Utah County Modernizes Property Assessment with GIS and AI

Utah County, Utah, is one of the fastest-growing counties in the United States. The county manages over 284,000 parcels and must review every property assessment within a five-year cycle. Rapid growth and ongoing development create a challenge for assessment staff, who must maintain accurate property records while ensuring fair and equitable taxation.

To help appraisal staff focus on the properties most likely to require reassessment, Utah County turned to the geographic information system (GIS) ArcGIS and artificial intelligence (AI) to identify potential discrepancies and prioritize assessments more efficiently. Using these technologies, the county developed an AI-assisted workflow that compares building sketches maintained by the Utah County Assessor’s Office with current building footprints identified from aerial imagery.

By integrating AI into a GIS environment, Utah County brings parcel data, aerial imagery, building sketches, and assessment records together in a single operational view. With that information available in one place, appraisal staff can focus their time and expertise on the properties most likely to require reassessment, helping them make more informed assessment decisions.

The Utah County Assessor’s Office maintains building sketches for habitable structures throughout the county. These sketches help determine taxable square footage and support accurate property valuations. As development accelerated across the county, keeping those records current became increasingly challenging.

State requirements add another layer of complexity. Utah County must review every property assessment within a five-year cycle, requiring assessors to evaluate tens of thousands of properties each year. Traditional methods relied heavily on field inspections, permit records, and manual review processes to identify additions, remodels, and other changes that could affect assessed value.

Rather than asking assessors to search for changes across thousands of properties, Utah County wanted to help staff quickly identify which parcels were most likely to require attention.

“We have a lot of properties, and it’s impossible to inspect them all manually. We’re required in the state of Utah to review every assessment every five years, so [geospatial AI] gives us a way to narrow our focus significantly,” said Patrick Wawro, information systems director for Utah County Government.

As development accelerated across the county, assessors needed a more efficient way to identify property changes that warranted additional review. Utah County’s GIS Division developed a geospatial AI workflow. Geospatial AI combines GIS and AI to analyze spatial data, identify patterns, and help staff make more informed decisions. In Utah County’s case, the workflow analyzes high-resolution aerial imagery to detect building footprints and compare them with assessment sketches maintained by the assessor’s office.

After the AI model detects building footprints, the GIS team uses ArcGIS Pro to process and analyze the results. This system compares AI-generated building outlines with assessor sketches, calculates match scores, and identifies properties that may warrant further investigation. Appraisal staff use those results to prioritize assessments and determine which properties warrant closer inspection.

The workflow classifies results using a color-coded rating system in which green indicates a strong match between the detected footprint and the sketch on file, yellow suggests potential discrepancies that may require review, and red highlights significant differences that warrant closer inspection. Assessment staff apply the workflow to parcels selected for review during the county’s reassessment cycle, allowing appraisers to quickly evaluate targeted properties scheduled for assessment.

The county then publishes the results through ArcGIS Online as GIS data layers that assessment staff can access through a web application built with ArcGIS Maps SDK for JavaScript.

Bringing parcel records, aerial imagery, building sketches, and AI-generated footprints together in a single map provides appraisers the geographic context they need to quickly evaluate potential discrepancies.

Assessors use these scores alongside imagery and parcel information to determine which properties require additional review and which ones can move through the reassessment process more quickly.

Utah County eliminated 86 percent of reviewed parcels from further investigation, significantly reducing the number of properties requiring follow-up assessment.

The county applied this geospatial AI workflow to 56,993 properties approaching their reassessment deadline. The analysis identified 48,846 properties with strong matches between aerial imagery and assessment records, while 7,494 warranted additional review and 653 emerged as high-priority candidates for field inspection.

“The assessor doesn’t have to worry so much about going out and finding and discovering where the issues are,” said Wawro. “They can actually focus on deciding what to do and how to assess.”

With far fewer properties requiring follow-up, appraisers can spend less time identifying properties that need attention and more time making assessment decisions. The county can prioritize inspections, use staff resources more efficiently, and scale operations without adding workload.

For Utah County, the value of geospatial AI extends beyond improving property assessments. Geospatial AI acts as an additional layer of validation alongside permits, field inspections, and appraisal expertise, helping staff analyze imagery more efficiently, identify potential discrepancies at scale, and focus their expertise where it has the greatest impact.

By combining AI with its operational GIS environment, the county has demonstrated how government agencies can modernize long-standing workflows, scale their operations, and make better use of staff expertise and time without overhauling established business processes.

Building on its success with property assessments, Utah County has begun applying similar geospatial AI workflows to other county initiatives, including storm drain detection and mosquito abatement efforts. These projects demonstrate how aerial imagery, GIS, and AI can work together to help staff identify patterns, prioritize resources, and improve operational awareness across departments.

As geospatial AI capabilities continue to evolve, Utah County expects to expand on these capabilities, identifying new opportunities to automate analysis and support decision-making. The county’s approach provides a model that other local governments can adapt to unlock new value from the geographic data they already maintain.