Demystifying Pipeline Data Models
If you’re reading this, you’re likely involved with managing GIS pipeline data. If you aren’t, I recommend checking out an informative, relevant (and quite possibly more interesting) read on enhancing your GIS with integrations or connecting business processes to your GIS. If you’re still with me, strap in.
Why do we talk about data models so much in the pipeline space? From my years interacting with operators, vendors, and regulators, I believe it comes down to a handful of reasons:
- The regulatory landscape;
- The need for thorough and accurate data;
- Meeting demands of complex implementation architectures;
- Maintaining interoperability; and
- Aligning with industry standards for linear referencing.
The pipeline data model landscape can be a difficult one to navigate. Operators work with significant amounts of data and there is no shortage of models to explore.
In my last post, I introduced ArcGIS Pipeline Referencing (APR). APR is at the core of an integrated offering from Esri that incorporates linear referenced GIS (LRS) into the ArcGIS® platform. APR focuses on the “core” of the LRS, with modeling of the data on the line (events) being stored in either a Pipeline Open Data Standard Next Generation (PODS) or a Utility and Pipeline Data Model (UPDM).
This is a slight deviation from previous approaches, which has introduced some confusion. PODS and UPDM provide database models to organize your pipeline data, while APR provides a set of tools to manage and interact with it inside your GIS. Hopefully the diagram below helps explain it a bit.
With the emergence of Integrated Spatial Analysis Techniques (ISAT), pipeline operators have had methods to store data about their systems and the surrounding environment since at least the early 1990s (some methods probably pre-date that). These methods have continued to develop through the work of the PODS organization and contributors to the ArcGIS Pipeline Data Model (APDM).
Each of these have offered unique benefits to the industry, but they’ve also introduced unneeded fragmentation to the landscape. As I mentioned in my previous post, APR helps simplify this by providing consolidation.
Pipeline Open Data Standard (PODS)
PODS is the data model standard for the pipeline industry. Founded in 1998, PODS was developed to extend legacy models (ISAT), and provide a baseline for software solutions in the industry. Since that time, PODS has established itself as the industry standard.
The success of PODS is rooted in the unique nature of operators and vendors coming together to meet the storage, analysis, regulatory, and reporting needs of the industry. It is important to note that PODS is more than a data model: it’s a group of individuals coming together to discuss, evaluate, and establish the data needs for the industry. The work of the PODS organization extends well beyond how to model a pipeline in a database.
PODS exists predominately in two variations: PODS Relational and PODS Spatial. Both models share a structure and format that adheres to the PODS standards, but differ in how they’re implemented. PODS Relational leverages core relational database standards, and PODS Spatial provides a native implementation for Esri Geodatabases.
Important to note: even though PODS Relational is designed as a GIS-agnostic data model (i.e. it’s not a geodatabase), most every implementation I have worked with has vendor-developed implementation methods and toolsets that integrates with Esri’s ArcGIS platform.
ArcGIS Pipeline Data Model (APDM)
APDM is the Esri pipeline data model template for pipeline assets. As with all of the models provided by Esri, APDM is a method for operators to access a structured data model, free of charge, in full support of an Esri implementation.
The template nature of APDM differs from the standards designation of PODS by allowing any portion of the base template to be altered to meet implementation requirements. This flexibility is the single biggest deviation from the standards-driven approach of PODS. Another separation between APDM and PODS is that APDM focuses on the features that make up the pipeline network itself, and is not intended to be as encompassing as the PODS models.
With the release of the UPDM, APDM has ultimately been retired.
Utility and Pipeline Data Model (UPDM)
As mentioned, UPDM has essentially replaced APDM as the recommended Esri pipeline data model. This model provides an implementation foundation for gas and hazardous liquids industries. UPDM has been designed to work with or without the APR linear referencing component of the ArcGIS platform.
Most importantly, UPDM is the first model released that allows vertically-integrated utilities (gas distribution companies that operate regulated, high-pressure lines) to consolidate database schemas, and centralize data management to a single model.
I hope this post has helped demystify the world of pipeline data models, as there is a lot to consider and it can be difficult to understand.
Next week, I will dive into what you should consider when choosing the best pipeline data model for your operation, including the limitations of different models, how APR is addressing the limitations, and the questions you should be asking yourself.