Are you involved in the effort to create a National Land Parcel Database (NLPD)? If not, you should be.

With or without surveyor involvement, the NLPD is expected to move forward. “The NLPD will eventually be a federated system of databases with potentially over 4,000 individual data stewards contributing and maintaining datasets,” says Nancy von Meyer, one of the support resources for the Federal Geospatial Data Committee (FGDC) Cadastral Subcommittee, which focuses on coordinating national cadastral, parcel and land records efforts.* “Hopefully, states will provide coordination and be a trusted source for the publication of parcel data.”

Where will that state data come from? Right now, the parcel data sets being created are “good enough” that government agencies do not feel the need (in most cases) to ask surveyors for assistance. The truth is that many surveyors will not play a role in the formation of an NLPD unless they forge the path themselves.

There are not enough funds in any one organization to survey the entire country as a single project. But as homeowners, mortgage agencies, county appraisal districts, civil engineers and others pay for surveys on an individual basis, these surveys can be applied to a “greater good”-the free and open distribution of an NLPD. Surveyors need to get “on board” with GIS for their own business reasons; beyond that, though, there is real opportunity to create an accurate, standardized database of parcels for the entire country. Such a database holds potential benefits for land surveyors as well as the general public.

Database Structure

The Federal Geospatial Data Committee (FGDC) Cadastral Subcommittee has already created standards for the publication of parcel data. The plan is for the states to assemble, integrate and publish cadastral data through a state cadastral coordinator.

There are different types of data, which could also be considered varying “data levels.” Most business applications (emergency response, mortgage crisis support, etc) are interested in “published data,” which is the final product. The states and counties work with “production data,” which are used day to day and can change often. The official published datasets are known as “trusted data;” these are created from “authoritative data,” which have been verified for accuracy and consistency and have an identified authoritative data steward.

A number of hurdles remain to the widespread adoption of the NLPD. According to Jimmy Nolan, cadastral coordinator for Georgia, two of the biggest challenges are integrating new data with legacy data and ensuring data consistency. In Georgia, for example, the state collects data from counties, and each county has its own system for creating and maintaining data. These “production data” can vary greatly in accuracy and structure. Systems will need to be put in place to regulate the data entry and integrate it into “production data.” This is where surveyors can create value. Since multiple surveyors will be entering data and surveyors do not always agree on boundary lines, then a system will need to be created to make definitive decisions. Perhaps this system could be overseen by a chief surveyor for the state. In any case, successful implementation of a common database will require some unity on the part of surveyors.

“What’s in it for Me?”

There are two main schools of thought when it comes to data distribution: 1) free and open and 2) paid. Most surveyors would prefer to get paid for submitting data to create an accurate GIS. However, supporters of the free and open plan advocate that the data will benefit everyone, including surveyors, and does not require much more effort to create on top of what is already being done, so there is no reason to charge extra for it at a basic level. In either case, being able to provide data directly to a GIS in a way that adds value will increase the overall value of the surveying profession.

For example, in King County, Wash., the process for creating data is a common one: Get a deed and plat, open the desktop GIS application (such as ArcGIS) and use a tool for mapping legal descriptions. This is a fine process for many situations, but it lacks many of the benefits that a surveyor who is entering coordinates from a field survey device or even using the same tools themselves could provide. If a surveyor goes to a site, performs his or her job, and takes an extra 10 minutes to map the data in a GIS or submit it through some type of system, and then sends those data to the county, the county has now saved time (read money) by not having to pull deeds and pay for the resources (hardware, software, peopleware) needed to map the parcel. The county would then become a center for managing data being submitted by multiple sources, making sure it adheres to certain standards of accuracy and structure and is correctly combined with “legacy” data.

The Montana Control Point Database is a great example of how survey data can be used in a GIS. Montana has a system for surveyors to upload control points. The state freely distributes cadastral and other data through an easily accessible system. Users-whether small business owners who need to find a prime location, parents looking to buy a house in the best local school district, or surveyors doing research on an area before accepting a project-all benefit from this system.

On that note, I urge you: get involved. Let’s open a dialogue on what surveyors can do to make a trusted National Land Parcel Database a reality.

For More Information

· FGDC Cadastral Subcommittee, nationalcad.org/.

· FGDC standards for the publication of parcel data, nationalcad.org/showdoclist.asp?doctype=1&navsrc=Standards.

· University of Georgia Office of Information Technology Outreach Services, www.itos.uga.edu/.

· King County, Wash., GIS Center, www.kingcounty.gov/operations/GIS.aspx.

· Montana Control Point Database, gisservice.mt.gov/MCPDviewer/ and giscoordination.mt.gov/geodetic_control/msdi.asp.

· Folger, Peter, “Issues Regarding a National Land Parcel Database,” www.fas.org/sgp/crs/misc/R40717.pdf.


Footnote:
*Nancy von Meyer will be speaking at the ESRI Survey and Engineering GIS Summit (www.esri.com/segsummit) about how surveyors can get involved in the creation of the NLPD. Be sure to follow Sight Lines and other POB blogs for continuing coverage of the SEG Summit and ESRI User Conference.



Editor's note: See the related article in the July issue of POB, Surveying GIS: The national cadastre, by Michael L. Binge, LS, GISP.