University of Wisconsin–Madison

Wisconsin Geospatial News

Project update: Version 1 Statewide Parcel Map

As part of the Statewide Parcel Map Initiative, the State Cartographer’s Office (SCO) and Wisconsin Department of Administration (DOA) are making progress on the Version 1 Statewide Parcel Database Project (V1), the first cycle of development in achieving a sustainable parcel layer as directed by Wisconsin’s Act 20. The SCO technical team has finalized a 41-attribute schema and successfully assembled portions of the V1 statewide parcel layer, working toward the July 31st completion date, when the final V1 database will be available online.

Understanding County Parcel Data

The V1 project team requested parcel and tax roll data from county land information offices on October 23rd, 2014 and are thankful to have received 100% participation. Since then, the team has been assessing the data and conducting research on how to improve the parcel data request cycle. The forum to “Align County Surveying and Parcel Mapping Efforts in Wisconsin” on March 12 at UW-Stevens Point was one step in helping the V1 team better understand the goals and concerns of professional surveyors, GIS professionals, and land information officers.

Centrality of Tax Roll Data

The development of the V1 parcel layer is largely centered on the statutorily-defined attributes, many of which represent property tax data. By statute (s. 59.72(2)(a)), nine attributes are required for inclusion in the parcel layer:

1. Assessed value of land

2. Assessed value of improvements

3. Total assessed value

4. Class of property, as specified in s. 70.32 (2) (a)

5. Estimated fair market value

6. Total property tax

7. Any zoning information maintained by the county

8. Any property address information maintained by the county

9. Any acreage information maintained by the county

Of these nine attributes, the first six are specific to municipal or jurisdictional tax rolls. After some analysis of the V1 data, the project team has been learning about the various tax roll data and GIS parcel data workflows and update cycles.

Initial Observations

Missing Data. Through assessment of the V1 data, it has been observed that approximately 20% of attributes required by Act 20 are not present. Of the 80% of attributes provided, 44% reside within the GIS parcel layer. Therefore, about 56% of required tax roll information is either not available or available only in the tax roll.

Tax Roll Cycle. County tax roll cycles are driven by the annual property tax assessment schedule. Based on this schedule, the most ideal time to request tax roll data occurs at the beginning of the calendar year. In the future, requesting parcel data in-sync with this cycle will ensure submission of the most current data available.

Department of Revenue’s XML Standard. DOR has prepared an XML standard for submission of tax roll data. A total of 17 counties have successfully submitted their tax rolls to DOR in the XML standard, while 26 others submit through .txt or other formats. DOA and the SCO have been working with DOR, with the goal of reducing redundancy in county data requests.

On the Horizon

A V1 interim project report will be provided to DOA on June 30th 2015, when the complete V1 layer will also be delivered to DOA. The interim report will feature recommendations on “benchmarks” for county parcel data improvement though Wisconsin Land Information Program Strategic Initiative grants, which will be available in 2016.