Cadastral Data and Base Map/Georeferenced Tile package Not matching up – February 24, 2023 at 03:17PM

Hey there – long time lurker, first time poster. Love what you do, just love it.

I have an issue with data sources not agreeing. I am using the cadastral data provided by BLM map services and an authoritative tile package created from the FSTopo public map service.

https://gis.blm.gov/arcgis/rest/services/Cadastral/BLM_Natl_PLSS_CadNSDI/MapServer&https://www.arcgis.com/home/item.html?id=df307ec1e488406ca54eb1ccd27e14d7

For whatever reason, there is a nonuniform discrepancy between the section lines from the map service and section lines depicted in the tile package. The discrepancy is sometimes as great as 230 meters. To further complicate issues, the tile package appears to line up perfectly with Esri Base Maps like USA_Topo_Maps.

Purple is map service PLSS and red are the PLSS from the tile package

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Purple is map service PLSS and red are the PLSS from the tile package and the USA_TOPO_Maps base map from Esri

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Tile Package and USA_TOPO_Maps base map with nearly coincidental PLSS section boundaries

So what’s up with that?

While the PLSS can change over time, is it fair to assume that the tile package was georeferenced using Esri Base Imagery and that’s why those two match up so well?

And if that is the case, then I assume that he BLM map service depicting PLSS boundaries is more accurate than the boundaries shown in the tile package. Is that a fair assumption?

Thanks in advance!

*edited 20230224 to add images