• The committee is not proposing a centrally maintained database. The vision is a federation of systems, all of which serve as conduits for data aggregated “virtually” at state and national levels.

  • State and federal coordinators will set and enforce standards, provide technical assistance, reconcile boundaries, coordinate and distribute funds, and act as aggregators and delivery mechanisms. They will maintain data on state and federally managed lands.

  • The federal government should assist with the costs of initial conversions as well as the incremental costs of standardization and distribution. However, ultimately, the program should follow a collaborative model and be supported by all parcel producers and users.

  • Development of nationally integrated land parcel data will be an ongoing process. Single points may be used to represent some parcels in the initial phases, to be replaced by polygon representations as they become available. Boundaries will be reconciled and accuracy improved as time goes on.

Once established, the parcel system would provide an unambiguous set of land parcel data that completely cover the United States. When attached to appropriate attributes, these parcel data would provide a clear basis for all decisions relating to land ownership and use. A by-product of this approach would be a system of accurate, current, and unambiguous geographic coordinates for all street addresses in the United States. As in many developed nations, the local government parcel database would be the definitive source for all street addresses. These geographic representations of street addresses would form the basis of a consistent emergency 911 (E911) system, as well as robust location-based services. No matter what service one used—an E911 dispatch program, a web-based map, or a vehicle navigation system—a street address would be associated with the same location on the earth. Therefore, the national parcel system would support the needs of the postal service and the Bureau of the Census as well as the average citizen and entrepreneur. The committee believes that this system could become a widely adopted and highly valued resource. Over time, various stakeholders could form an authoritative chain of transactions that would keep the system current, so that the information is timely enough to be valuable to the consumer market.


It is not feasible for a single entity to interact with the large number of counties, municipalities, regional bodies, school districts, and special districts in the United States that produce parcel data. Therefore, an intergovernmental framework involving local, state, and federal agencies would have to be established and promoted in order to develop nationally integrated land parcel data. In their article about local government data sharing, Harvey and Tulloch (2006, p. 764) characterize this type of arrangement as a “Federation by Mandate” in which

… an agency (or group of agencies) is given special authority with regard to data production and sharing. An example would be a regional planning agency that is designated by the state as the official producer of specific data layers. Their authority may extend to requiring other jurisdictions to submit data to be incorporated into the official dataset. Unlike the hub-and-spoke model, this would be a more complex network, in which many of the participants are major data producers. The mandated participation creates a significant opportunity for consistent data across a jurisdictionally complex landscape. The federation by mandate has a high reliability over time, wherein participants can generally count on the availability of the same data under roughly the same terms year after year across a fairly wide area.

Need for a Multipurpose Cadastre (NRC, 1980) recognized that organizational and institutional issues would be the major barriers to implementation of a national system of land parcel data.

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