Why is it that some of the worst movies produce lines that stick in our heads forever after? And what was Sean Connery thinking when he signed on for Highlander? And why do I have “there can be only one” running through my head in a Scottish accent? Well, why not turn it into a metaphor for base mapping data management!
There can be only one.
Ideally, that is. The importance of a single, maintained base mapping layer in your enterprise GIS really can’t be understated. This layer controls all the others, and in doing so, drives the accuracy and currency that will propagate through the rest of your data, and your organization. This layer contains the land survey data. In the WhiteStar world, these are the Public Land Survey Data and the original Texas Land Surveys.
This layer contains both data that has been digitized from source documents, and, increasingly, GPS coordinates of on-the-ground survey monuments. As each GPS point is incorporated into the dataset, it improves the overall accuracy of the fundamental base layer.
The other layers are then rectified and improved as this new, additional information becomes available. By approaching it this way, survey data finds a “home” in the enterprise GIS system, rather than being scattered about in isolated point data files – and the dataset as a whole benefits.
Each of these points comes with some rich metadata, such as source, accuracy, and even, in some cases, photography of the individual monument. As the points are incorporated, the land survey network lines are updated to include the GPS coordinate, and then other (less accurate) layers are conflated to it, resulting in accuracy improvements across the board.
Part of this process is fitting the Land Parcel data to the base, with no gaps or overlaps. Queries like “show me on the tax parcels in township 53N 69W” will only be answered accurately if the underlying data is perfectly clean. The same adjustments apply to supplementary datasets like county lines, ownership layers, parks, forests, and military boundaries – and add value to data along the way.
“There can be only one” is our approach to base mapping data management, and it produces the highest quality and most accurate datasets possible – and that accuracy can be the basis of better business decisions for you.
And in case you weren’t around in 1986, and have no idea at all what Highlander is, here’s the trailer!