How To: Project shapefiles from the NAD27 to the NAD83 datum


This example shows how to use the ArcView Projection Utility to project shapefiles from the NAD27 to the NAD83 datum.

The instructions in this article assume that the input shapefile has no projection defined.

The ArcView Projection Utility will not project data stored in a location with any spaces in the path to the data.


Example projection parameters:

Projection Name: NAD_1983_California_III
Units: US Survey Feet
Projection: California State Plane
Geographic Coordinate System: NAD27
Zone: 3

Projection Name: NAD_1927_California_III
Units: US Survey Feet
Projection: California State Plane
Projection: NAD83
Zone: 3

  1. Start ArcView 3.x, and click on File > ArcView Projection Utility to start the Projection Utility.

    In the 'Step 1' dialog box:
    A. Browse to select the shapefile(s) to be projected. If the shapefile is displayed in the View, the shapefile is listed automatically.
    Step 1 Screenshot 16219

    B. Click Next on the 'Step 1' dialog box.
  2. In the 'Step 2' Dialog box:
    A. Select, under 'Coordinate System Type', the Projected radio button.
    B. Select, from the Name dropdown menu, NAD_1927_California_III[26743].
    Step 2 Screenshot 16219

    C. Click 'Next'. A dialog prompts to save the projection definition to a file. Click 'Yes'.
  3. In the 'Step 3' dialog box:
    A. Change the 'Coordinate System Type' radio button to 'Projected'.
    B. Select, from the 'Name' dropdown, NAD_1983_California_III[26943].
    C. Select, from the 'Units' dropdown, Foot_US[9003].
    Step 3_1 Screenshot 16219

    D. Check the 'Show Advanced Options' box, and select the 'Datum' tab.
    E, Select, from the Geographic Transformation: dropdown, NAD_1927_To_NAD_1983_NADCON.
    Step 3_2 Screenshot 16219

    F. Click 'Next'.
  4. At the 'Step 4' dialog box:
    A. Click 'Browse' to specify a name and location for the new output shapefile.
    B. Click 'Next'.
  5. The ArcView Projection Utility Summary displays the names of the input and output shapefiles, and the input and output projection information entered.

    Click 'Finish'.

    Optionally, add the new projected shapefile to the View. However, because ArcView 3.x does not project data on the fly, the input and output shapefiles do not line up in the View window.

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