Cadastral Information For GIS Specialists

Part Two - Cadastral Information

Using Cadastral Data In A GIS

- The Case of the Misplaced Boundary Marker -

Note: The following case is real.  We have purposely left out references to the actual agency and location, because, as you will see, the situation was legally sensitive.

A public land management agency used geographic coordinates from a GIS as the basis for posting a boundary along one side of an area of public land.  What they did not know at the time was that the GIS coordinates were off by 400 feet.  The true boundary extended 400 feet farther into what was thought to be adjacent private land.  So, in effect, the public agency’s boundary marker gave the impression that there was more adjacent private land than there really was.  And here’s what followed.

The person who owned the land adjacent to the public land took a look at the boundary marker and decided something like this, “Well, there’s the boundary of the public land, and that’s the boundary of my property from this side.  So I’ll put up a fence along the boundary, marking my land.”  The land owner went ahead and put up a fence along the boundary marker.  The result was that the fence, erected at the landowner’s expense, was placed on what was actually public land.  But the situation became even more involved.

The land owner then built a new home on his land, set back a few hundred feet from the incorrect boundary, no doubt thinking that the building site was a nice set-back from the public land.  It was not until after the fence had been erected and the home had been built that it was discovered that the public agency boundary marker was in the wrong place and really should have been placed 400 feet further into what was thought to be the neighboring private land.  And to make matters worse, it turned out that the new home that was built on the private land had been set back exactly 400 feet from the erroneous boundary marker, and in fact the true boundary was then found to run right through where the new home stood.  You can imagine the trouble and complications arising from this situation for the public agency and for the private land owner – having then to decide how to correct the error and what to do about the new fence and the new home – trouble arising from using GIS data as a basis for marking a boundary.

When it comes to cadastral data, always go to the legal record before making decisions.

Go on to Part Two: Using Cadastral Data In A GIS - Data Reliability at the Canyon Of The Ancients National Monument

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Table Of Contents - Cadastral Information For GIS Specialists

Links to the other Cadastral Courses:
Learning The Cadastral Data Content Standard
County Recorders And The Cadastral Data Content Standard
Surveyors And The Cadastral Data Content Standard

Presented by the United States Department of the Interior Bureau of Land Management, and

the Federal Geographic Data Committee Cadastral Subcommittee