel

· Cooperation between Departments

Cooperation and Support of Policy Makers

Cost Overview:

Things to be considered for costs:

_ Consulting: GIS work by consulting firms

_ Hardware costs: computer equipment, networks, media storage, etc.

_ Software: GIS applications

Training: seminars, users groups, conferences


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History of Will county GIS

Early 1990's
  • Many County offices were manually preparing and maintaining multiple maps at multiple scales
  • Mapping prepared separately by Tax Mapping, Planning, Zoning and County Clerk offices
  • County recognized the need for a unified digital mapping program to create a single county map to serve all purposes

Mid 1990's

  • County hires consultant to prepare GIS needs assessment and GIS implementation plan
  • GIS plan specified a three phase mapping program

Phase I - Survey Control:

  • GPS monuments set at 3 mile grid across county
  • Accessible section corners recovered
  • County benchmarks recovered

Phase II - Aerial Photography:

  • Digital photography/orthophotography
  • High altitude flight for entire county (May 1997)
  • Low altitude flight for urban areas (May 1997)
  • Two sets of digital orthophoto files
  • Digital topography (2' contours)
  • Digital files delivered 1998 through 1999
  • All monuments were surveyed via GPS with accuracy at +/- 1 inch
  • Phase 1 completed in 1998

Phase III - Digital Parcel Mapping

  • Digital parcel mapping by digitizing existing tax maps and subdivision plats, using orthophotography asan overlay
  • GIS parcel database based on PIN
  • Deliverables June 1999 through January 2000

Near Future:

  • County GIS department to update GIS parcel mapping and database files
  • Data to be delivered to the used by other departments
  • Additional datasets to be added to the GIS for further functionality

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