Geospatial Analysis at Jefferson County Property Valuation

Administration

Jay Mickle, Director of GIS & Internal Technology

Responsible for assessing all real property at fair market value

287,000 mapped parcels; over 311,000 total property records

Statutory responsibility to inspect all parcels at least once every 4 years

Real property assessments broken up by land and improvement value

About the PVA

PVA uses a 3rd party extension to ArcMap to edit & maintain Jefferson County’s parcel map

Cadastral Mapping Maintenance

Residential Comparison Neighborhoods

Residential Comparison Neighborhoods

Residential Comparison Neighborhoods

Residential Land Value Discrepancies

-Use interpolation methods to create a prediction surface for residential vacant parcels by using land-sale data.

-Extract values from the prediction surface to derive a value per square foot for each vacant parcel.

-To reduce error from any one interpolation method, three different interpolation methods will be used and averaged.

Proposed Solution

Smoothed Surface of All Study Parcels

-High Values in established up scale housing areas

-High values in “trendy” areas

-High values in areas with large new housing developments

-Low values in urban low income areas

-Low values in areas with large parcel sizes and large amounts of undeveloped land

Commercial Land Analysis - Goals

Predict commercial land value in the Central Business District (CBD) and along major transportation corridors using data based on sales of commercial vacant land in those areas.

To create a marketable booklet containing tables, maps, and charts of commercial vacant land sales and the corresponding predicted land values in the CBD and along major transportation corridors.

CBD Prediction Map

Commercial Corridor Analysis

Need to study effect of foreclosures on property values

Lower sales prices affect our entire reassessment plan

Vacant structure data also reviewed alongside foreclosures

Foreclosure Analysis