GIS Based Tools for County Road Management Right-of-Way Land Value Analysis. January 12, 2012

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1 GIS Based Tools for County Road Management Right-of-Way Land Value Analysis January 12, 2012

2 Reasons for Needing Accurate Land Values Asset Management 1999 GASB Statement 34 Corridor Studies Scoping Studies Previously, the County was subdivided into 20+ zones with average land use costs assigned to each zone. The old process was very subjective, time consuming to update, and difficult to audit. MCDOT initiated a study to develop better a way to accurately and consistently estimate land values.

3 Asset Management New land assets dedicated to the County each year must be assigned a dollar value per GASB 34. The methodology must be consistent from year to year, use a reliable data source, be easily updatable, and be auditable by the State. In FY 2011 MCDOT received acres of land dedications worth $34,239,000. MCDOT s FY 2011 transportation assets exceed one billion dollars.

4 Corridor Studies Calculate land values simultaneously for multiple corridor alignments and ROW widths. Calculate these values is a timely, accurate, cost effective, and consistent manner. Save time and money. Identify property owners and addresses for future notification.

5 Scoping Studies Calculate values for multiple roadway segment alternative alignments and ROW widths. Calculate these values is a timely, accurate, cost effective, and consistent manner. Save time and money. Identify parcel owners and addresses for future notification.

6 Jacobs developed a set of user friendly GIS based tools that allows MCDOT staff to: Develop a 3D layer of Maricopa County that estimates land values for roadway ROW based on the Maricopa County Assessor Data Estimate land values for new roadway ROW based on the 3D Land Values layer Extract parcel information and parcel land values along a specific corridor

7 Land Valuation Analysis Process Review

8 Land Valuation Process 1 ROW area represented by white spaces is not valuated by assessor Study area: Entire County (Private Lands Only) Primary Database: Maricopa County Assessor Parcel Data Issues: ROW areas are not valuated by assessor (White Spaces shown in figure)

9 Land Valuation Process 2 Insert placeholder parcels to create continuous parcel layer Insert small placeholder parcels in ROW areas and associate them with nearest parcel land value to create a continuous parcel layer.

10 Land Valuation Process 3 Convert each parcel to sample data point with land value Convert each parcel to a center point to create a sample data point. Each sample data point has a land value per square foot.

11 Land Valuation Process 4 Subdivide entire area into a grid of pixels Subdivide the entire area into a grid of tiny pixels.

12 Land Valuation Process 5 Select sample points within 1000 ft radius to calculate average land rate For each pixel, select sample data points within 1000 ft radius to calculate LAND VALUE PER SQUARE FOOT

13 Land Valuation Process 6 Generate 3D surface Use each pixel to create a 3D surface layer. Z value of pixel represents land value. Color spectrum from brown to blue, represents increasing land values

14 Land Valuation Process 7 Drape new roads on 3D surface to extract land values Drape new roads on 3D surface to extract land values

15 GIS BASED AUTOMATED TOOLS Assessor Data Update Tool Land Values Calculator Tool Corridor Analysis Tool

16 Assessor Data Update Tool: Updates the Land Value 3D Surface Layer, which is utilized to estimate land values throughout the County. 5 step process Administrative task Processing time depends on the computer configuration. It takes about 1.5 days with a fairly high end computer. Only needs to be updated once a year. Requires the latest county assessor parcel data.

17 3D Land Valuation Surface Layer

18 Land Values Calculator Tool: Estimates land values for roadway ROW. Overlays the roadway ROW GIS file on the Land Value 3D Surface Layer to extract land values for each road. Requires a basic GIS line file with the roadways for which Land Values need to be estimated. The GIS line file should also include a column that has the ROW width value. Output includes a GIS shape file with land values for each roadway segment.

19 The tool automatically adds the following fields: New Column Name ShLength ShWidth ShArea LandValue LandRate Private_Value Public_Value Private_Length Public_ Length Description Length of ROW Width of ROW Area of ROW in Sq. Ft Calculated Value of ROW Land Rate ($/sq. ft) Calculated Value of ROW within Private Land Calculated Value of ROW within Public Land Calculated Length of ROW within Private Land Calculated Length of ROW within Public Land DEMONSTRATION

20 Corridor Analysis Tool: The corridor analysis tool allows MCDOT staff to extract parcel information and parcel land values located within a specific corridor s ROW based on a user specified search radius. Outputs include a list of affected parcels with Parcel location Ownership Land and structure values Average land rate Percentage of parcel within the corridor ROW

21 Corridor Analysis Toolset DEMONSTRATION APN Parcel ID ADDRESS Parcel Address AREA Parcel Sq. Ft. OwnerName Owner Name OwnerAdd1 Owner Address OwnerAdd2 Owner Address City Owner City State Owner State Zipcode Owner Zipcode Country Owner County SiteAddres Site Address Suite Site Suite CitySA Site City ZipcodeSA Site Zipcode ProptyType Property Type (Commerical, Vacant, Etc) LandFCV Land Value ImpmntsFCV Improvement Value TotalFCV Total Value ProptyUseC Proprty Use Code Block Block Tract Track LndLegalCl Land Legal Code ImprLegalC Improvement Legal Code TOTSQFTLan Total Sq. Ft. of Land Number_of_ Number of Units OrigPclAre Parcel Sq. Ft. RateSqftLV Land Value per Sq. Rate LVtoTotV Land Value to Total Parcel Value

22 Who Would Benefit from these Tools ROW Department Estimate preliminary ROW land values of existing roadways for asset management purposes. Planners and Design Engineers Alternative Analysis of New Roadway Corridors: Estimate preliminary ROW costs for each roadway alternative. Roadway Widening: Identify the impacted parcels and the percent of impact to each parcel. Public Involvement Staff Identify and extract parcels affected by a roadway corridor includes site and owner address information for public outreach.

23 Savings to MCDOT Based on currently ongoing and previously completed studies, an agency spends about: ~ 8 hours for coordination to request assessor data from County Assessor and other pertinent data. ~ 8 hours for QA/QC (does not include time for requesting data again if incorrect). ~ 400 hours to obtain affected parcel numbers, owner and site addresses, land value and structure value, percentage of impact to each parcel, analysis, reporting, and mapping for each corridor or corridor alternative.

24 Savings to MCDOT This Application would require: ~ 1.5 day (automated processing time) to replace the assessor database in the application (ONE TIME PROCESS). ~ 1 hour to generate/compile background GIS data. ~ 15 minutes to generate affected parcel numbers, owner and site addresses, land value and structure value, percentage of impact to each parcel for one corridor or all corridor alternatives.

25 Asset Management Savings Public Works Real Estate Division Analysis Estimated 23 hours of staff time to assign the ROW values for 23 subdivisions dedicated to MCDOT in FY This application would only require about 4 hours of staff time to estimate the ROW values for these 23 subdivisions.

26 Questions?