Create the LRS, networks, events, and intersections

Available with Location Referencing license.

The following information describes the process of linear referenced data modeling, loading, and route editing using the ArcGIS Roads and Highways extension.

LRS dataset

A linear referencing system (LRS) dataset is a controller dataset in a feature dataset in the geodatabase along with all the feature classes that participate in the LRS.

Note:

You can view the LRS hierarchy from either the Contents pane or the Catalog pane.

Note:

The LRS dataset is visible only in ArcGIS Pro. An error message appears if a geodatabase that contains the LRS dataset is opened in ArcMap.

The following tools create an LRS dataset:

• Create LRS—The newly created centerline, calibration point, and redline feature classes are placed in a feature dataset with the same name as the provided LRS name.
• Create LRS From Existing Dataset—The existing centerline, calibration point, and redline feature classes that are not yet registered with an LRS must be in a common feature dataset. The feature dataset name can be different from the LRS name.

All tools in the Location Referencing toolbox require an LRS dataset to run.

Note:

Use the Migrate Object ID to 64 Bit tool to migrate the LRS dataset to 64-bit Object IDs.

Upgrading a dataset to 64-bit Object IDs is useful when Object ID values exceed 2.1 billion or if data is coming from cloud data warehouses.

Learn more about migrating to a 64-bit Object ID

You can review some of the information contained in the LRS dataset using the arcpy.Describe function. To review the LRS metadata and event behavior rules for a geodatabase with an LRS dataset, use the following functions:

FileGDB:

desc = arcpy.Describe("C:\\Data\\LRData\\LrsSchema.gdb\\Lrs\\Lrs")

lrsXML = desc.lrsMetadata

eventBehaviors = desc.eventBehaviorRules

EnterpriseGDB:

desc = arcpy.Describe("C:\\Data\\LRData\\LrsSchema.sde\\GPRefresh.DBO.LRS\\GPRefresh.DBO.LRS")

lrsXML = desc.lrsMetadata

eventBehaviors = desc.eventBehaviorRules

Writing to a file:

txtFile = open("C:\\Data\\LRData\\lrsXML.xml", "w")

txtFile.write(lrsXML)

txtFile.close()

Data modeling

Transportation professionals are routinely tasked with considering alternative routing options to ensure regulatory compliance, market, construction, and other business needs. This usually results in realigning (rerouting) a roadway. Realignment not only changes the pathways of roads but also impacts networks and events configured in a linear referencing system (LRS) data model.

To use Roads and Highways, your data must adhere to the LRS data model.

Learn more about tolerance and resolution settings for the LRS and the Events data model.

Configure an LRS

To create and configure an LRS, complete the following steps:

1. Create and modify an LRS.

   You can use either the Create LRS tool or the Create LRS From Existing Dataset tool to create an LRS.

   To modify an existing LRS, use the Modify LRS tool. This includes enabling conflict prevention in the LRS.

   Learn more about creating and modifying an LRS

   Note:

   If you have existing point features that can be used as calibration points, use the Append tool to append the point features to the calibration point feature class before loading routes into the LRS Network (step 5 below).

2. Create an LRS network using one of the following tools:
   • Create LRS Network
   • Create LRS Network From Existing Dataset

   To modify an existing LRS Network, use the Modify LRS Network tool.

   Learn more about creating and modifying an LRS Network

3. Create LRS events using one of the following tools:
   • Create LRS Event
   • Create LRS From Existing Dataset

   To add referent fields to the event feature class, use the Enable Referent Fields tool. This tool enables the referent fields by allowing you to register existing fields as referent fields.

   To modify an existing LRS event, use the Modify LRS Event tool.

   Learn more about creating and modifying LRS events

4. Create LRS intersections using one of the following tools:
   • Create LRS Intersection
   • Create LRS Intersection From Existing Dataset

   To add intersections to the intersection feature class, use the Generate Intersections tool.

   To modify an existing LRS intersection feature class, use the Modify LRS Intersection tool.

   Learn more about creating and modifying LRS intersections

5. Load routes into the LRS Network using the Append Routes tool.

   Route shapes can be regenerated using the Generate Routes tool.

   Learn more about loading routes into an existing LRS Network

   Learn more about setting gap calibration rules for an LRS Network

6. Create calibration points using the Generate Calibration Points tool.

   Note:

   If you have existing point features that can be used as calibration points, use the Append tool to append the point features to the calibration point feature class before loading routes into the LRS Network (step 5 above).

7. Prepare centerlines.

   To remove overlaps that may cause data errors, use the Remove Overlapping Centerlines tool.

8. Load event data using the Append Events tool.

   Learn more about creating and modifying LRS events

Realign and reroute data

Use the following tools to realign (reroute) and maintain linear referenced data:

• Create Centerline—Determine whether one or more centerlines exist for the realignment portion of a route or routes.
• Event Behavior—Consider how event behavior rules will apply to your route edits.
• Apply Event Behaviors—Apply event behaviors to keep event measures in alignment with route edits.
• LRS Network—Determine whether other LRS networks are affected by route edits.
• Generate Routes—Regenerate shapes for LRS networks.

Route editing workflows

Similar workflows can be created for other route editing activities such as create, extend, realign, reassign, retire, calibrate, and cartographic realignment.

The following table lists the steps required to edit and maintain roadway data:

Route edit activity table

Step	Workflow	Create	Calibrate	Cartographic Realignment	Extend	Realign	Reassign	Retire
1	Create a centerline.	Yes	No	No	Yes	No	No	No
2	Perform the editing activity.	Yes	N/A	N/A	Yes	Yes	Yes	Yes
3	Run the Apply Event Behaviors tool.	No	Yes	Yes	Yes	Yes	Yes	Yes

If additional LRS networks are configured, repeat the edit activity for each affected network.