Fall 2017

Maricopa County Quickly Builds Customized Parcel Viewer

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Parcel Viewer allows users to annotate parcels with additional information by drawing on and adding text to parcels.

The Maricopa County Assessor’s Office modernized its parcel visualization app using the developer edition of Web AppBuilder for ArcGIS. GIS Programmer analyst Kacie Baker built the app then extended its capabilities using the ArcGIS API for JavaScript.

It is now easier than ever for parcel assessors, real estate agents, appraisers, and other interested parties to review national boundaries, jurisdiction, zoning, and ad valorem valuation in Arizona’s Maricopa County.

“Our Parcel Viewer application helps staff and the public identify, classify, and value real property parcels within Maricopa County, Arizona,” Baker said. “The application serves up several years of aerial photography, zoning, and flood layers, along with links to third-party services.”

Within a two-month timeframe, Baker and her team built the web app they needed. She broke down the app’s search capability by categories, then added aerial photographs and basemaps to show zoning, flood lines, and other options for each parcel. The app also allows users to annotate parcels with additional information by drawing on and adding text to parcels. Baker added a “My Location Finder” so users, such as assessors in the field, can click a GPS icon and zoom to their location.

“Web AppBuilder did a lot of the start-up work for us,” Baker said. “It gave me a structure and saved a whole bunch of time as it is streamlined and easy to use. It allows me to customize as I need. I had to incorporate the Assessor’s Office standards for color scheme and certain images, so I had to customize.”

Change from the old public-facing maps was a bit difficult at first, Baker explained, but as people learned to use the new site, they appreciated its advanced functionality. For example, a buffer tool shows how many residential or commercial parcels are within a certain area. Users can export addresses for all those parcels—a tool that’s especially useful to owners and their representatives who are working with city permitting.

“We’re getting a positive response,” Baker said. “People regularly email us to say that the site is clean and easy to use. We continue to collect feedback to make the app even more valuable in the future.”