As we look towards a release of Esri’s ArcGIS Pipeline Referencing (APR) extension to manage our pipeline centerline representations and associated point/linear events, a lot of discussion has been centered around the functionality, front-end user interface and ease of use. But how can you get your data ready and structured to use these new tools?
Even though presentations at PUG or this year’s UC centered around the front end of these extensions, Esri has also done a ton of work to provide tools that assist in the creation, configuration and migration of data into APR compatible formats.
The vast majority of data stored in the pipeline space has historically been within an APDM or PODS (Relational or Spatial) schema.
Moving forward, the Utility Pipeline Data Model (UPDM) is currently the best template to start with, but we should also see an upcoming release of a PODS Next Gen model that will be APR compliant.
That said, it’s not a requirement from Esri to use either of these database schemas (UPDM or PODS Next Gen) for the APR tools, but it will be much less up-front configuration if you do!
If you need further clarification on the current and future database models, check out a previous post on the different options.
For this post, we are going to take a bit of a deeper technical dive and look at the core features for APR and how to use some of the upcoming APR tools to get existing data into this format.
The core for APR and the new LRS networks are a bit different than we are all used to in PODS or APDM database schemas used in the past. As you look to transition to the new tools and LRS network configurations, there are four main components to storing and managing the linearly referenced pipeline representations.
These are Centerline (Polyline Feature Class), Centerline Sequence (Table), LRS Networks (Continuous and/or Station Series – Polyline MZ) and Calibration Points (Point Feature Class). So what exactly are each of these components?
The centerline feature class is a polyline that simply represents the geometry of the transmission pipeline system. One centerline spatial representation can participate in multiple routes or LRS networks, but inherently, this stores where the pipeline exists in the world.
Next is the CenterlineSequence table. This table is a cross-reference table that organizes and determines the centerlines that may participate in one logical route. Again, many centerlines can participate in one route.
The APR tools inherently use the centerline sequence to understand the pipeline route representations. Think of this as the table and relationship used to roll up one or more centerlines into their logical routes.
The logical routes then participate in either a Continuous or StationSeries LRS network, or both! If possible, it would be good to manage only one LRS network so users would not need to translate measures between the two, but the tools and applications definitely support maintaining both. An example of this would be operators that do not support equation points, simply go with a continuous network.
As the screen shots show below, there is a key difference between the Continuous and StationSeries LRS networks. The continuous network below has a one to one relationship between the Route and its representation as a PolylineMZ in the Continuous Network. One route = one linearly referenced pipeline.
The Station Series Network, shown below, adds another level in the hierarchy and allows the configuration of a LineID, LineName and LineOrder. Think of these as how Station Series features have been organized into a logical LineLoop for APDM or PODS Spatial.
In the new APR core, one Route = one linearly referenced centerline in the StationSeries network, but multiple station series features can be rolled up into a Line. In this scenario, a Line ID, Name and Order would need to be applied in order for the APR to appropriately manage the StationSeries Network.
The Order is an important component of the Station Series network since this defines the order of the individual series that make up a Line.
Lastly, The CalibrationPoint feature class is a point feature that stores the measure values for the particular route. At a minimum we will have calibration points at the beginning and end of the route (starting at 0 and ending at the end measure), but ideally your organization has calibration points all along the pipeline centerline that can be loaded and used for more accurately calibrated pipelines.
Calibration points can exist at any known spatial location with a known measure value. Examples include, PIs or Pipe Bends, known crossings, valves, taps, tees, elbows, etc. Anywhere we have historical references to the stationing and also know where that location exists spatially, a calibration point can be added.
The diagram below shows the complete picture and the primary and foreign keys between each of these components of the core APR configuration. As you can see, the Centerline feature is the foundational spatial component and is tied to the centerline sequence table by the CenterlineID.
The CenterlineSequence table then rolls all centerlines up into one RouteID. This can be one Centerline per Route or multiple Centerlines per Route, with a numerical sequence.
The RouteID is now the foreign key for the LRS networks. As described above, if we are using the Station Series network, multiple series can be rolled up into a logical Line representation. Finally, the RouteID from the LRS network is tied to the CalibrationPoint feature class in order to have known measure values along the route and tie the calibration points/measure to its correct pipeline.
Are we clear??!? Crystal…
It definitely can be a bit complicated, but hopefully that helps to get you thinking towards how your current pipeline representations will be stored moving forward in the APR core (UPDM or otherwise).
So now that we have an overview of the core, how do we get our existing pipeline representations into this format? If you are looking to move to UPDM, there are a number of new, easy to use tools coming from Esri within the APR extension.
These new tools are available in both a Location Referencing Tools Toolbox and also in new right click functionality from the ArcGIS Desktop. The first is the ability to create a fresh UPDM GDB in order to load the centerline and calibration point features.
This would be a great start for an organization to run through a pilot and see how you can best manage your pipeline representations moving forward.
This process is as simple as clicking the ‘Create UPDM Geodatabase’ tool in the toolbox, defining the output location, applying a spatial reference/coordinate system, any tolerances, unit of measure and event measure storage. Once this is all set, click OK and the tool does the rest.
You now have a fresh UPDM database GDB in place. This schema, shown below, includes all UPDM feature datasets, feature classes, tables, LRS Networks and LRS events.
It’s ready for data to be loaded! Let’s think back to a PODS Relational implementation and what that would have taken to stand up a fresh schema. At least a half day of DBA time, at best, and dependent upon availability. This functionality is now in our hands!
The next step would be to load the pipeline centerline features and corresponding calibration points. As you can see from the screenshot below, there is a nice wizard to do accomplish this task that is initiated from the right click menu on the LRS network.
This dialogue walks you through selecting the polyline feature class, defining the routeID, and a from and to date field. Route attribute mapping is also supported and we can define the route names, line name and eventID.
Subsequently, the wizard walks the user into a tool to update the calibration points. If you are using PODS Spatial or APDM, this is a direct import and setting a series of variables before the tool will update the M values of your LRS Network (PolylineMZ).
What’s next?? Event Management, Event Response Types and Event Loading…but that seems best served for a subsequent post. As always, let SSP know if you need help with this process or if your organization is best served with a pilot project once the APR tools are out.
We are lucky enough to get our hands on it first, but we are excited about what these tools hold for the entire Pipeline GIS space moving forward.