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GIS: County Tax Assessment with GIS
Investment in a GIS proved invaluable when Kane County, III. was declared a Federal Disaster Area.
By Susan Smith When Kane County, Illinois, was hit with fierce storms that dumped 17 inches of rain within 24 hours last July, one township of approximately 36 square miles was badly flooded. Residents awoke to water-filled yards, basements and rooms, and some roads were impassable except by boat. Some families had to evacuate their homes. A few days later, President Clinton declared Kane, along with 12 other northern Illinois counties, a Federal Disaster Area.
Subsequently, the Kane County Supervisor of Assessments office (SOA) instituted a reassessment procedure for flood-damaged properties.
Those who owned property damaged by the flood applied to the County Supervisor of Assessments office to have their property reassessed for tax purposes. Fortunately, the Kane County SOA already had a digital cadastral base. They added a Disaster Area Reassessment screen on their mainframe, and cracked open the boxes of new geoengineering software, MicroStation GeoGraphics, which they purchased from Bentley Systems Inc. A federal disaster was as good a reason as any to try out the new software. So they were prepared for the lengthy process of reassessing land parcels for damage done by a flood-creating polygons for each affected parcel for their relational database.
Historically, the Kane County SOA is ahead of its time. Most county tax assessment offices are still not using computers in their assessment procedure, let alone a full-fledged GIS. "There are quite a few counties out there that do it this way (mylar maps) because of the large expense of converting to a digital format," explains Tom Nicoski, systems administrator for the Supervisor of Assessments office.
The Kane County SOA team working on the GIS/mapping portion of the special flood re-assessment project consists of Nicoski, Supervisor of Assessments Sallie J. Huber, and systems specialists Don Clayton and Stephen Dieke.
Since 1985, Kane County has been going digital. "Each year we build parcels with parcel numbers, and we delete and retire old ones," says Nicoski. "We've got all the maps in digital format." The parcel base is an inventory of all ownership in the county. Savings
Time and manpower savings are often difficult to quantify, especially when a system has gone through as many changes as the Kane County SOA system. Huber warns that creating a system such as theirs is not an overnight project. "The learning curve for your staff has to be taken into consideration." For those starting a GIS, she concludes, "you're not going to have the productivity we have now. We have it now because of the experience of our staff."
However, last year Huber ran a time study test to see just how much time was saved using a GIS. A manual technician and a computer technician both worked on the same subdivision project. It took the computer technician only six hours to complete the project, while it took the manual technician 11 hours. With the way the county has grown in recent years, "I would have had to at least doubled the mapping staff had we not had the GIS that we have in place today," says Huber.
To further her point, Huber explains that in 1985 they recorded 59 subdivisions and last year recorded 169. "I had four map techs and one clerical when we were manual," she says. "Now I have five map techs and two clerical staff. You can save on personnel-we're living proof that this does happen."
This achievement has been a long time in the making. In 1985, the Sidwell Company of West Chicago, was responsible for setting up the project for Kane County while they were still using mylar maps. Between 1985 and 1990, the SOA paid for online services with Sidwell, using their computers, until they got funding for their own technical department. This arrangement with Sidwell cost a quarter of a million dollars, says Huber. "As soon as the county committed funds to hardware and software purchasing, I took us off-line immediately, and as soon as we got our software we were able to start production, with people already trained."
In all fairness, Huber says, Sidwell agreed with the SOA's decision to bring their mapping in-house. Based on experience, Huber's words of wisdom are a warning to agencies to get a commitment for funding and get the conversion done while you have the funding. Otherwise, you risk losing funding if there's a political change. "They aren't going to want to support the project that was started by the other guys," she warns.
When Kane got the approval to go with computerized mapping, Sidwell handled all the conversions. As each township was completed, that township was turned completely over to the SOA office. Sidwell continues to do marketing and reproduction of the maps and has written third-party software, called CIDBase, to help the SOA office update their maps more efficiently.
"I'm trying to get other county offices aware of the potential use of this GIS in their areas," says Sallie Huber. Other offices, such as the sheriff's department and school district, can use the SOA's base maps and overlay them with their own information. Tools
As long-time Bentley customers, Kane County's SOA office has recently purchased 30 seats of MicroStation Image Manager, 10 MicroStation GeoGraphics upgrades, and one MicroStation Descartes license. MicroStation 95 and MicroStation Review had already been installed on 30 seats.
The office is using Pentium 90 DTK computers with 32 Mb RAM, Windows 95, with minimal hard drives since they are running everything over a Novell 3.11 network, with a 10 Mb Ethernet card. The DTKs are outfitted with ATI Graphics 64-bit Pro Turbo PCI boards. Most users have 15 -inch or 17-inch NEC monitors.
The Sidwell Company's CIDBase, software based on the MicroStation Development Language (MDL), allows the user to key in a parcel number, locate it in its design file, then window around that parcel. It also interfaces with other programs which pull up information from an external database and transfer it to this program. The program accomplishes this through database linkages.
Besides their cadastral database, the Kane County SOA office is developing a relational database which will house all their tax assessment, or attribute, information, all of which currently resides on a mainframe. They are working on an MDL application that will be useful in some of the special projects.
