How Wisconsin Created a Sustainable Statewide Digital Parcel Database

March 8, 2017

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Wisconsin is one of approximately ten states that have developed a statewide digital parcel database that is complete, publicly accessible, stewarded, and based on a sustainable program to ensure that the database remains up-to-date. Wisconsin’s parcel program was developed through cooperation and collaboration between state government, the University of Wisconsin, all seventy-two of Wisconsin’s county governments, and a handful of municipalities that maintain parcel data separately from the counties.

Wisconsin’s statewide parcel database is available to the public online through a mapping application and via ftp in a standardized format. The database contains attribute information for 3.4 million parcels, including the owner and address, property value and taxation, parcel size, and class of property. The database is updated once per year to incorporate changes reflected in county tax rolls. Funding for the parcel initiative helps ensure that all counties continue to participate by contributing their data in standardized formats to allow for easy data integration.

Statutory Authority

The statewide parcel database program was created by Act 20, Wisconsin’s biennial state budget for fiscal years 2014 and 2015. Act 20 authorized the Wisconsin Department of Administration to create an implementation plan for a statewide parcel database and directed Wisconsin counties to coordinate their digital parcel mapping efforts with the DOA. The goal of the statewide program is to create an accurate and continuously maintained public digital parcel database to support Wisconsin’s $460 billion in taxable real estate assets, improve governmental services, and enhance the state’s economic competitiveness.

Act 20 provided for funding of the parcel program through the existing Wisconsin Land Information Program, the mechanism that has funded county land information modernization projects in the state since 1990. The WLIP, administered by the DOA, provides funding to counties through register of deeds real estate document recording fees. A portion of these fees is retained at the county level to support land modernization efforts, while another portion is collected by the DOA and reallocated to counties in the form of base budget, educational, and strategic initiative grants. In 2016 the total amount of fees retained and granted to counties was approximately $13 million.

Data Standards

To facilitate development of the statewide parcel database, DOA contracted with the Wisconsin State Cartographer’s Office at UW-Madison. The Version 1 parcel project extended from July 1, 2014, to Sept. 30, 2015. The goal of the project was to collect county parcel datasets, integrate them to create a statewide database, and post the statewide database online. A major part of this initial effort was the development of integration methods and tools to join together disparate formats of parcel data collected from all seventy-two counties.

This diagram gives a schematic representation of the parcel integration process.

It was recognized early on that to make the integration process efficient and sustainable, there would be a need for standards for data exchange. Act 20 authorized the DOA to develop a “searchable format” for parcel data that incorporated the following attributes for each parcel: assessed value of land, assessed value of improvements, total assessed value, class of property, estimated fair market value, total property tax, zoning information, property address, and parcel acreage. Analysis of county parcel data submitted for the Version 1 project facilitated the development and specification of the searchable format schema for subsequent data submissions.

Because GIS data and software vary from county to county, the searchable format was seen as a potential barrier to participation by all counties. A flexible data submission process was desired to allow counties to continue to use existing internal workflows, with increased levels of standardization to be implemented incrementally over time. The resulting export format provides this flexibility, but is a temporary solution that will eventually be phased out as county capabilities evolve to support the searchable format.

This map shows the 3.4 million parcels in the Version 2 database.

The Version 1 statewide parcel database was made publically available online in July 2015, both through an online web application and via ftp. The Version 2 project, extending from 2015 to 2016, focused attention on efficiency and sustainability by refining data submission requirements, incorporating feedback from the community, and enhancing standardization efforts. The Version 2 database, with 3.4 million parcels, was published online in 2016. The Version 3 project, which launched in January 2017, focuses on the searchable format as a way to support asynchronous real-time publishing, whereby updates to a given county’s parcel dataset can be ingested and incorporated into the online statewide database with a minimal of manual effort.

Benchmarks, Observation Reports, and Strategic Grants

The benchmark concept was developed during the Version 1 project as a way to align county parcel mapping activities to overall statewide strategic goals. This is necessary because counties are at different stages of completion with respect to digital parcel data. Benchmarks provide a step-wise model to help ensure that data development efforts are aligned across all counties, and that WLIP funds are being used in ways that will advance the objectives of the statewide parcel program.

The four benchmarks developed for the V1 project include:

  1. Submission of county digital parcel data, including geometry, with complete attributes as required by Act 20.
  2. Submission of all county digital parcel data, including geometry, with an extended attribute set as defined in project documentation.
  3. Completion of parcel data for any parts of the county where digital parcel data is missing.
  4. Completion of Public Land Survey System modernization and integration into the parcel database.

These benchmarks reflect the specific objectives of the statewide parcel program, i.e., a parcel database that is complete, current, positionally accurate, and attribute-rich, and which can be assembled from individual county datasets quickly and efficiently.

Compliance with benchmarks is assessed via the annual county data submission process, and communicated back to counties using observation reports detailing issues that need to be addressed to ensure specific benchmarks are met in future data submissions. Benchmarks are also tied to WLIP funding, such that counties must demonstrate successful progress through benchmarks to be eligible for continued WLIP funding for the parcel program.

This figure is an example of a county observation report.

The Statewide Database

The most current parcel database, Version 2, has been available online since July 31, 2016. In addition to the statewide database containing 3.4 million parcels, individual files are also available for each of Wisconsin’s seventy-two counties. Through Jan. 18, 2017, there have been over 2200 downloads of these databases, equivalent to about 90 downloads per week.

This map shows statewide parcel database download statistics.

The statewide parcel database is also accessible via an online map application. From the release of this application on Oct. 17, 2016, through Jan. 18, 2017, there have been over 1900 pageviews, equivalent to about 140 pageviews per week. Based on domain names recorded by Google Analytics for approximately 900 pageviews, the predominant domains are .com (41%), .net (31%), various levels of government (20%), and .edu (3%).

The Future

The Wisconsin Statewide Parcel Program has been successful in meeting its objectives of providing statewide parcel data to the public. Web site statistics show a clear demand for parcel data on the part of a broad user community. State agencies and private sector businesses have reported time and cost savings for applications as diverse as real estate, utilities, forestry, wildfire mapping, and manufacturing properties assessment.

Wisconsin’s parcel program also serves as a model of successful collaboration between state government, county land information offices, and the University of Wisconsin. Future versions of the parcel project will continue to enhance the quality of the published data and focus on methods to reduce the cost and effort associated with data integration.

We wish to acknowledge the contributions of the parcel project team at the Department of Administration and State Cartographer’s Office, including our student assistants. We also wish to acknowledge the cooperation and collaboration of county Land Information Officers and other data stewards who made this project possible. 


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