Cartographic realignment

Updating the route geometry based on aerial imagery, as-built drawings, or input from field data collectors in a manner that does not change measures can be achieved by direct modifications to the centerline. This is known as cartographic realignment. ArcGIS Roads and Highways allows you to change the shape of centerlines and preserve the calibration of the underlying routes as they existed before the cartographic realignment was applied. The results are achieved by editing the geometry of the centerlines that are associated to the route.

Note:

You need the centerline feature class visible in the table of contents to do cartographic realignment.

1. Start ArcMap.
2. Set up the Roads and Highways editing environment.
3. Use the ArcMap navigation tools to zoom to the location of the alignment change.

   

4. Uncheck the network layer in the table of contents.
5. Check the centerline layer in the table of contents.
6. Click the Edit tool on the Editor toolbar and click the feature.
7. Double-click the centerline's edge.

   The selected centerline's vertices appear.

   

8. Edit the vertices of the selected centerline to match the correct alignment of the route.

   You can do this by adding and deleting the vertices and by modifying segments. You can also use the geometry editing tools available in ArcGIS Desktop.

   Note:

   If your centerline is reshaped as a curve, Roads and Highways will convert the curve into a densified polyline feature. To set the level of densification of curves to polylines, click the Advanced LRS Editing Options button on the Roads And Highways Editing toolbar.

   

   Note:

   • If a message appears that is related to acquiring locks or the need to reconcile, Roads and Highways conflict prevention is enabled in Roads and Highways Desktop.

   • If a centerline is shared by concurrent routes in the same network, routes from a different time span, or routes from a different network, all those routes need to be locked to perform the cartographic realignment.
9. After editing the vertices to match the proposed alignment of the route, right-click anywhere on the map and click Finish Sketch.

   

   Note:

   If an elevation model is configured with the LRS, the z-values on the centerline being edited will be updated using the elevation model. To configure an elevation model with the LRS, see step 14 in Creating a new LRS.

10. Check the network layer in the table of contents.

    The route is now cartographically realigned.

    

    Note:

    • After centerlines are updated, the route shapes in all networks are also updated. However, the event shapes for internal events and locations of the Roads and Highways managed intersections are not updated until you click the Apply Updates button on the Roads And Highways Editing toolbar or save your edits. For more information, see Event behaviors.
    • The intersections will be updated only when any referent offset events are present in the LRS. These referent offset events should have the Honor Referent Location event behavior set up for cartographic realignment.

      

    • In case you do not have any referent offset events in the LRS and want to update the intersections on the basis of the cartographic realignment, you can use the tools discussed in Updating an LRS intersection class and Update Intersection Points to do so.
    • When an event is the same length of the cartographically realigned section or only part of the section, the event will also be updated to match the route shape once you click the Apply Updates button on the Roads And Highways Editing toolbar.
    • It is also important to note that when the centerlines are edited, all routes in all networks, across all times, are modified accordingly.
    • If there exists a calibration point in the cartographic realignment section, you have an option to either delete or proportionally snap the affected calibration point to the new realignment.

      

    • If you don't want calibration points to be deleted or proportionally snapped, you can choose to have them ignored during a cartographic realignment so you can manually place them on the route where you want after the cartographic realignment. To enable this capability, check the option Do not update calibration points as part of cartographic realignment in the Advanced LRS Editing Options on the Roads And Highways Editing toolbar. This option is specific for each .mxd and can only be enabled if all the networks in your LRS do not have the Update route length and recalibrate the route based on change in geometry length option enabled.

When the route's geometry is cartographically realigned to increase or decrease in length, the resulting alignment will follow the geometrical length of the centerline if you have selected the option on the Roads And Highways Editing dialog box. To do so, right-click the LRS Network in the Catalog window and click Properties, and then click the Calibration tab.

In the image below, a cartographic realignment was performed on the route. The measure length of the route increased as a product of the realignment. Checking the Cartographic Realignment option selected on the dialog box will result in re-calibration of the route by updating the measure length. If the option is checked, the route will get recalibrated per the new length of the route after the cartographic realignment. If the option is unchecked, only the cartographic realignment will be applied, which means that the route will not be recalibrated and the measures will remain the same as they were before the cartographic realignment.