Whitman County Parcel Mapping

Whitman County in eastern Washington is home to over 45,000 residents and contains roughly 160 square miles of land. This county was one of the last in the nation to digitize its parcel data in GIS, so the County reached out to FLO, which had also begun a similar parcel mapping project for Pullman, the county’s largest city.

The task was to build a county-wide parcel GIS layer utilizing the latest Esri tools to accurately represent the County’s parcels using legal descriptions dating back to the turn of the century. FLO addressed the challenge of maintaining topological relationships of those parcels while rectifying contradictory and inaccurate source information.

FLO developed a precise workflow that utilized coordinate geometry (COGO) to accurately capture the scanned survey information, ensuring the correct shape of each feature class polygon. Multiple staff members conducted thorough quality assurance and quality control checks before final acceptance using a multi-user enterprise geodatabase. Over 30,000 address points were geocoded and joined with spatial geometry to generate accurate address attributes. The final deliverable also integrated parcel data with the assessor's database to provide a precise GIS representation of parcel, address, and assessor information. Throughout the project, FLO collaborated closely with County assessors to resolve any issues and clarify details.

FLO delivered an extensively updated GIS dataset for over 30,000 parcels to the County. Instead of a disparate and unstructured system reliant on scanned PDF files and a non-spatial database, the County realized the inherent benefits of efficiency, accuracy, and convenience and established a solid foundation for the future with this updated GIS-based system.