Four years and $50 million after enacting the Statewide Land Information System in Wisconsin, the state Legislature asked to see some tangible benefits from the enterprise. In response, the State Land Information Board pointed to Winnebago County, one of the first to develop a GIS-based land information system (LIS). In the process of developing the countywide system, Winnebago created a floodplain-boundary profile far more accurate than the existing Flood Insurance-Rate Maps (FIRMs) required by the Federal Emergency Management Agency (FEMA). FIRMs are used by the county and by mortgage lenders to identify buildings within the floodplain. Owners of such buildings must conform to floodplain zoning ordinances and carry expensive flood insurance. The new profile shows
that more than 2,000 buildings on the old FIRM are actually out of the floodplain.
FEMA approval of the new Winnebago County floodplain-boundary profile will mean millions in flood-insurance savings and increases in property values for the affected homeowners and businesses. It will eliminate the need for property owners incorrectly shown on existing FIRMs as on the floodplain, to go through the expensive process of proving they are not. It will also result in the adoption by FEMA of more accurate FIRMs.
Winnebago's LIS is the result of a four-year, coordinated effort by seven municipalities to modernize land- and infrastructure-management needs of city and county agencies, and enable government, utilities, and private enterprise to share specific data resources via an open software environment. The system is expected to increase government efficiency and public service by eliminating duplication of land-record operations and standardizing data storage management. Also it will enable county zoning to expedite evaluation of land-use restrictions, and give taxpayers access to property-tax information via the Web.
One-Third in Floodplains
Winnebago County is in east-central Wisconsin, along the western shore of Lake Winnebago, the largest lake in the state. According to 1998 Census estimates, the population is 154,000, mainly centered around Oshkosh, the county seat, and near the towns of Neenah and Menasha. Nearly a third of the county's 500 square miles -- including Lake Winnebago, two smaller lakes, the Fox and the Wolf rivers, and numerous streams -- are floodplains. Rain and snow together annually average 30 inches, and in the past, heavy rains have caused flooding in certain areas of the county.
Until development of the Winnebago LIS, federal and state law required the county to base floodplain zoning ordinances on FIRMs produced by FEMA. Where and how new structures could be built depended on whether the FIRM showed the building to be in or out of a floodplain. Mortgage lenders used FIRMs to require flood insurance on buildings in flood-prone areas, to reduce the need for disaster assistance when devastating floods occurs. However, County Zoning Administrator Robert Braun said the Zoning Office is now using the new map developed by the Wisconsin Department of Natural Resources (WDNR) to determine the location of buildings, relative to a floodplain.
The Problem with FIRMs
Braun pointed out that the old FEMA maps were drawn at a scale that makes locating a property virtually impossible. "There's no way to get parcel specific at 1:24,000 [1 inch = 2,000 feet]; the width of a line on a FIRM can represent as much as 50 to 100 feet, depending on how thick the ink was when it came out of the pen."
Ben Niemann, professor of urban and regional planning at the Land Information and Computer Graphics Facility at the University of Wisconsin, Madison, agreed. "FEMA uses 1:24,000 quadrangles to draw the delineation -- you're talking about contour intervals of 10 feet. It is very difficult to draw a floodplain using that scale of map, especially in Winnebago County, where the topography is so flat. Although the margin of error can be quite large, the FIRM is still the determinant of whether or not a building is in the floodplain," he said. "A resident whose