Geographic Resource Solutions

The objective of this project was the update and correction of the existing Placer County Assessor’s Parcel Database. The parcel data had been converted based on 1997 Assessor’s maps records and was both out of date and in need of correction.  In addition, the 279 separate AutoCAD dwg files were not capable of being used in a GIS for spatial analysis or query.

GRS developed routines and GIS data structures that allowed for the seamless translation between CAD and ArcInfo formats. CAD standards and specifications were developed and implemented by GRS to eliminate erroneous layer, size, and color characteristics.  GRS performed over 1600 parcel updates provided as either registered or unregistered AutoCAD files. Updates and corrections were integrated into the existing CAD files. Parcel data were COGOed, as necessary to perform corrections and updates.  GRS implemented a topology validation process that would not comprimise the accuracy of the data (the ArcInfo ‘clean’ command would have degraded the data).  The 279 validated CAD files were then merged and edge matched to form a seamless parcel database in the GIS.

GRS developed and implemented a method for storing over 2,500 condominium on up to seven different levels in the parcel database.  In addition, GRS created over 2,000 undivided interest parcels in the database to accurately portray those County parcels of split ownership.

This project also included the reconciliation of over 4,000 mismatches between the GIS Parcel database and the master APN database.