"We created polygons to track where the reassessment applications were coming from," explains Clayton. This way, a person on a high piece of ground would not be allowed a reassessment, since there was no way his land could have suffered flood damage.
The SOA office still has a 3270 emulation screen that shows mainframe information onscreen. By clicking on an element that represents a land parcel, users can bring up the attribute information from the Microsoft SQL Server database on a Windows NT platform.
Productivity has increased with the introduction of better hardware and software releases, plus the increased awareness of the technical staff.
MicroStation GeoGraphics and MicroStation Descartes, currently being used by Nicoski, Clayton and Dieke, will be placed in production soon. This is another step forward for the Kane County SOA, and they are already enjoying some of the benefits of a new, full-fledged GIS. "Once we go with polygons for each ownership," says Nicoski. "The Mapping Department is going to maintain it, so they need MicroStation GeoGraphics in order to do that."
Just this last year, the Kane County SOA finished all the linkages for each parcel group which would allow them to link to external databases. The Process
With the tools in place, Don Clayton and Stephen Dieke began the process of reassessing the land parcels damaged by the flood. They are using the geoengineering system to track each individual parcel on the cadastral-based mapping system. After they create polygons for each parcel, a new design file is created to track the flooded parcels. The corresponding map files are then referenced into the design file so a polygon can be drawn over the top of the existing map without changing the production design files. MicroStation GeoGraphics' topology cleanup tools are used to find and repair gaps, dangles and other geometric problems.
After all of the polygons have been created, the various maps created from the polygons can be used to analyze the flood damage throughout the county.
Before implementing MicroStation GeoGraphics, the SOA built the polygons one point at a time. "MicroStation GeoGraphics goes out and does it automatically for you," says Nicoski.
Don Clayton is also enthusiastic. "Once we do the whole cadastral base, I see it (MicroStation GeoGraphics) as a big time-saving tool." Not only will it save time in the production of polygons, but the GIS is more accurate than using manual methods. Clayton also expects it will be useful in the cleanup of polygons after they have been created.
The addition of digital ortho photography to the project adds another dimension to the images. Within three years, the county plans to get digital ortho photography for all 16 townships in the county. Photography for five of those townships has just been received and is being registered to the maps by the Sidwell Company.
"Every three years we will redo the whole county," says Huber. With Kane County's proximity to Chicago's Cook County, Kane is growing by leaps and bounds, and constantly changing.
The Sidwell Company has two aircraft providing two different scales of photography, high flight, covering a broad area at 2 foot pixel resolutions; and low flight, which focuses on the urbanized areas, taken at 1/2 pixel resolution. Software from Zeiss in Germany and ISM of Vancouver is used for making corrections and resampling the digital images.
The photos Kane SOA has posted on the Internet are actually scanned photos of each subdivision, taken around 1993. The Kane County Development Department also took some photos of the flooded County which are posted on the Internet. Interaction with Other Agencies
The SOA's contiguous database is a resource much coveted by other agencies. Because of lack of funding, the database was not completed until two years ago. "We have a few inter-governmental agreements with a few of our cities that use our database for sewers, electrical, etc.," says Nicoski. "But the areas hit hardest by the flood currently don't have inter-governmental agreements with us for that database."
The Kane County Development Department, which handles a lot of planning projects, is probably the largest user of the SOA database. Tim Mescher, GIS mapping coordinator for the Kane County Development Department, says they have quite a few additional layers of their own information which they put over the base. "We use base information such as parcel lines, plot lines, road right-of-way, for all kinds of maps we use up here," he explains. The Development Department deals with property owned by forest preserve and municipal park districts, plus land-use categories. All the districts are in the database, and layers can be created as needed.
Sharing a common system is an ideal that not many local governments and agencies have been able to achieve to date. The agreements between governments, in addition to the limitations of CAD and GIS software, have made this relationship nearly impossible.
One of Sallie Huber's many projects is to share information with other municipalities. Currently, she serves as supervisor of assessments and GIS manager. She believes that in order to extend the user base, particularly in view of the county's growth rate, the county needs to set up a separate department for GIS with its own department head.
Besides sharing data with other agencies, Huber has plans to share information with township assessors: Provide them with a map base and they can provide their appraisal base. In addition, in the coming year she will be researching field software and hardware for township assessors, whose primary function is to locate and identify property. The Future
Kane County SOA is proud of their complete digital database, something most assessment offices do not yet have. And soon, by using MicroStation GeoGraphics with their attribute data and the cadastral base, they will be able to do spatial analysis. For example, they will be able to highlight certain polygons such as all properties within a given price range.
Kane County SOA is charged with the task of convincing the rest of the county of what they know-that geoengineering, although a long time in the making, has saved them countless hours, manpower and money. Says Sallie Huber, "We have more than doubled production with fewer people. It is controlled growth-good for taxpayers and good for the county." About the Author:
Susan Smith is an editorial consultant and writer, and former editor of MicroStation Manager magazine. She can be reached at [email protected] or 505-989-4947. More details and images on the Kane County SOA project can be found on their Web site, www.inil.com/users/kanesoa/
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