There are four feature datasets in the Parcel Data Model Template: Basemap, Cadastral Reference, TaxParcels, and AssessmentInformation. This blog entry describes the Basemap and Cadastral feature datasets and provides you with some tips on using them with your data.

Basemap Feature DatasetBasemap in Template Geodatabase

The Basemap feature dataset contains reference information that adds geographic context to tax parcel information. The feature classes in this dataset are used to produce the Map Documents (MXDs) and online basemaps provided in the template downloads. Data for some of these feature classes may not exist in your organization, or at a minimum, may be structured differently. Furthermore, if you’re an assessing agency, this information will most likely be provided by other GIS data producers in your organization. That’s okay, just take a close look at the ground control used for the basemap information; you’ll want to ensure it’s consistent with the ground control you use (or plan on using) for your tax parcel geodatabase.

If you are planning on using the MXDs provided with each template, you may want to review the HTML documents provided in each template’s documentation folder to make the migration of your basemap data easier. The cartography and label expressions in each of the MXDs require certain fields and/or values to be present in the data. If you don’t have this data, or if it’s structured differently, you’ll have to spend some time repairing the MXDs so they work with your data. If you don’t intend on using the MXDs provided with each template, or have other plans for your system, you can remove the Basemap feature classes and use something different you may have.

Paste Failed ErrorIn general, you should be able to import or copy/paste most of the basemap data into your target geodatabase. If you get an error like this one when you copy/paste your basemap data into the geodatabase, you may want to import the feature classes instead. This error is due to some subtle differences in the properties of the target feature dataset/spatial reference and should not be a concern.

Cadastral Reference Feature Dataset

Throughout most of the State of Michigan, the Public Land Survey System (PLSS) serves as the cadastral framework and is used to survey and identify land parcels. The Cadastral Reference feature dataset contains the nested components of the PLSS framework used for tax parcel mapping. These nested components are described in more detail in the book published by ESRI Press called GIS and Land Records.

Cadastral Feature Class in GeodatabaseThe cadastral reference features are modeled separately because they are not typically maintained by the same agency that is responsible for tax mapping. And while they are modeled separately, it’s important to note that they are spatially related to the features contained in the TaxParcel feature dataset and an integral part of the tax parcel maintenance workflow.

Like the data contained in the Basemap feature dataset, this data may be structured differently (or you may not even be a PLSS state) in your community. If it is, that’s okay; you can just delete the feature classes in this feature dataset and import your own cadastral reference data. Just ensure your cadastral reference data is spatially coincident with your tax parcel data and that you have a plan to ensure it remains that way going forward. If you don’t have the features contained in this feature dataset, or are just starting your automation/conversion project, then this is probably the first place you should start your project. Establishing a strategy for ground control and the cadastral reference up front will save you buckets of time and plenty of headaches in the future.

Check out the next blog entry for information about the TaxParcels and AssessmentInformation feature datasets.

The ArcGIS Land Records Team