Cartographic realignment

Cartographic realignment makes corrections to the geometry of the route where no change has occurred in the physical world. This activity should be considered as a data correction routine rather than a data edit. As a result of this activity, the route may increase or decrease in length without changing the calibration of the route. There is no impact on events as a result of this edit. The daily workflow of updating the highway geometry based on new aerial imagery, as-built drawings, or input from field data collectors can be achieved using this tool.

Esri Roads and Highways puts the burden on the linear referencing system (LRS) editor to identify the correct geometry for any given highway change. Since source geometry may come from sources outside of the GIS, Roads and Highways allows you to select source geometry from ArcGIS feature classes, shapefiles, or computer-aided design and drafting (CADD) files.

Behind the scenes, Roads and Highways applies edits to the geometry to centerlines and the centerline sequence table (see Data in the ALRS for more information about the data elements in Roads and Highways) to reconstruct the new shape and preserve the calibration of the route as it existed before the cartographic realignment was applied.

Roads and Highways uses redlines and source geometry to perform realignments. While the use of a redline is optional, the use of source geometry is required.

Note:

You should never directly edit the centerline feature class, as this may corrupt your LRS networks.

Steps:

1. Start ArcMap.
2. Set up the editing environment to use Roads and Highways.
3. Use the ArcMap navigation tools to zoom to the location of the alignment change.
4. Click the Networks menu on the Roads And Highways Editing toolbar.
5. Choose the LRS Network layer you want to edit.
6. Click the Activity Type menu and choose Cartographic Realign Route.
7. Optionally, use the Select Redline Features tool to choose the redline for the new route.

   Choosing a redline feature is optional. You can skip this step; however, you will need to manually enter the route and measure information on the Cartographic Realign Route dialog box.

8. Use the Select Source Geometry tool to select the source geometry for the new alignment.
   Note:

   If the redline and source geometry are close together, you can turn off the redline in the ArcMap table of contents before selecting the source geometry. This can prevent the selection of unwanted redline features in the source geometry selection.

9. Optionally, if you did not select a redline, or the redline was missing attributes, the parameters on the Cartographic Realign Route dialog box need to be manually entered.
   1. Enter an effective date for the cartographic realignment.
      • In the Effective Date field, manually enter a date. Acceptable date formats include M/D/YY, MM/DD/YY, or MM/DD/YYYY.
      • Click the calendar menu and select the alignment date from the calendar.
      • Enter a Route ID or click the Select Route tool to make a selection from the map. As soon as the route ID is entered, the tool investigates the spatial relationship between the source geometry and the route and identifies the From and To measure values to autopopulate.
   2. Enter the split From measure.
      • Manually enter a From measure.
      • Click the Select From Measure tool and click the map at the location of the From measure.
   3. Enter the split To Measure.
      • Manually enter a To measure.
      • Click the Select To Measure tool and click the map at the location of the To measure.
   4. Choose the appropriate option in the Existing Calibration Points area.
      • Retire—The calibration points within the edit section are retired with the To Date set equal to the effective date of the edit.
      • Transfer Proportionally—The calibration points within the edit section that existed before the edits are transferred to the new geometry such that the spacing between the calibration points is maintained proportionally before and after the edit.
10. Click OK.

    The Cartographic Realign Route dialog box appears. Values on this dialog box are autopopulated from the selected redline.

11. Verify the following parameters of the new alignment are correct:
    • Effective Date
    • Route ID
    • From Measure
    • To Measure
12. Click OK.
    Note:

    Sometimes cartographic realignments are performed against routes that overlap with other routes. Cartographic realignment of one highway does not impact the geometry of the overlapping highway.