A Framework for Land Records

More than 20 data models for industries, such as petroleum and telecommunications, and disciplines-such as basemap and parcel-are currently being developed by Esri in cooperation with GIS leaders across a broad spectrum of industries and disciplines. These data models can make GIS more accessible to average organizations with limited budgets by providing a practical template for implementing GIS projects for a specific application or industry. Data model templates not only speed implementation but also simplify integration of similar datasets at local, state/provincial, national, and global levels. The goal in creating data models is not establishing formal standards but benefiting real GIS projects.

While each ArcGIS data model is being developed specifically for an application or industry, in practice datasets developed using various models are used together. For example, a county may use separate data models for hydrology and transportation in addition to the parcel data model, but in a typical county government setting, these datasets would be used together. The common ArcGIS platform allows these datasets to easily work together.

The ArcGIS Land Parcel Data Model uses an open and flexible object-based data model that accommodates a wide range of applications and parcel definitions. Thematic layers in the land parcel data model, such as parcel framework, ownership and taxation, and administrative areas, are mapped to the geodatabase structure. Several layers can combine to form a set of feature classes in a feature dataset. The model also implements topology as a flexible set of integrity rules that defines the behavior of spatially related geographic features and feature classes. Users can model spatial relationships, such as adjacency, and manage the integrity of coincident geometry between feature classes (e.g., coincident exterior parcel boundaries and subdivision boundaries).

The ArcGIS Land Parcel Data Model captures the collective experience gained from more than 20 years of managing parcels using GIS technology. Nancy Von Meyer of Fairview Industries is the primary author of the data model and accompanying documentation. Scott Oppmann and the GIS project team at Oakland County, Michigan, provided significant review and testing of the model as well as a sample dataset that is available for download with other information about the data model.

Better parcel information supports local government and private sector decision making. This land parcel data model can be used as a starting point for defining parcel information in the ArcGIS environment and integrating land ownership information with other data. Applying the definitions and structure of the model will facilitate data distribution and help standardize the best practices and enable land record modernization, which will provide a solid foundation of digital land records and parcel infrastructure for the future.

Steve Gris�, Esri
Tel.: 909-793-2853, ext. 1-2494
E-mail: sgrise@esri.com
or
Wayne Hewitt, Esri
Tel.: 909-793-2853, ext. 1-2590
E-mail: whewitt@esri.com