A National Parcel Polygon Service

A Nation of Parcels — Part 1

This is not a new concept. Providing or serving all the parcels in the nation in one place has been a part of the discussions since the first multipurpose cadastre discussions in the 1970’s and 80’s. David Moyer has documented a decade-by-decade history of the development of a national parcel data system that can be found here https://nationalcad.org/download/LandRecordModernizationHistory-Moyer.pdf

The national parcel polygons service is a web-based effort that would be a publicly accessible and annually updated web service seamlessly providing parcel polygons and a local parcel identifier for every parcel in the country.

• Covers the entire nation

• Has no use or access restrictions

• Can be downloaded or used as a feature service

• Provides geometry and an identifier only

• Provides a link to the data provider

• Annual updates from statewide data aggregators

This data set does not provide all the information for every parcel based in the nation. It does not provide a daily update of all land sales or define title boundaries. The concept is that the most detailed information is collected and housed in the most local government. This is where the most authoritative, legally binding, current and accurate data are kept and maintained. Many regional and state governments aggregate this local data into standardized summary data sets that support cross jurisdictional or jurisdictional comparison business needs. The state aggregated data is less detailed and less current than the local data, but more detailed than a national data set.

The national parcel polygons provide a view of the ownership patterns. The number of parcels and the geometries can be combined with other data to get a sense of the landscape or to form strategic positions. Adding the local data maintainers identifier and codes to identify the local producer make it possible to “dig deeper” to get the detail needed for more in-depth analysis and decision making.

This infographic illustrates this concept of declining detail as the coverage expands.

The national parcel polygon service is a modest effort with achievable goals. Certainly, there is additional information that could be added to a national data set. But we must start somewhere. We must prove we can assemble and maintain this data. That it can be a national and public resource. We can overcome institutional barriers combining data from multiple data stewards and sources.

We also must understand the costs, resources, and commitments necessary to provide and maintain such a service. This will take public and private resources and partnerships. Parcel providers at all levels of government must be a part of the solution.

Join me and let’s make this happen. It’s time for us to be a nation of parcels.