Parcel corner location update

This topic applies to ArcGIS for Desktop Standard and ArcGIS for Desktop Advanced only.

Complexity: Beginner Data Requirement: Local Government Sample Data Data Path: \TaxParcelEditingMap\MapsandGeodatabase\ Goal: Learn how to update the locations of parcel boundaries and corner points using the Local Government Information model for ArcGIS.

When the parcel fabric is enabled with the Local Government Information Model, efficient workflows can be used to perform common parcel editing tasks such as a parcel merge and a parcel split. This workflow describes the steps for making ad hoc updates to the locations of parcel boundaries and corner points.

The workflow uses the sample dataset that is downloaded with the Tax Parcel Editing map on the resource center.

Learn how to migrate parcel data to the parcel fabric schema in the Local Government Information Model.

Ad hoc updates of the locations of parcel boundaries and points are done when there is a need to change the spatial positions of parcels because of misalignments with other data. Parcel boundaries that have been digitized or imported from inaccurate CAD files often need to be updated to align with more accurate data such as high-resolution imagery.

When parcels in the parcel fabric have correct dimensions, that is, COGO dimensions that match the record of survey, a fabric least-squares adjustment can be used together with control points to adjust and derive highly accurate locations of parcel corner points.

However, when dimensions are unreliable, you can, in the interim, make ad hoc positional updates to parcel boundaries and corner points instead of reentering dimensions and running a least-squares adjustment.

The workflow consists of the components shown in the diagram below:

Search for parcels

Steps:

1. Open the TaxParcelEditingMap document located in the MapsandGeodatabase folder.
2. On the Table Of Contents window, make the layers that contain the parcels you want to update selectable. For example, if you want to update the boundaries and points of lot parcels, tax parcels, and encumbrance parcels, you would make the Lots and Units, Tax Parcels, and Encumbrances layer selectable.

   In the sample dataset, make both the Tax Parcels layer and the Lots and Units layer selectable.

For the workflow using the sample data, the visibility of the Historic Parcels layer has been turned off.

3. Search for the parcels you want to update. In the sample dataset in the TaxParcelEditingMap document, search for parcel 1921201004.

Select parcels

You will be updating the boundary locations of parcel 19-21-201-004 and its adjacent parcels:

Steps:

1. Start an edit session and use the Select Parcel Features tool located on the Parcel Editing toolbar to select parcel 19-21-201-004 and surrounding parcels as shown in the graphic below.

   You may need to zoom out for parcels to be visible.

Move parcel boundaries and points

In the workflow, the boundaries and corner points of the selected parcels will be updated and aligned with high-resolution imagery. Currently, the boundary lines are misaligned with the high-resolution imagery as shown in the graphic below. For visual simplicity, the visibility of Lots and Units layer has been turned off.

Tip:

You can download the Local Government Imagery Hybrid Basemap for the Local Government sample dataset from the land records resource center.

Steps:

1. Click the Transform Parcels tool on the Parcel Editor toolbar to display the Transform Parcels toolbar.
2. Use the Move Parcels, Scale Parcels, Rotate Parcels, and Scale/Rotate Parcels tools on the Transform Parcels toolbar to align parcel boundaries with the underlying imagery.
   If you are using the sample dataset and don't have the sample dataset imagery added to the map, you can estimate how much to move, scale, and rotate the selected parcels.

3. Click Commit Transformation on the Transform Parcels to save the parcel transformation.

   Choose whether to create new center points or keep original center points for curved boundaries. For the workflow, click Yes on the Save Transformation dialog box.

4. If necessary, use the Move parcel point tool to move individual parcel points.

5. Click Commit Transformation to save changes to parcel point locations.
All parcels sharing the points that were moved will be updated. This includes underlying lot parcels, encumbrance parcels, historic parcels, and so on.


Note:

When changing the geometry of parcels, COGO dimensions on lines may no longer match the line shape geometry. For example, when moving a point, the bearing and distance of the line shape will change, but the COGO dimension attribute will not be updated. In the parcel traverse grid, bearings that differ by more than 10 degrees from the line shape and distances that differ by more than 20 percent of the line shape are highlighted in yellow.



You can maintain spatially accurate parcel corner positions with correct COGO dimensions using control points and the parcel fabric least-squares adjustment. Parcels with inaccurate or unreliable dimensions should be reentered with the correct COGO dimensions from the survey record. A least-squares adjustment can be run on a selection of parcels to adjust them to specified control points.

Learn more about the parcel fabric least-squares adjustment

Annotate parcels

Annotation does not need to be updated for positional updates to parcels. If the annotation is feature linked, it will move to the new location of the updated boundaries. If necessary, use the Edit Annotation tool to edit and change the placement of the generated annotation.

To re-create annotation for selected parcels, click the Annotate Parcel Courses tool on the Parcel Editor toolbar.

Attribute parcels

Since new parcels were not created in the workflow, entering new attribute information is not necessary. You can edit existing attributes by selecting the parcels and opening the Attributes window. You can also edit parcel attributes on the Parcel Details dialog box under the Properties tab.