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    • Pima County Coordinate System (PCCS)

    The Pima County Coordinate System (PCCS) was created to minimize linear distortion at the topographic surface throughout as much of the county as possible. The main objective was to design a system consisting of four zones with linear distortion not exceeding about ±20 parts per million (±0.1 ft. per mile or 1:50,000) in populated parts of Pima County. The areas in Green in the image below represent the ±20 parts per million within each of the four PCCS Zones.
    Pima County Coordinate System Zones (PCCS)
    A stakeholders meeting was held on October 26, 2016, to solicit input and support for the PCCS. Representatives from Geodetic Analysis, Pima County and City of Tucson survey departments, Pima County Public Works,  tribal agencies, members of the Arizona Professional Surveyors Association, and private sector surveying and engineering firms were present. They provided insight and overwhelming support for the development of the PCCS and Low Distortion Projections.

    The graphic above shows the Arizona State Plane Coordinate System 1983 Central Zone distortion image areas in dark blue beneath the PCCS zones areas in green.  That coordinate system's blue areas beneath the PCCS zones illustrate that most of Pima County far exceeds the desired ±20 parts per million, with a large percentage being ±100 ppm.

    Each of the PCCS zones were developed through the rigorous design of Low Distortion Projections (LDP). The LDP design process corresponding PCCS distortion images, and projection parameters are detailed in the PCCS Project Report below.  The report serves as a guide for defining and using the PCCS zones by mapping professionals.  Zone distortion maps and projection parameters are also available for viewing and download in the tabbed pages below.

    PCCS can be used directly by GIS and GPS software for the direct transfer of field data to and from information systems in surveying, engineering, infrastructure, and environmental disciplines.  Use of PCCS improves the spatial location of geographic features through minimized distortion and ease the transferability between geospatial systems.

    Note that PCCS is not being used as the primary coordinate system and projection parameters in the Pima County GIS Library. Pima County continues to use the Arizona State Plane Coordinate System NAD83 HPGN. PCCS is being used in selective conditions where higher spatial accuracies are desired, such as in parcel mapping, land surveying, and engineering.

    Pima County Coordinate System (PCCS) Report

    Download - PCCS Zone 1 Map

    Pima County Coordinate System (PCCS) Zone 1 East*

    Linear unit:     International foot (ift)
    Geometric reference system:     North American Datum of 1983 (NAD 83)
    Reference ellipsoid:     Geodetic Reference System of 1980 (GRS-80)
    PCCS Zone 1 AreaProjection:     Oblique Mercator (local grid origin)
    Latitude of local grid origin:     32° 15’ 00” N
    Longitude of local grid origin:      111° 24’ 00” W
    Northing at local grid origin:     800,000.000 ift
    Easting at local grid origin:     160,000.000 ift
    Skew axis scale at local origin:     1.000 110 (exact)
    Skew axis azimuth at local origin:     +45° 00’ 00”

    * Also known as a Hotine OM or rectified skew orthomorphic (RSO) projection. Local origin also referred to as “center.” Can also be defined using the “true” or “natural” origin.

    Download - PCCS Zone 2 Map

    Pima County Coordinate System (PCCS) Zone 2 Central

    Linear unit:     International foot (ift)
    Geometric reference system:     North American Datum of 1983 (NAD 83)
    Reference ellipsoid:      Geodetic Reference System of 1980 (GRS-80)
    PCCS Zone 2 AreaProjection:     Transverse Mercator
    Latitude of grid origin:     31° 15’ 00” N
    Longitude of central meridian:     112° 10’ 00” W
    Northing at grid origin:     1,000,000.000 ift
    Easting at central meridian:     1,800,000.000 ift
    Scale factor on central meridian:     1.000 090 (exact)
    Download - PCCS Zone 3 Map

    Pima County Coordinate System (PCCS) Zone 3 West

    Linear unit:     International foot (ift)
    Geometric reference system:     North American Datum of 1983 (NAD 83)
    Reference ellipsoid:      Geodetic Reference System of 1980 (GRS-80)
    PCCS Zone 3 AreaProjection:     Transverse Mercator
    Latitude of grid origin:     31° 30’ 00” N
    Longitude of central meridian:     113° 10’ 00” W
    Northing at grid origin:     0.000 ift
    Easting at central meridian:     600,000.000 ift
    Scale factor on central meridian:     1.000 055 (exact)
    Download - PCCS Zone 4 Map

    Pima County Coordinate System (PCCS) Zone 4 Mount Lemmon **


    Linear unit:     International foot (ift)
    Geometric reference system:     North American Datum of 1983 (NAD 83)
    PCCS Zone 4 AreaReference ellipsoid:      Geodetic Reference System of 1980 (GRS-80)
    Projection:     Lambert Conformal Conic (single parallel)
    Standard parallel and grid origin:     30° 30’ 00” N
    Longitude of central meridian:     110° 45’ 00” W
    Northing at grid origin:     -620,000.000 ift
    Easting at central meridian:     30,000.000 ift
    Scale factor on standard parallel:     0.999 800 (exact)

    ** An alternative two-parallel definition can be used for this zone if necessary.

    Pima County Coordinate System (PCCS) Control


    PCCS NGS Project Control Map

    Pima County Coordinate System (PCCS) Projection files

    For use with Global Positioning System (GPS) Equipment and Geographic Information Systems.

    Presentations from the Arizona Professional Land Surveyors Conference (APLS) May 2017.
    1. Pima County Coordinate System usage within Pima County for Parcel Fabric Develop.

      Download Presentation: mp4 | pdf

    2. Pima County Coordinate System Design Development and usage for Surveying and GIS Mapping.

      3. Download Presentation: mp4 | pdf

    We want your feedback and comments

    For issues related to this information please contact Jack Avis, PLS at (520) 724-6815 or e-mail address.

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