Wisconsin Geospatial News

SCO and UW-Eau Claire launch “virtual data integration” research project


Staff at the State Cartographer’s Office (SCO) at UW-Madison and the Department of Geography and Anthropology at UW-Eau Claire recently launched a research project to examine the feasibility of integrating existing county Web map services to produce an online multi-county parcel map viewer. The overall goal of our project is to investigate the feasibility of using Web map services to create a statewide view of geospatial data collected and maintained at the county level.

In other words, if a county publishes parcel data to a public web site (using ArcGIS Server or similar technology) our project investigates ways to combine that online data with similar online data from other counties.

The initial focus of our project is on parcel data because parcels are of interest to a wide range of users. However, the project has a broader purpose, namely to explore how Web map services can be used to support “virtual data integration” for simple mapping and display. The project will focus on several research questions, including:

  • How much flexibility exists to resymbolize map services from different counties?
  • What are the limitations on querying and analysis, given that data models and attributes are not consistent from county to county? 
  • How much of an issue is performance? 
  • Can both commercial and open-source services be integrated into a single Web application?

Several other projects are underway in the state that also focus on parcel data integration. Our project comes at the question from a different perspective. We are not trying to stitch together copies of local datasets into a common data model. Instead, we want to create a map viewer that simply points to existing online resources. As such we do not require copies of datasets from each county, nor do we need to define common data attributes or try to edgematch adjacent county data. Another advantage of the approach is that the resulting map viewer will point to the most up-to-date data from authoritative sources (i.e., the counties).

We know that there are some technological limitations inherent in our approach. For this reason, conventional data integration efforts will continue to be important into the near future to produce multi-county datasets. However, we anticipate that some of these technical limitations will diminish as software and user needs continue to evolve.

Our project is in the early stages. We greatly appreciate the endorsement and assistance of the LION President (Jeff DuMez) and LION Board in kicking off the project. The research team is now in the process of collecting information from county LIOs on map service URLs (Web site addresses). 

Once we have collected the necessary URLs, we plan to integrate the map services into an online map viewer, and then make the viewer available through the SCO Web site. Users will be able to map and view online parcel data, but will not be able to download the data. The purpose of our project is not to develop a statewide parcel dataset, but rather to explore the feasibility of virtual data integration as a simple way for users to view published Web map services. The end goal of our project is a Web map viewer and a brief report that lists the outcomes of our research questions. 

Given the many recent discussions that have occurred about the need for statewide datasets, we feel that this is an important approach to examine in detail. Statewide data integration continues to be an elusive target in this state. The biggest beneficiaries of integrated data may not be individual counties so much as other organizations that have a business need for regional or statewide data. Increasingly this is not just state agencies, but also scientific researchers, non-profits, regional planning commissions, economic development agencies, emergency managers, public health practitioners, and many, many others. Applications of geospatial technology have exploded in the past decade and there is tremendous demand for regional and statewide datasets for efforts that will benefit all citizens. For example, I’m sure we could all agree that developing statewide parcel data to help stimulate economic development and employment growth in Wisconsin is something that would benefit all of us.

Please contact us if you would like more information: Howard Veregin 608-262-6852; Brenda Hemstead 608-263-4371; Martin Goettl 715-836-4709