Pima County Geographic Information Systems

Finding Parcel Areas

Overview

Unfortunately, no agency, department or organization has the legal responsibility to track and report parcel areas. Furthermore, no measurements are exact. We can only do the best we can with available information of record or have a surveyor make a determination based on all the facts and circumstances.

If a parcel is in a subdivision, that parcel's subdivision plat map defines the parcel's boundaries at the time of platting and is often the best source for finding parcel area short of survey. See Parcel areas from subdivision plat maps below. Some subdivision plat maps clearly specify parcel areas and some don't. Those that don't show areas show only lot dimensions and angles. When parcel area isn't specified on a plat map, a surveyor (among others) could calculate the parcel's area from the dimension information on the subdivision plat map.

It's possible that one or more surveys may have been done in your area of interest. See Parcel areas from records of survey below.

The estimated parcel area on our website's parcel detail pages is calculated from our interpretation of the parcel's boundaries as displayed on our maps. Therefore, the area value is subject to errors inherent in any mapping process. See Estimated parcel areas from GIS data below. If you click on "Assessor Parcel Detail" on our parcel detail page the Assessor shows "Land Measure" with the Assessor's estimate of the parcel's area for assessing taxes.

For parcels that are not in subdivisions, then the parcel area may be estimated by the parcel's legal description on the deeds. Sometimes the legal description includes the area and sometimes it doesn't.

The method for determining parcel areas depends on just how accurate you need it. If the subdivision plat map, legal descriptions, existing surveys, and online map estimates are not good enough for your needs, then you should hire a surveyor. Even surveyors can disagree. Ultimately, if there was a parcel area or boundary dispute it would be resolved in the courts.

Since we can never know exact parcel areas, we suggest quoting the source along with the area such as:

• x.xx acres as taken from the Subdivision Plat Map.
• x.xx acres as calculated by ..... from subdivision plat map parcel dimensions.
• x.xx acres as estimated on the Pima County GIS web site.
• x.xx acres as estimated on the Pima County Assessor's web site.
• x.xx acres as taken from the deed recorded at (docket/page or sequence number).

• If the parcel of interest is in a subdivision, many Subdivision Plat Maps show parcel areas. You can click on the "Subdivision Plat Map" link on a parcel detail page (described above) to see the plat map. Or, you can turn on the "Subdivisions" layer on the Main MapGuide Map, and turn off the Parcels layer. Then double click on the subdivision to get to the subdivision plat map. (You have to turn off the parcels because they are on top of the subdivision layer, even though you can see the subdivision layer through the transparent parcel layer.)

  Read about TIFF Viewers for help viewing the scanned Subdivision Plat Maps.

• The parcel detail page for each parcel has "Parcel area" at the very bottom of the page. You can get to a parcel detail page by drilling down through Parcel Information Search or by double-clicking on a parcel on one of our MapGuide maps.

• A somewhat more complex way to find parcel area is to select one or more parcels on a MapGuide map and get a report. These reports show the area for each selected parcel as well as the total area of all selected parcels.

  To select one parcel, simply click on the parcel. You can then use SHIFT-click to add more selected parcels. To remove a selected parcel, press SHIFT and click on the parcel. See Selecting Map Features in the MapGuide Viewer Help for more but be sure to scroll down on the page to see the most commonly used methods.

  After selecting parcels on a MapGuide map, use one of these methods to get selected parcel area(s):

  1. Use the "Map Tools & Map Info." (Windows Internet Explorer users only) drop down at the top of MapGuide map and choose the "Calculate Area" tool to get the area report.

  2. Use the "View Report" tool on the MapGuide map tool bar and then select "Parcel Area and Values Report". You can also get to the "Parcel Area and Values Report" by right-clicking in the map area, choose "Reports" and then "Parcel Area and Values Report".

• Many completed surveys are recorded as "Records of Survey". If a survey was done in your area of interest, you may be able to find the document using the "Records of Survey" link on the City of Tucson DOT Maps and Records web site or from the Pima County Recorder's "Survey Map" recorded documents. If a parcel is in a typical residential subdivison, then it's not likely there will be a record of survey beyond the subdivision plat map itself unless a special survey was done for some specific reason.

See the Tips and Help link at the top of MapGuide maps for more help.